help button home button Endocrine Society JCEM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS

Journal of Clinical Endocrinology & Metabolism , doi:10.1210/jc.2005-0754
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Maser, R. E.
Right arrow Articles by Lenhard, M. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Maser, R. E.
Right arrow Articles by Lenhard, M. J.
Related Collections
Right arrow Cardiovascular Endocrinology
Right arrow Diabetes and Insulin
The Journal of Clinical Endocrinology & Metabolism Vol. 90, No. 10 5896-5903
Copyright © 2005 by The Endocrine Society


REVIEW

Cardiovascular Autonomic Neuropathy Due to Diabetes Mellitus: Clinical Manifestations, Consequences, and Treatment

Raelene E. Maser and M. James Lenhard

Department of Medical Technology (R.E.M.), University of Delaware, Newark, Delaware 19716; Diabetes and Metabolic Research Center (R.E.M., M.J.L.), Research Institute, Christiana Care Health Services, Newark, Delaware 19713; and Diabetes and Metabolic Diseases Center (M.J.L.), Christiana Care Health Services, Wilmington, Delaware 19801

Address all correspondence and requests for reprints to: Raelene E. Maser, Ph.D., Department of Medical Technology, 305F Willard Hall Education Building, University of Delaware, Newark, Delaware 19716. E-mail: rmaser{at}UDEL.EDU.


    Abstract
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
Context: The aim of this article was to review the importance of the clinical identification of persons with cardiovascular autonomic neuropathy (CAN) and discuss potential treatment interventions.

Evidence Acquisition: A MEDLINE search was conducted for articles published during the last 20 yr. In addition, subsequent references of retrieved articles were reviewed. Search strategies included using key terms such as CAN, heart rate variability, orthostatic hypotension, and diabetes mellitus.

Evidence Synthesis: CAN is a common form of diabetic autonomic neuropathy and causes abnormalities in heart rate control as well as central and peripheral vascular dynamics. The clinical manifestations of CAN include exercise intolerance, intraoperative cardiovascular lability, orthostatic hypotension, painless myocardial ischemia, and increased risk of mortality. CAN contributes to morbidity, mortality, and reduced quality of life for persons with diabetes. The American Diabetes Association has recently published a statement that provides guidelines for prevention, detection, and management of neuropathy, including CAN, for healthcare providers who care for patients with diabetes. Algorithms for the evaluation and treatment of the patient with CAN, even if the patient is asymptomatic, are provided in this review.

Conclusions: Once CAN is identified in a patient with diabetes, healthcare providers may consider altering the prescribed exercise regimen, increasing surveillance for cardiac ischemia, carefully reexamining the list of prescribed medications, and aggressively treating cardiovascular risk factors (e.g. hypertension) that may be associated with the development of CAN.


    Introduction
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
THE AUTONOMIC NERVOUS system modulates the electrical and contractile activity of the myocardium via the interplay of sympathetic and parasympathetic activity (1). An imbalance of autonomic control is implicated in the pathophysiology of arrhythmogenesis (1). Cardiovascular autonomic neuropathy (CAN), a common form of autonomic dysfunction found in patients with diabetes mellitus, causes abnormalities in heart rate control, as well as defects in central and peripheral vascular dynamics. Individuals with parasympathetic dysfunction have a high resting heart rate most likely because of vagal neuropathy that results in unopposed increased sympathetic outflow. Persons with a combined parasympathetic/sympathetic dysfunction have slower heart rates. With advanced nerve dysfunction, heart rate is fixed. Thus, it is apparent that the determination of heart rate itself is not a reliable diagnostic sign of CAN. Reduction in variability of heart rate is the earliest indicator of CAN. Clinical manifestations of CAN include exercise intolerance, intraoperative cardiovascular lability, orthostatic hypotension (OH), asymptomatic ischemia, painless myocardial infarction (MI), and increased risk of mortality (2). A recent publication by the American Diabetes Association highlighted the significance of diabetic neuropathy by issuing a statement for healthcare professionals that provides guidelines for prevention, detection, and management of neuropathy (3). In light of the statement by the American Diabetes Association, we discuss in this overview the clinical manifestations, consequences of, and therapeutic strategies for CAN in diabetic patients.


    Clinical Manifestations of Cardiovascular Autonomic Dysfunction
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
Exercise intolerance

In diabetic individuals with CAN, exercise tolerance is limited as a result of impaired parasympathetic/sympathetic responses that would normally enhance cardiac output and result in directing peripheral blood flow to skeletal muscles (4). Reduced ejection fraction, systolic dysfunction, and decreased diastolic filling, potentially as a result of CAN, also limit exercise tolerance (4). For diabetic persons likely to have CAN, it has been suggested that cardiac stress testing should be performed before beginning an exercise program (5). When discussing exercise instructions and goals with patients with CAN, healthcare providers need to emphasize that the use of heart rate is an inappropriate gauge of exercise intensity because maximal heart rate is depressed in persons with CAN (6). Recently it has been shown that percentage of heart rate reserve, an accurate predictor of percentage of VO2 reserve, can be used to prescribe and monitor exercise intensity in diabetic individuals with CAN (7). An alternate method for monitoring intensity of physical activity is the Rating of Perceived Exertion scale (7, 8). The Rating of Perceived Exertion scale, which uses the subjective feelings of intensity of the individual, can be used in clinical settings where maximal heart rate is not easily measured.

Intraoperative cardiovascular lability

There is a 2- to 3-fold increase in cardiovascular morbidity and mortality intraoperatively for patients with diabetes (9). Studies have demonstrated that the induction of anesthesia causes a greater degree of decline in heart rate and blood pressure in diabetic patients compared with nondiabetic individuals (10) and that hemodynamic stability, in the intraoperative period, depends on the severity of autonomic dysfunction (11). Patients with severe autonomic dysfunction have a high risk of blood pressure instability (11, 12), and intraoperative blood pressure support is needed more often in those with greater impairment (10). Intraoperative hypothermia (13), which may decrease drug metabolism and affect wound healing, and impaired hypoxic-induced ventilatory drive (14) have also been shown to be associated with the presence of CAN. Although one study failed to detect any association with abnormal hemodynamics during anesthesia in patients with diabetic CAN and coronary artery disease (15), noninvasive diagnostic methods assessing autonomic function allow identification of at-risk patients preoperatively and may better prepare the anesthesiologist for potential hemodynamic changes.

Orthostatic hypotension

A change from lying to standing normally results in activation of a baroreceptor-initiated, centrally mediated sympathetic reflex, resulting in an increase in peripheral vascular resistance and cardiac acceleration (9). OH is characterized by a defect in this reflex arc, resulting in signs and symptoms such as weakness, faintness, dizziness, visual impairment, and syncope. Although the absolute fall in blood pressure is arbitrary, OH is usually defined as a fall in blood pressure [i.e. >20–30 mm Hg for systolic or >10 mm Hg for diastolic (16, 17)] in response to postural change, from supine to standing.

Painless myocardial ischemia

Inability to detect ischemic pain can impair the recognition of myocardial ischemia or MI. The mechanisms of painless myocardial ischemia are, however, complex and not fully understood. Altered pain thresholds, subthreshold ischemia not sufficient to induce pain, and dysfunction of the afferent cardiac autonomic nerve fibers have all been suggested as possible mechanisms (18). A recent investigation that used positron emission tomography to measure regional cerebral blood flow as an index of regional neuronal activation has shown that impaired afferent signaling resulting from autonomic dysfunction is associated with failed signal transmission from the thalamus to the frontal cortex (19). Although evidence for a mechanistic link between diabetes and painless myocardial ischemia may not include autonomic dysfunction as some have suggested (20), it is hard to ignore the results of the Detection of Ischemia in Asymptomatic Diabetics study (21). In the Detection of Ischemia in Asymptomatic Diabetics study of 1123 patients with type 2 diabetes, cardiac autonomic dysfunction was a strong predictor of ischemia (21). A meta-analysis of 12 studies also demonstrated a consistent association between CAN and the presence of painless myocardial ischemia (2). The Mantel-Haenszel estimate for the pooled prevalence rate risk for silent myocardial ischemia was 1.96, with a 95% confidence interval of 1.53–2.51 (P < 0.001; n = 1468 total subjects) (2). Thus, patients with CAN warrant more careful attention. Cardiovascular autonomic function testing may be an important component in the risk assessment of diabetic patients with coronary artery disease (21).

Increased risk of mortality

Impaired autonomic control of heart rate is linked to increased risk of mortality. Reduced parasympathetic function or increased sympathetic activity may provide the propensity for lethal arrhythmias (22). In a recent meta-analysis of 15 studies among individuals with diabetes, CAN was found to be significantly associated with subsequent mortality when autonomic dysfunction was defined as the presence of two or more abnormalities of tests of heart rate variability (HRV) [i.e. pooled relative risk was 3.45 (95% confidence interval, 2.66–4.47; P < 0.001)] (23). The stronger association observed in studies defining CAN by the presence of two or more abnormalities may be due to more severe autonomic dysfunction in these individuals, specificity of assessment modalities, or a higher frequency of other comorbid complications.


    Measurement of Cardiovascular Autonomic Function
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
A complete discussion of various assessment modalities of cardiovascular autonomic function has been examined in an earlier technical review (2). Table 1Go provides a brief description of three assessment modalities (24, 25, 26, 27) that were recommended for longitudinal testing of cardiovascular autonomic function by a consensus conference (28).


View this table:
[in this window]
[in a new window]
 
TABLE 1. Modalities used for the assessment of cardiovascular autonomic function

 

    Treatment Interventions to Ameliorate Cardiovascular Autonomic Dysfunction via Pharmacological Agents
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
Interventions to ameliorate reduced HRV are being evaluated in clinical trials based on theories of the pathogenesis of diabetic neuropathy. Development of diabetic neuropathy is the result of a multifactorial process including metabolic insult to nerve fibers, neurovascular insufficiency, increased oxidative stress, reduction in neurotrophic growth factors, deficiency of essential fatty acids, formation of advanced glycosylation end products, and autoimmune damage (2). Various pharmacological agents that are directed at components of the pathogenic process are described below.

Glycemic control

The results of the Diabetes Control and Complications Trial showed that intensive treatment prevented the development of abnormal RR variation and slowed the deterioration of autonomic dysfunction over time (29). Eighteen years of follow-up of a group of type 1 diabetic individuals demonstrated that fair long-term glycemic control (i.e. glycosylated hemoglobin < 8.4%) was associated with preserved cardiovascular autonomic function, whereas lack of fair glycemic control was associated with dysfunction (30). For persons with type 2 diabetes, intensive insulin therapy showed a small tendency for improved autonomic function, whereas deterioration was noted in the conventionally treated group (31).

Antioxidants

During chronic hyperglycemia, the metabolism of glucose also results in the generation of free radicals. Although free radicals of superoxide and hydrogen peroxide are essential for normal cell function, excessive accumulation of free radicals is detrimental and has a direct neurotoxic effect (32). {alpha}-Lipoic acid, an antioxidant that reduces free radical formation, appears to slow progression of CAN (33, 34). For persons with type 2 diabetes, the improvement in CAN was seen after 4 months of treatment with an oral dosage of 800 mg/d (34). For persons with type 1 diabetes, the effect on autonomic function was seen after 10 d of 600 mg daily iv {alpha}-lipoic acid followed by 600 mg given orally for 50 d (33). It should be noted that many herbal manufacturers are promoting {alpha}-lipoic acid for use by patients with diabetes, but studies evaluating the effectiveness of these products have not been performed. Vitamin E has been shown to improve the ratio of cardiac sympathetic to parasympathetic tone for persons with type 2 diabetes (35). In light of a recent meta-analysis that found that 400 IU/d or more may increase all-cause mortality, high doses of vitamin E should be avoided (36).

Angiotensin converting enzyme (ACE) inhibitors

Microvascular insufficiency has also been proposed as a potential component in the pathogenesis of diabetic neuropathy. Results of animal studies have suggested that impaired ganglion blood flow in diabetes could be responsible for neurodegenerative changes in autonomic postganglionic cell bodies (37). In human diabetic neuropathy, impaired nerve blood flow has been demonstrated (38). Given that vascular dysfunction may be part of the pathogenesis of diabetic neuropathy, ameliorating this abnormality may positively benefit nerve function. ACE inhibitors promote vasodilation by preventing the generation of angiotensin II and by preventing the breakdown of bradykinin. Angiotensin II, in addition to its role as a vasoconstrictor, stimulates aldosterone release and promotes sympathetic outflow, thus ACE inhibitors may provide additional benefits as a result of the inhibition of angiotensin II. With regard to changes in HRV, the use of ACE inhibitors in patients with CAN has resulted in conflicting outcomes. Of the ACE inhibitors studied, 12 months of use of quinapril showed some degree of success in treating CAN (39), whereas no improvement of cardiovascular autonomic function was shown after 12 months of treatment with trandolapril (40). Conflicting results from various studies are disappointing, but it is important to remember that the effect of medications might not be homogeneous, even within the same class, and the beneficial response of an ACE inhibitor may depend on the degree of tissue penetration (41).

Angiotensin type 1 blockers

Angiotensin type 1 (AT1) receptor mediates all potentially deleterious effects of angiotensin II (42). AT1 antagonists block the AT1 receptor, thus blocking the harmful effects of angiotensin II. We conducted a 1-yr clinical trial in 44 diabetic individuals to determine the effect of losartan on HRV. We hypothesized that losartan would improve nerve function by increased nerve blood flow and inhibition of angiotensin II-induced facilitation of sympathetic neurotransmission. Although 50 mg of losartan appeared to slow the expected decline in RR variation, there was no significant improvement (43). Improved cardiovascular autonomic function was, however, shown in another study, in which 23 diabetic individuals were treated with 100 mg of losartan for 1 yr (44). Twelve weeks of treatment of losartan (50–100 mg/d) was also shown to reduce muscle sympathetic activity and improve cardiac baroreceptor sensitivity for 10 nondiabetic males with hypertension (45). In contrast, a 7-d trial in nondiabetic males treated with eprosartan was shown to lower HRV (46).

Aldosterone blockers

Aldosterone has been shown to affect the autonomic nervous system with sympathetic activation and parasympathetic inhibition (47) and impair the baroreflex response (48). Other dysfunctions associated with aldosterone include the blockage of myocardial uptake of norepinephrine in animal models (49) and decreased arterial and venous compliance, leading to vascular organ damage (50). Spironolactone, an aldosterone-receptor blocker, has been used to reduce the morbidity and mortality for patients with severe heart failure (47). Mechanisms thought to promote the beneficial effect of spironolactone include blocking the effect of aldosterone on the loss of potassium and magnesium and improved HRV (51, 52, 53). For example, acute administration of an aldosterone antagonist given iv has been shown to improve HRV and baroreflex sensitivity in healthy subjects, suggesting that aldosterone exerts a tonic inhibitory effect on cardiac vagal control (54). In disease-specific studies, the use of spironolactone improved HRV and survival for patients with congestive heart failure (51, 52, 53). In contrast, however, one study of individuals with type 2 diabetes administered spironolactone 50 mg/d for 1 month demonstrated a small but significant worsening in HRV (55). It is possible that the effects of spironolactone may be disease specific. To the best of our knowledge, eplerenone, a selective aldosterone blocker, has not been used to determine its effect on HRV in diabetic individuals.

Calcium-channel blockers

Calcium-channel blockers prevent the flow of calcium ions into cardiovascular cells by binding to the {alpha}1 subunit of the L-type voltage-gated calcium channel (56). The drug class is heterogenous, however, with reflex sympathetic activation after blood pressure reduction occurring more frequently after blockade with dihydropyridines than phenylalkylamines (56). In studies of hypertensive individuals, verapamil depressed sympathetic activity (56), and slow release diltiazem had favorable effects on autonomic function (57). Verapamil also decreased norepinephrine excretion in persons with stable angina pectoris (58) and improved parasympathetic function in nondiabetic patients after an acute MI (59). Although the mechanism by which verapamil influences HRV is not clear, it may be due to specific properties of the drug that have a suppressive effect on sympathetic outflow of catecholamines (59). Calcium-channel blockers may not, however, have a beneficial effect on HRV in persons with diabetes. For example, verapamil had no effect on HRV in diabetic subjects post-MI (59), whereas long-acting calcium antagonists enhanced, rather than reduced, sympathetic activity in patients with type 2 diabetes (60).

ß-Blockers

The use of ß-blockers in diabetic patients has been questioned because these agents may mask signs and symptoms of hypoglycemia and interfere with insulin release. Nonetheless, in the Cooperative Cardiovascular Project, post-MI diabetic patients treated with ß-blockers had a 36% reduction in mortality (61). In addition, ß-blockers were associated with a lower 1-yr mortality rate for elderly diabetic patients (62). The exact reason for the reduction in mortality may or may not be related to the effect on CAN. In the ß-blocker Heart Attack Trial, propranolol improved recovery of parasympathetic tone and decreased morning sympathetic predominance for post-MI patients (63). The addition of metoprolol to ramipril-treated type 1 diabetic patients with abnormal albuminuria was also shown to improve autonomic dysfunction (64).

Metformin

Free fatty acids (FFAs) interfere with glucose metabolism (65). Under normal circumstances, FFAs are the main fuel source for the heart (66). Recently, it has been shown that the combination of TNF-{alpha} and hyperglycemia stimulated lipolysis with a consequential increase in FFAs and induced insulin resistance (67). Decreased activation of the parasympathetic nervous system increases lipolysis, thus resulting in an increased concentration of FFAs in the plasma (66). An increase in FFAs has been shown to affect the cardiovascular system through activation of the sympathetic nervous system in healthy subjects (68), as well as in individuals with type 2 diabetes (69). Recently, it was demonstrated that overweight type 2 diabetic patients had metformin-related decreases in FFAs and insulin resistance that were associated with improved sympathovagal balance (70).


    Treatment Interventions to Ameliorate Cardiovascular Autonomic Dysfunction via Nonpharmacological Agents
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
It is well known that exercise plays an important role in the treatment of diabetes. The role of exercise in the improvement of cardiovascular autonomic function is not as clear. Numerous studies both in diabetic and nondiabetic populations have tried to determine whether HRV can be improved by exercise. For example, chronic endurance exercise training in sedentary adult males (71) and a single bout of submaximal endurance exercise in healthy males (72) were associated with increased HRV with a shift toward parasympathetic influence on cardiovascular function. Endurance training was also shown to improve vagal activity in nondiabetic patients who had a MI (73) and in insulin-requiring diabetic individuals with early CAN (74). Other studies showed no benefit or only minimal benefit for healthy men (75) and individuals with type 2 diabetes (76). The discordant findings are most likely due to differences in patient populations, lack of randomization, differences in length and type of exercise, and various measurements of autonomic function. Thus, more intervention studies are needed to determine the best exercise protocol that results in improved autonomic function for diabetic persons with CAN. In addition, it will be important to evaluate whether beneficial effects in autonomic function result in favorable effects on the clinical outcome (e.g. better exercise tolerance, decreased mortality) of these patients.

A suggested paradigm for treating diabetic individuals with autonomic dysfunction using both nonpharmacological and pharmacological agents is provided in Fig. 1Go. An assessment for microalbuminuria is included in the paradigm based on studies that have shown an association between CAN and microalbuminuria (77, 78, 79). Although a cause-effect relationship has not been proven, it is hypothesized that impairment of autonomic function is involved in the pathogenesis of diabetic nephropathy (77). The use of ACE inhibitors in the treatment of microalbuminuria is well established, and ACE inhibitors have been shown in some studies to improve HRV (39).



View larger version (21K):
[in this window]
[in a new window]
 
FIG. 1. Paradigm for treating diabetic individuals with cardiovascular autonomic dysfunction. Starting doses of all the medications mentioned in this review would have to be individualized for the patient considering the presence of other comorbid conditions. Patients would need to be followed closely with titration of medications determined according to individualized needs.

 

    Investigational Medications for Potential Use for Cardiovascular Autonomic Dysfunction
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
Aldose reductase inhibitors

Chronic hyperglycemia causes activation of the polyol pathway with the accumulation of sorbitol and fructose, resulting in various metabolic imbalances that lead to neuronal dysfunction (80). In the early 1980s, aldose reductase inhibitors (ARIs), which reduce activity in the polyol pathway, generated hope with regard to the potential treatment of diabetic neuropathy. Due to lack of safety and/or efficacy, however, several ARIs have been withdrawn from the market and currently no ARIs are available for use in the U.S. One ARI (i.e. epalrestat) has been marketed in Japan since 1995. Whereas two studies have shown improved measures of CAN with epalrestat administration (81, 82), another study showed no effect of epalrestat on cardiac sympathetic dysfunction (83). Recent results of a multicenter trial using zopolrestat indicated that measures of parasympathetic activity were not affected after 1 yr of treatment (84). Newer agents such as fidarestat and AS-3201 are being investigated in ongoing clinical trials assessing peripheral neuropathy.


    Treatment Interventions for OH
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
Treatment of OH comprises nonpharmacological and pharmacological measures. Nonpharmacological measures, such as increasing consumption of water (85) and wearing lower-extremity stockings, can be used to reduce symptoms (e.g. dizziness, dyspnea) (86). When treating OH due to autonomic dysfunction, pharmacological therapies must balance an increase in standing blood pressure against prevention of supine hypertension (86). In addition, OH can be aggravated by different forms of therapy [e.g. tricyclic antidepressant (amitriptyline)] used for the treatment of other complications (e.g. painful sensory neuropathy). Therefore, careful attention to other medications that may aggravate OH in these patients is necessary (87).

A suggested paradigm for treating diabetic individuals with OH is provided in Fig. 2Go. Medications that expand the plasma volume (fludrocortisone) or those that supplement {alpha} adrenergic activity (midodrine) are the main pharmacological agents used in the treatment of OH. The dose needed to achieve a clinical benefit may, however, be accompanied by side effects. Octreotide, an somatotropin release-inhibiting hormone analog, in combination with midodrine acts synergistically to reduce the hypotensive effects of the ingestion of food and standing in individuals with autonomic dysfunction (88). Treatment with erythropoietin of OH in anemic type 1 diabetic individuals with CAN has been shown to increase standing blood pressure (89). Recently, some novel approaches using other pharmacological agents have been investigated in nondiabetic individuals with OH. Enhancement of ganglionic transmission via the use of pyridostigmine (inhibitor of acetylcholinesterase) improved symptoms and orthostatic blood pressure with only modest effects in supine blood pressure for 15 patients with OH from numerous causes (90). Pyridostigmine has also been shown to improve HRV in healthy young adults (91). Fluoxetine, a selective serotonin reuptake inhibitor, improved hemodynamic parameters and symptoms of OH in patients with Parkinson’s disease (92). Animal studies indicate that enhanced baroreflex control of sympathetic nerve activity may be a possible mechanism for improved orthostatic tolerance as a result of treatment with fluoxetine (93). Clonidine, a centrally acting {alpha}-agonist hypotensive agent, has been successfully used in a few patients with symptomatic OH concomitant with supine hypertension (94). Investigation of agents for diabetic persons with OH that reduce supine hypertension is of particular importance.



View larger version (23K):
[in this window]
[in a new window]
 
FIG. 2. Paradigm for treating diabetic patients with OH. When assessing and treating OH in patients with diabetes, it is important to keep in mind that autonomic neuropathy is not the only cause of OH in patients with diabetes. Thus, it is important to evaluate the patient for causes that may not be related to diabetes.

 

    Summary and Conclusions
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 
A number of different therapeutic agents are emerging for the treatment of diabetic neuropathy. Not all investigational drugs (e.g. antiglycation agents, protein kinase C ß inhibitors, neurotrophic agents) have, however, been studied with regard to the effect on autonomic nerve-fiber function. Nonetheless, given the multifactorial process involved in the pathogenesis of diabetic neuropathy, it is likely that combination therapies directed at various components of the pathogenic pathway may be required. For persons with type 2 diabetes, intensive multifactorial treatment (e.g. targeting hyperglycemia, hypertension, dyslipidemia, and microalbuminuria) has been shown to reduce the risk of developing autonomic neuropathy (95). In addition, given the results of the European Diabetes Prospective Complications Study, which suggested that vascular factors (e.g. hypertension) may accelerate the adverse effects of hyperglycemia on nerve function, multifactorial intervention trials with diabetic neuropathy and CAN as primary outcomes appear warranted for individuals with diabetes (96, 97, 98). The concept of treating patients with asymptomatic CAN may not appeal to some physicians, particularly in light of the fact that there are no outcome data from clinical trials yet. However, given that the pathogenesis of neuropathy is affected by more than just glycemic control, we should endeavor to aggressively treat other risk factors, so as to prevent the onset and progression of complications, CAN being one of them.


    Acknowledgments
 
We thank Ripudaman S. Hundal, M.D., and Ronald P. Monsaert, M.D., for review of this manuscript.


    Footnotes
 
First Published Online July 12, 2005

Abbreviations: ACE, Angiotensin converting enzyme; ARI, aldose reductase inhibitor; AT1, angiotensin type 1; CAN, cardiovascular autonomic neuropathy; FFA, free fatty acid; HRV, heart rate variability; MI, myocardial infarction; OH, orthostatic hypotension.

Received April 6, 2005.

Accepted July 5, 2005.


    References
 Top
 Abstract
 Introduction
 Clinical Manifestations of...
 Measurement of Cardiovascular...
 Treatment Interventions to...
 Treatment Interventions to...
 Investigational Medications for...
 Treatment Interventions for OH
 Summary and Conclusions
 References
 

  1. Sztajzel J 2004 Heart rate variability: a noninvasive electrocardiographic method to measure the autonomic nervous system. Swiss Med Wkly 134:514–522[Medline]
  2. Vinik AI, Maser RE, Mitchell BD, Freeman R 2003 Diabetic autonomic neuropathy. Diabetes Care 26:1553–1579[Abstract/Free Full Text]
  3. Boulton AJM, Vinik AI, Arezzo JC, Bril V, Feldman EL, Freeman R, Malik RA, Maser RE, Sosenko JM, Ziegler D 2005 Diabetic neuropathies: a statement by the American Diabetes Association. Diabetes Care 28:956–962[Free Full Text]
  4. Vinik AI, Freeman R, Erbas T 2003 Diabetic autonomic neuropathy. Semin Neurol 23:365–372[CrossRef][Medline]
  5. Vinik AI, Erbas T 2002 Neuropathy. In: Ruderman N, Devlin JT, Schneider SH, Kriska A, eds. Handbook of exercise in diabetes. Alexandria, VA: American Diabetes Association; 463–496
  6. Albright AL 1998 Exercise precautions and recommendations for patients with autonomic neuropathy. Diabetes Spectrum 11:231–237
  7. Colberg SR, Swain DP, Vinik AI 2003 Use of heart rate reserve and rating of perceived exertion to prescribe exercise intensity in diabetic autonomic neuropathy. Diabetes Care 26:986–990[Abstract/Free Full Text]
  8. Albright A, Franz M, Hornsby G, Kriska A, Marrero D, Ullrich I, Verity LS 2000 American College of Sports Medicine position stand. Exercise and type 2 diabetes. Med Sci Sports Exerc 32:1345–1360[Medline]
  9. Ziegler D 1999 Cardiovascular autonomic neuropathy: clinical manifestations and measurement. Diabetes Reviews 7:342–357
  10. Burgos LG, Ebert TJ, Asiddao C, Turner LA, Pattison CZ, Wang-Cheng R, Kampine JP 1989 Increased intraoperative cardiovascular morbidity in diabetics with autonomic neuropathy. Anesthesiology 70:591–597[CrossRef][Medline]
  11. Knuttgen D, Buttner-Belz U, Gernot A, Doehn M 1990 Unstable blood pressure during anesthesia in diabetic patients with autonomic neuropathy. Anasth Intensivther Notfallmed 25:256–262[Medline]
  12. Latson TW, Ashmore TH, Reinhart DJ, Klein KW, Giesecke AH 1994 Autonomic reflex dysfunction in patients presenting for elective surgery is associated with hypotension after anesthesia induction. Anesthesiology 80:326–337[CrossRef][Medline]
  13. Kitamura A, Hoshino T, Kon T, Ogawa R 2000 Patients with diabetic neuropathy are at risk of a greater intraoperative reduction in core temperature. Anesthesiology 92:1311–1318[CrossRef][Medline]
  14. Sobotka PA, Liss HP, Vinik AI 1986 Impaired hypoxic ventilatory drive in diabetic patients with autonomic neuropathy. J Clin Endocrinol Metab 62:658–663[Abstract/Free Full Text]
  15. Keyl C, Lemberger P, Palitzsch KD, Hochmuth K, Liebold A, Hobbhahn J 1999 Cardiovascular autonomic dysfunction and hemodynamic response to anesthetic induction in patients with coronary artery disease and diabetes mellitus. Anesth Analg 88:985–991[Abstract/Free Full Text]
  16. Purewal TS, Watkins PJ 1995 Postural hypotension in diabetic autonomic neuropathy: a review. Diabet Med 12:192–200[Medline]
  17. Pfeifer MA 1990 Cardiovascular autonomic neuropathy: advances in testing help unlock its complexity. Diabetes Spectrum 3:45–48
  18. Shakespeare CF, Katritsis D, Crowther A, Cooper IC, Coltart JD, Webb-Peploe MM 1994 Differences in autonomic nerve function in patients with silent and symptomatic myocardial ischemia. Br Heart J 71:22–29[Abstract/Free Full Text]
  19. Rosen SD, Camici PG 2000 The brain-heart axis in the perception of cardiac pain: the elusive link between ischemia and pain. Ann Med 32:350–364[Medline]
  20. Airaksinen KEJ 2001 Silent coronary artery disease in diabetes—a feature of autonomic neuropathy or accelerated atherosclerosis? Diabetologia 44:259–266[CrossRef][Medline]
  21. Wackers FJ, Young LH, Inzucchi SE, Chyun DA, Davey JA, Barrett EJ, Taillefer R, Wittlin SD, Heller GV, Filipchuk N, Engel S, Ratner RE, Iskandrian AE, for the Detection of Ischemia in Asymptomatic Diabetics (DIAD) Investigators 2004 Detection of silent myocardial ischemia in asymptomatic diabetic subjects: the DIAD study. Diabetes Care 27:1954–1961[Abstract/Free Full Text]
  22. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology 1996 Heart rate variability: standards of measurement, physiological interpretation and clinical use. Circulation 93:1043–1065[Free Full Text]
  23. Maser RE, Mitchell BD, Vinik AI, Freeman R 2003 The association between cardiovascular autonomic neuropathy and mortality in individuals with diabetes: a meta-analysis. Diabetes Care 26:1895–1901[Abstract/Free Full Text]
  24. Schumer MP, Joyner SA, Pfeifer MA 1998 Cardiovascular autonomic neuropathy testing in patients with diabetes. Diabetes Spectrum 11:227–231
  25. Pfeifer MA, Schumer MP 1994 Cardiovascular autonomic neuropathy. Where have we been and where are we going? Diabetes Care 17:1545–1546[Medline]
  26. Ziegler D, Dannehl K, Muhlen H, Spuler M, Gries FA 1992 Prevalence of cardiovascular autonomic dysfunction assessed by spectral analysis, vector analysis, and standard tests of heart rate variation and blood pressure responses at various stages of diabetic neuropathy. Diabet Med 9:806–814[Medline]
  27. Genovely H, Pfeifer MA 1988 RR-variation: the autonomic test of choice in diabetes. Diabetes Metab Rev 4:255–271[Medline]
  28. Kahn R 1992 Proceedings of a consensus development conference on standardized measures in diabetic neuropathy. Autonomic nervous system testing. Diabetes Care 15:1095–1103[Medline]
  29. The Diabetes Control and Complications Trial Research Group 1998 The effect of intensive diabetes therapy on measures of autonomic nervous system function in the Diabetes Control and Complications Trial (DCCT). Diabetologia 41:416–423[CrossRef][Medline]
  30. Larsen JR, Sjoholm H, Berg TJ, Sandvik L, Brekke M, Hanssen KF, Dahl-Jorgensen K 2004 Eighteen years of fair glycemic control preserves cardiac autonomic function in type 1 diabetes. Diabetes Care 27:963–966[Abstract/Free Full Text]
  31. Ohkubo Y, Kishikawa H, Araki E, Miyata T, Isami S, Motoyoshi S, Kojima Y, Furuyoshi N, Shichiri M 1995 Intensive insulin therapy prevents the progression of diabetic microvascular complications in Japanese patients with non-insulin-dependent diabetes mellitus: a randomized prospective 6-year study. Diabetes Res Clin Pract 28:103–117[CrossRef][Medline]
  32. Bril V 2004 Filling the gap: emerging treatments for diabetic neuropathy. Adv Stud Med. 4:S662–S672
  33. Tankova T, Koev D, Dakovska L 2004 Alpha-lipoic acid in the treatment of autonomic diabetic neuropathy (controlled, randomized, open-label study). Rom J Intern Med 42:457–464[Medline]
  34. Ziegler D, Schatz H, Conrad F, Gries FA, Ulrich H, Reichel G 1997 Effects of treatment with the antioxidant alpha-lipoic acid on cardiac autonomic neuropathy in NIDDM patients. A 4-month randomized controlled multicenter trial (DEKAN Study). Diabetes Care 20:369–373[Abstract]
  35. Manzella D, Barbieri M, Ragno E, Paolisso G 2001 Chronic administration of pharmacologic doses of vitamin E improves the cardiac autonomic nervous system in patients with type 2 diabetes. Am J Clin Nutr 73:1052–1057[Abstract/Free Full Text]
  36. Miller ER, Pastor-Barriuso R, Dalal D, Riemersma RA, Appel LJ, Guallar E 2005 Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Ann Intern Med 142:37–46[Abstract/Free Full Text]
  37. Cameron NE, Cotter MA 2001 Diabetes causes an early reduction in autonomic ganglion blood flow in rats. J Diabetes Complications 15:198–202[CrossRef][Medline]
  38. Tesfaye S, Harris N, Jakubowski JJ, Mody C, Wilson RM, Rennie IG, Ward JD 1993 Impaired blood flow and arterio-venous shunting in human diabetic neuropathy: a novel technique of nerve photography and fluorescein angiography. Diabetologia 36:1266–1274[CrossRef][Medline]
  39. Athyros VG, Didangelos TP, Karamitsos DT, Papageorgiou AA, Boudoulas H, Kontopoulos AG 1998 Long-term effect of converting enzyme inhibition on circadian sympathetic and parasympathetic modulation in patients with diabetic autonomic neuropathy. Acta Cardiol 53:201–209[Medline]
  40. Malik RA, Williamson S, Abbott C, Carrington AL, Iqbal J, Schady W, Boulton AJ 1998 Effect of angiotensin-converting-enzyme (ACE) inhibitor trandolapril on human diabetic neuropathy: randomised double-blind controlled trial. Lancet 352:1978–1981[CrossRef][Medline]
  41. Malik RA 2000 Can diabetic neuropathy be prevented by angiotensin-converting enzyme inhibitors? Ann Med 32:1–5
  42. Timmermans PB, Chiu AT, Herblin WF, Wong PC, Smith RD 1992 Angiotensin II receptor subtypes. Am J Hypertens 5:406–410[Medline]
  43. Maser RE, Lenhard MJ 2003 Effect of treatment with losartan on cardiovascular autonomic and large sensory nerve fiber function in individuals with diabetes mellitus: a 1-year randomized, controlled trial. J Diabetes Complications 17:286–291[CrossRef][Medline]
  44. Didangelos TP, Arsos G, Karamitsos D, Athyros V, Georga S, Karatzas N 2002 Effect of quinapril or losartan or their combination on diabetic autonomic neuropathy and left ventricular function. Diabetologia 45(Suppl):84 (Abstract)
  45. Bechir M, Enseleit F, Chenevard R, Luscher TF, Noll G 2005 Effect of losartan on muscle sympathetic activity and baroreceptor function in systemic hypertension. Am J Cardiol 95:129–131[CrossRef][Medline]
  46. Heusser K, Vitkovsky J, Schmieder RE, Schobel HP 2003 AT1 antagonism by eprosartan lowers heart rate variability and baroreflex gain. Auton Neurosci 107:45–51[CrossRef][Medline]
  47. Pitt B, Zannad F, Remme WJ, Cody R, Castaigne A, Perez A, Palensky J, Wittes J, for the Randomized Aldactone Evaluation Study Investigators 1999 The effect of spironolactone on morbidity and mortality in patients with severe heart failure. N Engl J Med 341:709–717
  48. Yee KM, Struthers AD 1998 Aldosterone blunts the baroreflex response in man. Clin Sci 95:687–692[Medline]
  49. Barr CS, Lang CC, Hanson J, Arnott M, Kennedy N, Struthers AD 1995 Effects of adding spironolactone to an angiotensin-converting enzyme inhibitor in chronic congestive heart failure secondary to coronary artery disease. Am J Cardiol 76:1259–1265[CrossRef][Medline]
  50. Duprez D, De Buyzere M, Rietzschel ER, Clement DL 2000 Aldosterone and vascular damage. Cur Hypertens Rep 2:327–334[Medline]
  51. MacFadyen RJ, Barr CS, Struthers AD 1997 Aldosterone blockade reduces vascular collagen turnover, improves heart rate variability and reduces early morning rise in heart rate in heart failure patients. Cardiovasc Res 35:30–34[Abstract/Free Full Text]
  52. Korkmaz ME, Muderrisoglu H, Ulucam M, Ozin B 2000 Effects of spironolactone on heart rate variability and left ventricular systolic function in severe ischemic heart failure. Am J Cardiol 86:649–653[CrossRef][Medline]
  53. Yee KM, Pringle SD, Struthers AD 2001 Circadian variation in the effects of aldosterone blockade on heart rate variability and QT dispersion in congestive heart failure. J Am Coll Cardiol 37:1800–1807[Abstract/Free Full Text]
  54. Fletcher J, Buch AN, Routledge HC, Chowdhary S, Coote JH, Townend JN 2004 Acute aldosterone antagonism improves cardiac vagal control in humans. J Am Coll Cardiol 43:1270–1275[Abstract/Free Full Text]
  55. Davies JI, Band M, Morris A, Struthers AD 2004 Spironolactone impairs endothelial function and heart rate variability in patients with type 2 diabetes. Diabetologia 47:1687–1694[CrossRef][Medline]
  56. Kailasam MT, Parmer RJ, Cervenka JH, Wu RA, Ziegler MG, Kennedy BP, Adegbile IA, O’Connor DT 1995 Divergent effects on dihydropyridine and phenylalkylamine calcium channel antagonist classes on autonomic function in human hypertension. Hypertension 26:143–149[Abstract/Free Full Text]
  57. Kawano Y, Makino Y, Okuda N, Takishita S, Omae T 2000 Effects of diltiazem retard on ambulatory blood pressure and heart rate variability in patients with essential hypertension. Blood Press Monit 5:181–185[Medline]
  58. Forslund L, Bjorkander I, Ericson M, Held C, Kahan T, Rehnqvist N, Hjemdahl P 2002 Prognostic implications of autonomic function assessed by analyses of catecholamines and heart rate variability in stable angina pectoris. Heart 87:415–422[Abstract/Free Full Text]
  59. Pinar E, Garcia-Alberola A, Llamas C, Vicente T, Lopez-Candel J, Rojo JL, Fernandez R, Valdes M 1998 Effects of verapamil on indexes of heart rate variability after acute myocardial infarction. Am J Cardiol 81:1085–1089[CrossRef][Medline]
  60. Lopatin IuM, Kirakozov DA, Statsenko ME 2003 Heart rate variability in patients with hypertension and type 2 diabetes treated with long acting calcium antagonists. Kardiologiia 43:33–36
  61. Gottlieb SS, McCarter RJ, Vogel RA 1998 Effect of beta-blockade on mortality among high-risk and low-risk patients after myocardial infarction. N Engl J Med 339:489–497[Abstract/Free Full Text]
  62. Chen J, Marciniak TA, Radford MJ, Wang Y, Krumholz HM 1999 Beta-blocker therapy for secondary prevention of myocardial infarction in elderly diabetic patients. Results from the National Cooperative Cardiovascular Project. J Am Coll Cardiol 34:1388–1394[Abstract/Free Full Text]
  63. Lampert R, Ickovics JR, Viscoli CJ, Horwitz RI, Lee FA 2003 Effects of propranolol on recovery of heart rate variability following acute myocardial infarction and relation to outcome in the Beta-Blocker Heart Attack Trial. Am J Cardiol 91:137–142[CrossRef][Medline]
  64. Ebbehoj E, Poulsen PL, Hansen KW, Knudsen ST, Molgaard H, Mogensen CE 2002 Effects on heart rate variability of metoprolol supplementary to ongoing ACE-inhibitor treatment in type 1 diabetic patients with abnormal albuminuria. Diabetologia 45:965–975[CrossRef][Medline]
  65. de Kreutzenberg SV, Crepaldi C, Marchetto S, Calo L, Tiengo A, Del Prato S, Avogaro A 2000 Plasma free fatty acids and endothelium-dependent vasodilation: effect of chain-length and cyclooxygenase inhibition. J Clin Endocrinol Metab 85:793–798[Abstract/Free Full Text]
  66. Boden G, Hoeldtke RD 2003 Nerves, fat, and insulin resistance. N Engl J Med 349:1966–1967[Free Full Text]
  67. Green A, Rumberger JM, Stuart CA, Ruhoff MS 2004 Stimulation of lipolysis by tumor necrosis factor-alpha in 3T3–L1 adipocytes is glucose dependent: implications for long-term regulation of lipolysis. Diabetes 53:74–81[Abstract/Free Full Text]
  68. Paolisso G, Manzella D, Rizzo MR, Ragno E, Barbieri M, Varricchio G, Varricchio M 2000 Elevated plasma fatty acid concentrations stimulate the cardiac autonomic nervous system in healthy subjects. Am J Clin Nutr 72:723–730[Abstract/Free Full Text]
  69. Manzella D, Barbieri M, Rizzo MR, Ragno E, Passariello N, Gambardella A, Marfella R, Giugliano D, Paolisso G 2001 Role of free fatty acids on cardiac autonomic nervous system in noninsulin-dependent diabetic patients: effects of metabolic control. J Clin Endocrinol Metab 86:2769–2774[Abstract/Free Full Text]
  70. Manzella D, Grella R, Esposito K, Giugliano D, Barbagallo M, Paolisso G 2004 Blood pressure and cardiac autonomic nervous system in obese type 2 diabetic patients: effect of metformin administration. Am J Hypertens 17:223–227[CrossRef][Medline]
  71. Melanson EL, Freedson PS 2001 The effect of endurance training on resting heart rate variability in sedentary adult males. Eur J Appl Physiol 85:442–449[CrossRef][Medline]
  72. Pober DM, Braun B, Freedson PS 2004 Effects of a single bout of exercise on resting heart rate variability. Med Sci Sports Exerc 36:1140–1148[CrossRef][Medline]
  73. Malfatto G, Facchini M, Bragato R, Branzi G, Sala L, Leonetti G 1996 Short and long term effects of exercise training on the tonic autonomic modulation of heart rate variability after myocardial infarction. Eur Heart J 17:532–538[Abstract/Free Full Text]
  74. Howorka K, Pumprla J, Haber P, Koller-Strametz J, Mondrzyk J, Schabmann A 1997 Effects of physical training on heart rate variability in diabetic patients with various degrees of cardiovascular autonomic neuropathy. Cardiovasc Res 34:206–214[Abstract/Free Full Text]
  75. Loimaala A, Huikuri H, Oja P, Pasanen M, Vuori I 2000 Controlled 5-mo aerobic training improves heart rate but not heart rate variability or baroreflex sensitivity. J Appl Physiol 89:1825–1829[Abstract/Free Full Text]
  76. Loimaala A, Huikuri HV, Koobi T, Rinne M, Nenonen A, Vuori I 2003 Exercise training improves baroreflex sensitivity in type 2 diabetes. Diabetes 52:1837–1842[Abstract/Free Full Text]
  77. Moran A, Palmas W, Field L, Bhattarai J, Schwartz JE, Weinstock RS, Shea S 2004 Cardiovascular autonomic neuropathy is associated with microalbuminuria in older patients with type 2 diabetes. Diabetes Care 27:972–977[Abstract/Free Full Text]
  78. Smulders YM, Jager A, Gerritsen J, Dekker JM, Nijpels G, Heine RJ, Bouter LM, Stehouwer CDA 2000 Cardiovascular autonomic function is associated with (micro-) albuminuria in elderly Caucasian subjects with impaired glucose tolerance or type 2 diabetes: the Hoorn Study. Diabetes Care 23:1369–1374[Abstract/Free Full Text]
  79. Spallone V, Gambardella S, Maiello MR, Barini A, Frontoni S, Menzinger G 1994 Relationship between autonomic neuropathy, 24-h blood pressure profile, and nephropathy in normotensive IDDM patients. Diabetes Care 17:578–584[Abstract]
  80. Feldman EL, Vincent A 2004 The prevalence, impact, and multifactorial pathogenesis of diabetic peripheral neuropathy. Adv Stud Med. 4:S642–S649
  81. Okamoto H, Nomura M, Nakaya Y, Uehara K, Saito K, Kimura M, Chikamori K, Ito S 2003 Effects of epalrestat, an aldose reductase inhibitor, on diabetic neuropathy and gastroparesis. Intern Med 42:655–664[Medline]
  82. Ikeda T, Iwata K, Tanaka Y 1999 Long-term effect of epalrestat on cardiac autonomic neuropathy in subjects with non-insulin dependent diabetes mellitus. Diabetes Res Clin Pract 43:193–198[CrossRef][Medline]
  83. Komori H, Oi K, Takahashi D, Kunitou T, Moroi M 2004 The effect of epalrestat in cardiac sympathetic nerve dysfunction with type 2 diabetes. Diabetologia 47(Suppl 1):A368 (Abstract)
  84. Johnson BF, Nesto RW, Pfeifer MA, Slater WR, Vinik AI, Chyun DA, Law G, Wackers FJ, Young LH 2004 Cardiac abnormalities in diabetic patients with neuropathy: effects of aldose reductase inhibitor administration. Diabetes Care 27:448–454[Abstract/Free Full Text]
  85. Jordan J, Shannon JR, Black BK, Ali Y, Farley M, Costa F, Diedrich A, Robertson RM, Biaggioni I, Robertson D 2000 The pressor response to water drinking in humans: a sympathetic reflex? Circulation 101:504–509[Abstract/Free Full Text]
  86. Vinik AI 1999 Diabetic neuropathy: pathogenesis and therapy. Am J Med. 107(Suppl 2B):17S–26S
  87. Harati Y 1994 Diabetic peripheral neuropathy. In: Kominsky SJ, ed. Medical and surgical management of the diabetic foot. St. Louis, MO: Mosby; 83
  88. Hoeldtke RD, Horvath GG, Bryner KD, Hobbs GR 1998 Treatment of orthostatic hypotension with midodrine and octreotide. J Clin Endocrinol Metab 83:339–343[Abstract/Free Full Text]
  89. Winkler AS, Landau S, Watkins PJ 2001 Erythropoietin treatment of postural hypotension in anemic type 1 diabetic patients with autonomic neuropathy. Diabetes Care 24:1121–1123[Free Full Text]
  90. Singer W, Opfer-Gehrking TL, McPhee BR, Hilz MJ, Bharucha AE, Low PA 2003 Acetylcholinesterase inhibition: a novel approach in the treatment of neurogenic orthostatic hypotension. J Neurol Neurosurg Psychiatry 74:1294–1298[Abstract/Free Full Text]
  91. Nobrega AC, dos Reis AF, Moraes RS, Bastos BG, Ferlin EL, Ribeiro JP 2001 Enhancement of heart rate variability by cholinergic stimulation with pyridostigmine in healthy subjects. Clin Auton Res 11:11–17[CrossRef][Medline]
  92. Montastruc JL, Pelat M, Verwaerde P, Brefel-Courbon C, Tran MA, Blin O, Rascol O, Senard JM 1998 Fluoxetine in orthostatic hypotension of Parkinson’s disease: a clinical and experimental pilot study. Fundam Clin Pharmacol 12:398–402[Medline]
  93. Moffitt JA, Johnson AK 2004 Short-term fluoxetine treatment enhances baroreflex control of sympathetic nervous system activity after hindlimb unloading. Am J Physiol Regul Integr Comp Physiol. 286:R584–R590
  94. Brahmbhatt R, Baggaley P, Hockings B 2001 Normalization of blood pressure in a patient with severe orthostatic hypotension and supine hypertension using clonidine. Hypertension 37:e24
  95. Gaede P, Vedel P, Larsen N, Jensen GVH, Parving HH, Pedersen O 2003 Multifactorial intervention and cardiovascular disease in patients with type 2 diabetes. N Engl J Med 348:383–393[Abstract/Free Full Text]
  96. Witte DR, Tesfaye S, Chaturvedi N, Eaton SEM, Kempler P, Fuller JH, for the EURODIAB Prospective Complications Study Group 2005 Risk factors for cardiac autonomic neuropathy in type 1 diabetes mellitus. Diabetologia 48:164–171[CrossRef][Medline]
  97. Tesfaye S, Chaturvedi N, Eaton SEM, Ward JD, Manes C, Ionescu-Tirgoviste C, Witte DR, Fuller JH, for the EURODIAB Prospective Complications Study Group 2005 Vascular risk factors and diabetic neuropathy. N Engl J Med 352:341–350[Abstract/Free Full Text]
  98. Perkins BA, Bril V 2005 Early vascular risk factor modification in type 1 diabetes. N Engl J Med 352:408–409[Free Full Text]



This article has been cited by other articles:


Home page
Rheumatology (Oxford)Home page
Z. A. El-Sayed, G. A. Mostafa, G. S. Aly, G. S. El-Shahed, M. M. A. El-Aziz, and S. M. El-Emam
Cardiovascular autonomic function assessed by autonomic function tests and serum autonomic neuropeptides in Egyptian children and adolescents with rheumatic diseases
Rheumatology, July 1, 2009; 48(7): 843 - 848.
[Abstract] [Full Text] [PDF]


Home page
Diabetes CareHome page
S.-H. Ko, S.-A. Park, J.-H. Cho, K.-H. Song, K.-H. Yoon, B.-Y. Cha, H.-Y. Son, K.-D. Yoo, K.-W. Moon, Y.-M. Park, et al.
Progression of Cardiovascular Autonomic Dysfunction in Patients With Type 2 Diabetes: A 7-year follow-up study
Diabetes Care, September 1, 2008; 31(9): 1832 - 1836.
[Abstract] [Full Text] [PDF]


Home page
Diabetes CareHome page
J. L. Kitzmiller, J. M. Block, F. M. Brown, P. M. Catalano, D. L. Conway, D. R. Coustan, E. P. Gunderson, W. H. Herman, L. D. Hoffman, M. Inturrisi, et al.
Managing Preexisting Diabetes for Pregnancy: Summary of evidence and consensus recommendations for care
Diabetes Care, May 1, 2008; 31(5): 1060 - 1079.
[Full Text] [PDF]


Home page
Postgrad. Med. J.Home page
J M Pappachan, J Sebastian, B C Bino, K Jayaprakash, K Vijayakumar, P Sujathan, and L A Adinegara
Cardiac autonomic neuropathy in diabetes mellitus: prevalence, risk factors and utility of corrected QT interval in the ECG for its diagnosis
Postgrad. Med. J., April 1, 2008; 84(990): 205 - 210.
[Abstract] [Full Text] [PDF]


Home page
Exp PhysiolHome page
J. L. Ducla-Soares, M. Santos-Bento, S. Laranjo, A. Andrade, E. Ducla-Soares, J. P. Boto, L. Silva-Carvalho, and I. Rocha
Wavelet analysis of autonomic outflow of normal subjects on head-up tilt, cold pressor test, Valsalva manoeuvre and deep breathing
Exp Physiol, July 1, 2007; 92(4): 677 - 686.
[Abstract] [Full Text] [PDF]


This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Maser, R. E.
Right arrow Articles by Lenhard, M. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Maser, R. E.
Right arrow Articles by Lenhard, M. J.
Related Collections
Right arrow Cardiovascular Endocrinology
Right arrow Diabetes and Insulin


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals