This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kovatchev, B. P. Articles by Clarke, W. L. Search for Related Content PubMed PubMed Citation Articles by Kovatchev, B. P. Articles by Clarke, W. L.

Episodes of Severe Hypoglycemia in Type 1 Diabetes Are Preceded and Followed within 48 Hours by Measurable Disturbances in Blood Glucose¹

University of Virginia Health System and National Science Foundation Center for Biological Timing, University of Virginia (M.S.), Charlottesville, Virginia 22908

Address all correspondence and requests for reprints to: Dr. Boris P. Kovatchev, University of Virginia Health System, Box 800137, Charlottesville, Virginia 22908.

This study quantifies blood glucose (BG) disturbances occurring before and after episodes of severe hypoglycemia (SH). For 6–8 months, 85 individuals with type 1 diabetes and a history of SH (age, 44 ± 10 yr; 41 women and 44 men; duration of diabetes, 26 ± 11 yr; hemoglobin A_1c, 7.7 ± 1.1%) used Lifescan One Touch BG meters for self-monitoring three to five times daily and recorded the date and time of SH episodes in diaries. For each subject, the timing of SH episodes was located in the temporal stream of SMBG readings recorded by the meter, and characteristics, including the Low BG index (LBGI), were computed in 24-h increments. In the 24-h period before the SH episode LBGI rose (P < 0.001), average BG was lower (P = 0.001), and BG variance increased (P = 0.001). In the 24 h after SH, LBGI and BG variance remained elevated (P < 0.001), but average BG returned to baseline. These disturbances disappeared in 48 h. On the basis of LBGI we identified subjects at low, moderate, and high risk of SH, who reported, on the average, 1.7, 3.4, and 7.4 SH episodes (P < 0.005) during the study. In addition, we designed an algorithm that predicted 50% of all SH episodes that occurred in this subject group. We conclude that episodes of SH are preceded and followed by quantifiable BG disturbances, which could be used to devise warnings of imminent SH.

This article has been cited by other articles:

				L. R. Nielsen, U. Pedersen-Bjergaard, B. Thorsteinsson, M. Johansen, P. Damm, and E. R. Mathiesen Hypoglycemia in Pregnant Women With Type 1 Diabetes: Predictors and role of metabolic control Diabetes Care, January 1, 2008; 31(1): 9 - 14. [Abstract] [Full Text] [PDF]

				D. J. Cox, L. Gonder-Frederick, L. Ritterband, W. Clarke, and B. P. Kovatchev Prediction of Severe Hypoglycemia Diabetes Care, June 1, 2007; 30(6): 1370 - 1373. [Abstract] [Full Text] [PDF]

				A. S. Gangji, T. Cukierman, H. C. Gerstein, C. H. Goldsmith, and C. M. Clase A Systematic Review and Meta-Analysis of Hypoglycemia and Cardiovascular Events: A comparison of glyburide with other secretagogues and with insulin Diabetes Care, February 1, 2007; 30(2): 389 - 394. [Abstract] [Full Text] [PDF]

				American Diabetes Association Workgroup on Hypogly Defining and Reporting Hypoglycemia in Diabetes: A report from the American Diabetes Association Workgroup on Hypoglycemia Diabetes Care, May 1, 2005; 28(5): 1245 - 1249. [Full Text] [PDF]

				G. H. Murata, R. M. Hoffman, J. H. Shah, C. S. Wendel, and W. C. Duckworth A Probabilistic Model for Predicting Hypoglycemia in Type 2 Diabetes Mellitus: The Diabetes Outcomes in Veterans Study (DOVES) Arch Intern Med, July 12, 2004; 164(13): 1445 - 1450. [Abstract] [Full Text] [PDF]

				S. Salardi, S. Zucchini, R. Santoni, L. Ragni, S. Gualandi, A. Cicognani, and E. Cacciari The Glucose Area Under the Profiles Obtained With Continuous Glucose Monitoring System Relationships With HbAlc in Pediatric Type 1 Diabetic Patients Diabetes Care, October 1, 2002; 25(10): 1840 - 1844. [Abstract] [Full Text] [PDF]