This Article Full Text Full Text (PDF) Submit a related Letter to the Editor 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 Götherström, G. Articles by Svensson, J. Search for Related Content PubMed PubMed Citation Articles by Götherström, G. Articles by Svensson, J. Related Collections Neuroendocrinology and Pituitary Metabolism

Ten Years of Growth Hormone (GH) Replacement Normalizes Muscle Strength in GH-Deficient Adults

Research Center for Endocrinology and Metabolism (G.G., M.E., B.-Å.B., G.J., J.S.), Sahlgrenska University Hospital, and Research Group for Rehabilitation Medicine (K.S.-S.), Institute of Neuroscience and Physiology, Göteborg University, SE-413 45 Göteborg, Sweden

Address all correspondence and requests for reprints to: Galina Götherström, M.D., Research Centre for Endocrinology and Metabolism, Gröna Stråket 8, Sahlgrenska University Hospital, SE-413 45 Göteborg, Sweden. E-mail: galina.gotherstrom{at}gu.se.

Context: GH replacement for 1–5 yr improves, but does not fully normalize, muscle strength.

Objective, Design, and Patients: In this single-center, open-labeled, prospective study, the effects of 10 yr of GH replacement on muscle strength and neuromuscular function were followed in 109 consecutive adults (61 men; mean age 50.0 yr; range 22–74 yr) with adult-onset GH deficiency.

Results: The mean initial GH dose of 0.88 mg/d was gradually lowered to 0.47 mg/d. The mean IGF-I SD score increased from –1.54 at baseline to 1.12 at study end. GH replacement induced a sustained increase in lean mass and isometric knee flexor strength (60°). In most other measures of upper leg and handgrip strength, there were transient increases during the first half of the study (0–5 yr), whereas during the second half (5–10 yr), the absolute values of muscle strength decreased and returned to or even below the baseline values. However, after correction for age and gender using observed/predicted value ratios, there were sustained and, until 7 yr, even progressive increases in the measures of muscle strength. At study end, knee flexor strength had increased to 104–110% of predicted, knee extensor strength to 93–108%, and handgrip strength to 88–93%. Measurements of neuromuscular function showed reduced voluntary motor unit activation after 10 yr.

Conclusions: Ten years of GH replacement therapy increased muscle strength during the first half of the study and thereafter partly protected against the normal age-related decline in muscle strength and neuromuscular function, resulting in approximately normalized muscle strength after 10 yr.

This article has been cited by other articles:

				H. Filipsson and G. Johannsson GH replacement in adults: interactions with other pituitary hormone deficiencies and replacement therapies Eur. J. Endocrinol., November 1, 2009; 161(S1): S85 - S95. [Abstract] [Full Text] [PDF]

				O. Klefter and U. Feldt-Rasmussen Is increase in bone mineral content caused by increase in skeletal muscle mass/strength in adult patients with GH-treated GH deficiency? A systematic literature analysis Eur. J. Endocrinol., August 1, 2009; 161(2): 213 - 221. [Abstract] [Full Text] [PDF]