LACK OF BROMOCRIPTINE-INDUCED REDUCTION OF GROWTH PREDICTION IN TALL ADOLESCENTS

Abstract

It has been suggested that bromocriptine treatment of tall girls and boys reduces growth prediction by inhibiton of growth hormone secretion (J Clin Endocr Metab 58.1022-1026.1984). We have treated 15 girls and 5 boys (chron age 10.1-14.6 years. bone age 11.0-14.0 years) with bromocriptine (2×2.5 mg/day) over a period of 1.14 ± 0.31 years (0.6-1.75). Results (paired Wilcoxon rank test): The differences between the mean adult height prediction before and after bromocriptine were -0.8 ± 3.5 cm according to Bailey-Pinneau (p = 0.433) and +0.2 ± 2.5 cm according to Tanner Mark I (p = 0.586). The mean peak GH values after TRH i.v. were 53.0 ± 50.2 mU/l before, and 59.0 ± 50.2 mU/l during bromocriptine treatment (p = 0.314). The wide range of the GH results most probably reflects physiological variations in this age group. Our results are essentially negative. Moreover, the concept, that bromocriptine reduces GH secretion, seems doubtful: in 6 of our patients we have measured plasma GH after 2.5 mg of bromocriptine and found a significant increase within the first three hours. Our results do not support the data from the literature. We conclude, that bromocriptine is ineffective in reducing adult height of tall girls and boys. Supported by Swiss National Science Foundation grant 3.906.083.