Catch-up Growth in Severe Juvenile Hypothyroidism: Treatment with a GnRH Analog

• DOI: 10.1515/jpem.2004.17.3.345
• Publication Date: 2011-04-15T11:36:07Z
• Authors: L. Teng; H. Bui; L. Bachrach; P. Lee; N. Gagné; C. Deal; D.M. Wilson
• Keywords: Adult; Male; 2. Zero hunger; Adolescent; Patient Selection; Puberty; Growth; Weight Gain; Body Height; Drug Administration Schedule; Body Mass Index; Gonadotropin-Releasing Hormone; Thyroxine; 03 medical and health sciences; 0302 clinical medicine; Hypothyroidism; Age Determination by Skeleton; Humans; Drug Therapy, Combination; Female; Child; Retrospective Studies

Anecdotal reports suggest that the addition of a gonadotropin releasing hormone (GnRH) analog (GnRHa) in addition to L-thyroxine (LT4) replacement may increase adult stature in children with severe longstanding hypothyroidism by prolonging the pubertal growth period. This retrospective chart review compares the height outcome and body mass index in 33 children (21 treated with LT4 alone and 12 treated with LT4 + GnRHa) with severe longstanding hypothyroidism and bone age delay. Seventeen controls and six GnRHa-treated patients were followed to adult height (BA >14 yr [F]/16 yr [M] and/or growth velocity < 2 cm/yr). At diagnosis, GnRHa-treated patients were 1) older and shorter for chronological age, and 2) more advanced in puberty and bone age. Despite these differences, at adult height, both groups had similar improvements in height Z scores, similar height deficits, and comparable adult heights. Changes in BMI Z score were similar for both groups. Our study suggests that the addition of GnRHa to LT4 may improve interval growth without imposing a risk of obesity in children with longstanding severe hypothyroidism.