ESPE Abstracts

Background: Aromatase inhibitors (AIs) have been suggested to slow down estrogen-dependent skeletal maturation in pubertal boys with short stature. In the literature, few studies evaluate the efficacy and safety of AIs in boys with growth hormone deficiency (GHD). Objective: To evaluate the auxologic effects and short-term laboratory profiles of combined AI and rhGH therapy in adolescent males with GHD.

Subjects and Methods: Male subjects between the ages of 10 and 16 with GHD from two different centers were included in the study. Patients were divided into two groups: (i) those who only used recombinant human growth hormone (rhGH) therapy for at least 1 year (Group I; G-I) and (ii) those who also used AI therapy (1 mg/day anastrozole or 2.5 mg/day letrozole) along with rhGH for at least 1 year (Group II; G-II).

Results: Forty-one patients (G-I, 46%; G-II, 54%) were included in the study. All of the subjects had isolated idiopathic GHD. At the beginning of the treatment, the chronological ages (CAs) of the patients in the G-I and G-II groups were 11.8 (10.9–13.7) and 12.8 (12.0–14.3) years, respectively. The ratios of bone age (BA)/CA for the two groups were 0.8 (0.8–0.9) and 1.0 (0.9–1.1), respectively (P<0.001). The daily dose of rhGH was similar in both groups (P=0.08). After the treatment, the median height SD scores of patients in the G-I group increased from -2.6 [(-3.4)-(-2.0)] to -1.8 [-2.1-(-1.3)], while subjects in the G-II group showed an increment from -1.7 [(-2.1)-(-1.1)] to -1.2 [(-1.6)-(-0.8)]. The post-therapy predicted adult height (PAH) significantly increased from baseline in all subjects in the G-I and G-II groups (P<0.001; P<0.001, respectively). There was no significant change in the ratio of BA/CA post-therapy in the G-I group (P=0.1), while there was a small but significant decrease in the G-II group (P<0.001). The growth velocities of the patients in the G-I and G-II groups were 9.1 (7.4–10.1) cm/year [1.5 (0.8–5.0) SD score] and 8.7 (7.5–9.9) cm/year [1.1 (0.3–3.1) SD score], respectively (P=0.6). While post-therapy serum testosterone concentrations were seen to increase in the G-II group, none of the patients exhibited hematocrit above 50 percent, and the fasting glucose concentrations were normal. Conclusions: AIs were observed to promote growth potential despite the advanced BA and puberty. AIs could be used as an additional therapy for pubertal boys with GHD.