Near Final Height in Males treated with Aromatase Inhibitors

Objective: Data on the impact of aromatase inhibitor (AI) therapy on final or near-final adult height (FNFH) in males with short stature is limited. This study investigated whether AI therapy improved FNFH in males with advanced or rapidly advancing bone age (ABA) and compromised predicted adult height. Methods: Data were collected through retrospective chart review. Descriptive statistics were used to characterize the study cohort. Fisher’s exact test and the Wilcoxon rank-sum test were used to compare outcomes. Results: Of 72 patients reviewed, 59 (82%) received anastrozole, 11 (15%) received letrozole, and 2 (2.8%) switched from anastrozole to letrozole. Median treatment duration was 25 [interquartile range (IQR): 18-32] months. Most common diagnoses included growth hormone (GH) deficiency (31%), early puberty and premature adrenarche (18%), idiopathic short stature (15%), overweight/obesity (14%). GH was used in 66%. The overall median gain in height (FNFH minus initial predicted height) was 1.2 cm (IQR: -1.9-4.2). Letrozole-treated patients showed a greater median height gain (4.2 cm, IQR: 0.6-13) compared to the anastrozole group (0.8 cm, IQR: -2.6-3.5; p=0.013) and reached a FNFH closer to mid-parental height (p=0.031). Longer duration of treatment, therapy at earlier puberty stages, and GH therapy were all significantly associated with greater gain in height (p values=0.005, 0.012, and 0.022, respectively). Conclusion: Our findings suggest that letrozole is associated with greater gain in height compared to anastrozole in males with ABA. Other factors associated with greater gains are treatment at earlier stages of puberty, longer duration of treatment and concurrent GH therapy.