Somatic and psychological effects of low-dose aromatase inhibition in men with obesity-related hypogonadotropic hypotestosteronemia.

S Loves, Internal Medicine, Rijnstate Hospital, Arnhem, 6800 TA, Netherlands.
European Journal of Endocrinology (Impact Factor: 3.69). 08/2013; DOI: 10.1530/EJE-13-0190
Source: PubMed

ABSTRACT Reduced testosterone levels are frequently observed in obese men. Increased aromatase activity may be an etiological factor.
To evaluate the clinical effects of aromatase inhibition in obesity-related hypogonadotropic hypotestosteronemia (OrHH).
Double-blind, placebo-controlled, 6-month trial in 42 obese men with a BMI > 35 kg/m2, and serum total testosterone levels < 10 nmol/L. All patients started on 1 tablet of 2.5 mg/week, with subsequent dose escalation every month until a serum total testosterone of 20 nmol/L was reached. Endpoints: psychological function, body composition, exercise capacity, and glucose, lipid and bone metabolism.
39 patients completed the study according to protocol. Letrozole decreased serum estradiol from 119.1 ± 10.1 to 59.2 ± 6.1 pmol/L (P < 0.001), increased serum LH from 3.3 ± 0.3 to 8.8 ± 0.9 U/L (P < 0.0001), and raised serum total testosterone from 8.6 ± 0.7 to 21.5 ± 1.3 nmol/L (P < 0.0001). Significant effects on the predefined endpoints were not observed.
Despite a marked rise in serum testosterone, low dose aromatase inhibition had no somatic or psychological effects in men with OrHH.

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