Endocrine Abstracts

Background

While almost all studies consistently show reduction of waist circumference as a result of testosterone therapy (TTh), effects on body weight are inconsistent and may depend on treatment duration, route of administration, and adherence.

Material and methods

After excluding men with primary hypogonadism, 476 men with functional, symptomatic hypogonadism were obese. 281 men received testosterone undecanoate injections 1000 mg/12 weeks following an initial 6-week interval (T-group), 195 men opted against TTh and served as controls (CTRL). Anthropometric measurements were performed at every visit for approximately 4.367 patient-years. 12-year data are reported. Changes over time between groups were compared and adjusted for age, weight, waist circumference, fasting glucose, blood pressure, lipids and quality of life to account for baseline differences between the two groups.

Results

Mean baseline age (years): 59.9 ± 5.5 (T-group), 62.9 ± 5.0 (CTRL) (P < 0.0001). Mean (median) follow-up: 9.4 ± 3.0 (11) years (T-group), 8.9 ± 3.0 (10) years (CTRL). Anthropometric parameters at 12 years, mean ± SE: Waist circumference (cm) decreased by 13.7 ± 0.3 (T-group) and increased by 8.1 ± 0.4 (CTRL), estimated adjusted difference between groups: –21.8 [95% CI: –22.9; –20.7] (P < 0.0001 for all). Weight (kg) decreased by 23.7 ± 0.4 (T-group) and increased by 7.3 ± 0.5 (CTRL), between-group difference: 31.0 [95% CI: –32.5; –29.6] (P < 0.0001 for all). Weight loss was 20.9 ± 0.3% (T-group), weight gain 7.8 ± 0.4% (CTRL), between-group difference: –28.7% [95% CI: –29.8; –27.5] (P < 0.0001 for all). BMI (kg/m²) decreased by 7.8 ± 0.2 (T-group) and increased by 2.5 ± 0.3 in CTRL, between-group difference: –10.2 [95% CI: –11.0; –9.5] (P < 0.0001 for all). Waist:height ratio decreased by 0.08 ± 0.00 (T-group) (P < 0.0001) and increased by 0.05 ± 0.00 (CTRL) (P = 0.05), between-group difference: –0.12 [95% CI: –0.13; –0.12] (P < 0.0001). The visceral adiposity index (VAI) decreased by 2.8 ± 0.1 (T-group) and increased by 3.8 ± 0.2 (CTRL), between-group difference: –6.6 [95% CI: –7.2; –6.1] (P < 0.0001). 25 patients (8.9%) died in the T-group and 77 (39.5%) in CTRL (P < 0.0001). Medication adherence to testosterone was 100% as all injections were administered in the medical office and documented.

Conclusion

In men with hypogonadism and obesity, long-term TTh improves anthropometric parameters which may be a contributing factor to the observed reduction in mortality.