Hypergonadotropic hypogonadism in Nigerian men with type 2 diabetes mellitus

Background. Studies have reported a higher prevalence of hypogonadism in men with type 2 diabetes mellitus (T2DM) than non-diabetic men. The pattern of hypogonadism in men with T2DM using gonadotropin-releasing hormone (GnRH) stimulation test in Sub-Saharan Africa is unknown. Objective. This study was conducted to determine the prevalence and pattern of hypogonadism in Nigerian men with T2DM. Methods. A cross-sectional study involving 358 men with T2DM and 179 non-diabetic men as controls. Androgen Deficiency in the Ageing Male ( ADAM) questionnaire was administered. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) both at 0 hours and 4 hours after subcutaneous buserelin injection, fasting total testosterone (TT), fasting plasma glucose and glycated haemoglobin were measured. Ninety-nine men with T2DM selected by randomization using a computer underwent GnRH stimulation test, with subcutaneous injection of 100 micrograms of buserelin. Results. The mean TT of T2DM men was significantly lower compared to the controls (8.79 +/- 3.35 nmol/L vs 15.41 +/- 3.79 nmol/L, p < 0.001). The prevalence of hypogonadism in T2DM men was 80.4%, comprising 38.5% of severe hypogonadism and 41.9% mild hypogonadism. The mean LH and FSH levels were significantly higher in T2DM men than the controls (9.62 +/- 6.82 IU/L vs 8.24 +/- 5.91 IU/L, p = 0.022 and 8.50 +/- 8.17 IU/L vs 5.17 +/- 3.89 IU/L, p < 0.001 respectively). There was a statistically significant exaggerated response in mean (+/- SD) LH and FSH levels at 4 hours after buserelin injection compared to the 0-hour levels (58.58 +/- 40.72 IU/L vs 8.38 +/- 6.10 IU/L, p < 0.001 and 23.03 +/- 18.02 IU/L vs 8.41 +/- 7.45 IU/L, p < 0.001 respectively) in men with T2DM who had GnRH stimulation tests. Conclusion. This study shows that the prevalence of hypogonadism in men with T2DM is significantly higher than in non-diabetic men with mild hypogonadism accounting for most cases. Hypergonadotropic hypogonadism occurs more frequently in men with T2DM in Nigeria.