Ethnic differences in serum testosterone concentration among Malay, Chinese and Indian men: A cross-sectional study.

Objective: To investigate non-urological patients with multiple comorbidities for factors contributing towards differences in testosterone concentration in multiethnic Malaysian men.

Design: An observational study.

Patients: Sexually active men, ≥40 years, with no known urological problems, were recruited at the phlebotomy clinic at our centre.

Measurements: A brief history along with latest fasting lipid profile and plasma glucose levels were obtained. An Aging Male Symptoms questionnaire was administered; waist circumference (WC) and serum testosterone concentration were measured.

Statstical Analysis: Analysis of testosterone concentration between Malay, Indian and Chinese men was performed. Statistical tests such as analysis of variance, χ test, univariate and multivariable regression were performed. Any p < .05 was noted as statistically significant.

Results: Among the 604 participants analysed, mean testosterone concentration was significantly lower in Malays (15.1 ± 5.9 nmol/L) compared to the Chinese (17.0 ± 5.9 nmol/L) and Indian (16.1 ± 6.5 nmol/L) participants. The mean WC was also found to be higher among the Malays (96.1 ± 10.9 cm) compared to Chinese (92.6 ± 9.6 cm) and Indians (95.6 ± 9.9 cm). Testosterone concentration tended to be lower with higher age, but this was not statistically significant (p > .05). In the multivariable analysis only Malay ethnicity, WC ≥ 90 cm and low high-density lipoprotein (HDL) were associated with lower testosterone concentration.

Conclusion: In this study, Malaysian men of Malay origin had lower testosterone concentration compared with Indian and Chinese men. WC and low HDL were also associated with lower testosterone concentrations.