Association between Androgenic Hair Patterns and Prostate Cancer Risk in South Indian Men: A Case-control Study from...

Prostate cancer (PCa) is one of the most common malignancies in men worldwide. Androgens influence both prostate growth and hair patterns. Androgenic alopecia (male-pattern baldness) and excessive male-pattern body hair (hypertrichosis) have been hypothesized as clinical markers of long-term androgen exposure. Previous Western studies have reported mixed results on whether early-onset or severe androgenic alopecia correlates with increased prostate cancer risk. Data in South Indian (Dravidian) populations is lacking.

To examine the association between androgenic hypertrichosis, androgenic alopecia, and prostate cancer in Dravidian men from the Cauvery Delta region of Tamil Nadu, India.

We conducted an age-stratified, population-based case-control study among men in the Cauvery Delta. The cases consisted of 117 men with pathologically confirmed adenocarcinoma of the prostate (diagnosed 2010-2015). Controls were 123 men with benign prostatic hyperplasia (BPH) from the same hospital registries, frequency-matched by age. Individuals with incomplete data or non-Dravidian (North Indian) ancestry were excluded. Trained investigators performed face-to-face interviews, directly observing and recording postpubertal body hair growth (indicative of androgenic hypertrichosis) and scalp hair loss (androgenic alopecia classified by the Norwood scale). Statistical analysis included multivariate discriminant analysis (Wilks' Lambda), one-way ANOVA for continuous variables, chi-square cross-tabulation, and computation of Cramer's V statistic to assess association strength. A two-tailed p-value of <0.05 was considered statistically significant.

The age distributions of cases and controls were comparable. The prevalence of androgenic hypertrichosis and alopecia did not differ significantly between prostate cancer cases and BPH controls. Cramer's V analysis showed that prostate cancer status accounted for only 1.1% of the variance in hypertrichosis (Cramer's V ≈ 0.011) and 1.5% of the variance in alopecia (Cramer's V ≈ 0.015).

In this case-control study of Dravidian men from Tamil Nadu, we observed no significant association between androgenic alopecia or hypertrichosis and prostate cancer. These findings contrast with data from Western cohorts, suggesting that interethnic variation in androgen receptor polymorphisms, follicular sensitivity, and environmental exposures may modulate prostate cancer risk differently. Further research is needed to elucidate how androgenic traits influence prostate carcinogenesis across different ethnic groups.