Causal Relationship among Sexually Transmitted Infections, Frequency of Ejaculation and Benign Prostatic Hyperplasia: Emerging Facts or Myths?

Background: The prevalence of benign prostatic hyperplasia, BPH is increasing in our environment. Besides androgens and age could there be other risk factors? Aim: To investigate the roles of sexually transmitted infections, STI and frequency of ejaculation as risk factors for BPH. Methods: It was a prospective observational study carried out among predominantly Christian communities near Port Harcourt, a major cosmopolitan city in the oil rich Rivers State, in the Niger Delta region of Nigeria. Adult males above the age of 40 yrs old with no history of prostate cancer were invited to participate. History of marriage, duration of marriage, number of wives/sexual partners, frequency of sex or ejaculation and present or past history of STI were obtained through an interpreter administered questionnaire. Diagnosis of BPH was based on presence of lower urinary tract symptoms, ultrasound determination of increased prostate size and histopathology report to rule out prostate cancer. Linear logistic regression and odds ration were used to establish strength of association between BPH and frequency of ejaculation and history of various causative organisms for STI. Statistical significance was determined at p value of <0.05. Results: 754 respondents participated. Age ranged from 40 to 81 years. 92.6% were in a single relationship. 58.4% had 1 - 5 ejaculations per week. 8.2% has had syphilis, 32.6% has had gonorrhea and 1.1% has had candida infection. There was an observed positive relationship between history of gonorrhoea and increase in prostate size but the association was not statistically significant; syphilis showed no positive relationship with prostate enlargement; incidence of candidiasis was too low to establish causal relationship. Individuals who had sex once a week or less showed a higher prevalence of moderate/severe enlargement (42.3%) compared to those with more frequent sexual activity (35.7%) a relationship that approached significance (p = 0.071), with an odds ratio of 1.3 and narrow CI (0.9 to 1.7), suggesting a potential association that requires further investigation. Conclusion: There is an observed causal relationship between both previous history of gonorrhea infection and reduced frequency of ejaculation and prostate enlargement but these associations do not attain statistical significance and would need further studies.