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Risk factors for BPH


Clinical bottom line

High free PSA levels are associated with development of clinical BPH. High levels of physical activity and cigarette smoking appear to be protective.


JB Meigs et al. Risk factors for clinical benign prostatic hyperplasia in a community-based population of healthy aging men. Journal of Clinical Epidemiology 2001 54: 935-944.


This report is from the Massachusetts Male Ageing study, in 1,700 randomly selected men aged 40-70 in cities near Boston. A medical history and physical examination was made at baseline and blood sample collected. Follow up data was collected about eight years later.

The definition of clinical BPH was a positive response to questions about frequent urination or difficulty urinating and being told by a doctor that men had an enlarged or swollen prostate, or if medical chart review confirmed a transurethral prostatectomy for BPH.


Mean follow up was 8.8 years in 1,156 men, of whom 198 (19%) had a clinical diagnosis of BPH or surgery for BPH. The prevalence increased with age (Figure 1).

Figure 1: Prevalence of BPG with age at baseline

Age-adjusted risk factors were found to be high free-PSA concentrations (but not total PSA or free/total ratios), while protective effects appeared to be current cigarette smoking and high levels of physical activity (Table 1).

Table 1: Factors associated with developing BPH


Odds ratio (95%CI)

Free PSA 0.18 - 2.4 ng/mL

5.0 (2.9 to 8.6)

Current cigarette smoking

0.5 (0.3 to 0.8)

Physical activity > 850 kcal/day

0.5 (0.3 to 0.9)

Many other factors were examined and were found not to be associated with clinical BPH development.


This was a very thorough study. Very little is associated with developing BPH, and there appear to be few safe protective behaviours, other than high levels of physical activity.