Lower urinary tract symptoms and risk of prostate cancer: The HUNT 2 Cohort, Norway

Abstract

Screening for early prostate cancer is frequently employed in the routine management of men with lower urinary tract symptoms (LUTS), but the evidence-base linking LUTS with prostate cancer is limited. We assessed the association of LUTS with a subsequent prostate cancer diagnosis in a prospective cohort study based on 21,159 Norwegian men who completed baseline questionnaires, including the International Prostate Symptom Score (IPSS) questionnaire, between 1995 and 2007 as part of the second Nord-Trøndelag Health Study (HUNT 2). Men were followed-up for prostate cancer incidence and mortality from the date of clinical examination to end 2005. During a mean of 9 years follow-up, 518 incident prostate cancers were diagnosed and 74 men died from prostate cancer. Men with severe LUTS (IPSS 20-35) had a 2.26-fold (95% CI: 1.49-3.42) increased risk of prostate cancer compared to men reporting no symptoms. A positive association was observed for localized (hazard ratio, HR: 4.61; 2.23-9.54), but not advanced (HR: 0.51; 0.15-1.75), cancers (p for heterogeneity <0.001). There was no evidence that moderate/severe symptoms (IPSS 8-35) were associated with prostate cancer mortality (HR: 0.83; 0.42-1.64) vs. no symptoms. Amongst 518 men with prostate cancer, there was a 46% lower (10-68%) risk of death with moderate/severe symptoms vs. no symptoms. We conclude that LUTS are positively associated with localized, but not advanced or fatal, prostate cancer, suggesting that urinary symptoms are not caused by prostate cancer. Thus, screening for early cancers on the basis of LUTS may not be justified.