Impact of lower urinary tract symptoms on mortality: a 21-year follow-up among middle-aged and elderly Finnish men

Abstract

Background: The usefulness of lower urinary tract symptoms (LUTS) as mortality risk factors remains unclear. Repeated assessments are required to take into account symptom fluctuation and de novo symptom appearance. The study objective was to evaluate mortality in relation to three urinary storage symptoms—urgency, daytime frequency, and nocturia—in middle-aged and elderly men, considering also other time-varying factors during follow-up. Methods: A mail survey of a population-based cohort of men initially aged 50, 60, and 70 years was conducted in Finland in 1994, 1999, 2004, and 2009. The questionnaire included assessments of LUTS based on the Danish Prostatic Symptom Score and comorbidities. The men were followed up for mortality through the population registry through 2014. LUTS-related hazard ratios (HR) were analyzed with time-dependent Cox regression adjusted for the year of birth and comorbidities using variable values updated every 5 years. Sensitivity analyses were conducted using values of all variables fixed to the baseline assessment of 1994. Results: Of the 1332 eligible men with data on LUTS from each preceding survey, 514 (38.6%) died during the 21-year follow-up. In time-dependent analyses, daytime frequency, and nocturia were significantly associated with increased mortality: the adjusted HR was 1.42 (95% CI 1.11–1.83) for daytime frequency, 1.38 (1.07–1.79) for nocturia and 1.19 (0.94–1.50) for urgency. In sensitivity analyses with fixed baseline characteristics, only nocturia was suggestively associated with an increased risk of death: the adjusted HR was 1.09 (0.84–1.42) for daytime frequency, 1.41 (0.99–2.02) for nocturia and 0.94 (0.52–1.68) for urgency. Conclusions: Among aging men, LUTS are more accurate predictors of short-term than longer-term mortality risk. Repeated assessments are needed to detect clinically relevant and persistent symptoms, often associated with ill health. Accordingly, men with daytime frequency or nocturia exhibit a 1.4-fold risk of death and therefore, should be evaluated for underlying comorbidity.