UCSF

Purpose

We examine the association between self-reported lower urinary tract symptoms and bowel habits in men in a large, cross-sectional, population based cohort study.

Materials and methods

The study included 3,077 men participating in the 2005-2006 or 2007-2008 cycles of the NHANES (National Health and Nutrition Examination Survey) who were 40 years old or older and without a history of prostate cancer. Men were considered to have lower urinary tract symptoms if they reported nocturia, urinary hesitancy and/or incomplete bladder emptying. Bowel habits were characterized by frequency of bowel movements per week and stool consistency based on the Bristol Stool Form Scale. Weighted associations between bowel habits and lower urinary tract symptoms were determined using univariate and multivariate techniques, adjusting for age, race, body mass index, diabetes, alcohol intake, activity level and smoking.

Results

The prevalence of lower urinary tract symptoms was 37%, with 4% reporting all 3 symptoms. Reporting 3 or fewer bowel movements per week was associated with nocturia (OR 1.67, 95% CI 1.21-2.30), incomplete bladder emptying (OR 2.14, 95% CI 1.06-4.31) and urinary hesitancy (OR 2.06, 95% CI 1.06-4.02). Reporting more than 10 bowel movements per week was associated with nocturia only (OR 1.42, 95% CI 1.01-1.55). Hard (OR 1.76, 95% CI 1.31-2.37) and loose (OR 1.25, 95% CI 1.01-1.55) stool consistency increased the odds of reporting nocturia.

Conclusions

Lower urinary tract symptoms in the adult male were independently associated with low stool frequency, hard stool type and loose stool type. These data suggest causality or a common pathophysiology of lower urinary tract symptoms and abnormalities of bowel habits.