Purpose: We define incidence rates and risk factors for acute urinary retention.
Materials and methods: In 1992, 41,276 United States male health professionals 45 to 83 years old self-reported baseline health data and American Urological Association symptom index scores. In 1995 a subset reported the year of any episode of acute urinary retention requiring catheterization. Of 8,418 respondents 6,100 without a history of prostate cancer, prostatectomy or acute urinary retention before 1992 provided data. Incidence rates from 1992 to 1995 were calculated and risk factors were assessed using logistic regression.
Results: During 15,851 person-years of followup 82 men reported an episode of acute urinary retention (sampling weighted incidence 4.5/1,000 person-years, 95% confidence intervals 3.1 to 6.2). Rates increased with age and baseline symptom severity. In men with symptom score 0 to 7 (none or mild lower urinary tract symptoms) the incidence of acute urinary retention increased from 0.4/1,000 person-years for those 45 to 49 years old to 7.9/1,000 person-years for those 70 to 83 years old. In men with symptom score 8 to 35 (moderate or severe lower urinary tract symptoms) rates increased from 3.3/1,000 person-years for those 45 to 49 years old to 11.3/1,000 person-years for those 70 to 83 years old. Men with a clinical diagnosis of benign prostatic hyperplasia and a symptom score 8 or greater had the highest rates (age adjusted incidence 13.7/1,000 person-years). All 7 lower urinary tract symptoms comprising the American Urological Association symptom index individually predicted acute urinary retention (age adjusted odds ratio 1.8 to 2.9 for symptoms occurring more than 25% of the time during the last month). The sensation of incomplete bladder emptying, having to void again after less than 2 hours and a weak urinary stream were the best independent symptom predictors. Use of medications with adrenergic or anticholinergic side effects also predicted acute urinary retention.
Conclusions: Acute urinary retention occurred relatively infrequently but older age, moderate or severe lower urinary tract symptoms, a diagnosis of benign prostatic hyperplasia and specific drug therapies significantly increased the risk of occurrence.