Natural history and effects on 2-year outcomes of urinary incontinence after stroke

We sought to describe the natural history of poststroke incontinence and estimate its effect on survival and 2-year outcomes in stroke survivors.

Two hundred thirty-five incident cases of stroke in 1995 were classified by continence status at 10 days after stroke. Age, sex, ethnicity, diabetes, hypertension, atrial fibrillation, premorbid disability, and Oxfordshire Community Stroke Project classification were recorded. Outcome data collected at 3 months and at 1 and 2 years included disability, case-fatality rates, and institutionalization rates. Disability was classified as severe, moderate, mild, or independent using the Barthel Index (without its "continence" component: 0-9, 10-14, 15-17, and 18, respectively) and Frenchay Activity Index (0-15, 16-30, and 31-45).

Of 235 cases, 95 were initially incontinent (group 1); 140 were continent (group 2). At the initial, 3-month, and 1- and 2-year assessments, incontinence was recorded in 95 patients (40%), 34 (19%), 23 (15%), and 12 (10%), respectively. In univariate analyses, the 2 groups were not different in terms of demographic factors and risk factors. Compared with group 2, group 1 patients were more likely to have atrial fibrillation (28% versus 16%; P:=0.02). Multivariate analyses showed that age >75 years (OR 15.9; CI 2.2 to 116.2), dysphagia (OR 4.03; CI 1.85 to 8.73), motor weakness (OR 5.41; CI 1.38 to 21.1) and visual field defects (OR 4.78; CI 1.78 to 12.9) were all significantly associated with incontinence. Incontinence was less common in lacunar infarctions (OR 0.12; CI 0.02 to 0.62). At 2 years, compared with group 2, group 1 had higher case-fatality rates (67% versus 20%; P:<0.001), higher institutionalization rates (39% versus 16%; P:=0.007), and greater disability (Barthel [0-9]: 39% versus 5%; P:<0.001; Frenchay [0-15]: 75% versus 37%; P:=0.001). Death or disability at 2 years was worse in subjects with initial incontinence(OR 4.43; CI 1.76 to 11.2).

Incontinence remains a prevalent condition 2 years after stroke. Initial incontinence was associated with age >75 years, dysphagia, visual field defect, and motor weakness. Poststroke incontinence adversely affected 2-year stroke survival, disability, and institutionalization rates.