Objective: To estimate the risk factors associated with onset of urinary incontinence in a rural community-dwelling elderly population.
Methods: The study area, village N in Akita Prefecture, is a rural community in which a baseline survey of TMIG-LISA (Tokyo Metropolitan Institute of Gerontology, Longitudinal and Interdisciplinary Study on Aging) was undertaken in 1996. Among the baseline subjects, 760 (314 males and 446 females) community-dwelling elderly people aged over 65, who did not suffer from urinary incontinence at entry of the survey were selected. This cohort has been followed for four years by multi-dimensional medical examination including interviews and physical performance tests, conducted on a yearly basis using similar methods to these for the baseline survey.
Results: After the 4-year follow-up, the incidence of urinary incontinence was 7.0% (22/314) in men and 12.3% (55/446) in women. The urinary incontinence group (UIG) had a significantly higher age and lower level of functional fitness at baseline for both sexes. In the UIG, the men but not the women had significantly lower serum levels of albumin and total cholesterol. By the logistic model, age (per 1-year increase: OR = 1.23, 95%CI: 1.11-1.38), and serum albumin (per 0.1 g/dl increase: OR = 0.70, 95%CI: 0.54-0.88) in men; and grip strength (per 1-kg increase: OR = 0.92, 95%CI: 0.86-0.98), social role (per 1-point decrease: OR = 1.81, 95%CI: 1.19-2.73), BMI (per 1-kg/m2 increase: OR = 1.10, 95%CI: 1.01-1.20) and smoking status (never smoker = 1.00, 3 = current smoker: OR = 7.53, 95%CI: 1.36-41.63) in women were independent variables significantly associated with onset of urinary incontinence.
Conclusions: Lifestyle and functional fitness are significantly associated with onset of urinary incontinence in this population. Our findings suggest that intervention programs are needed to improve pelvic floor muscle and to provide social support for the elderly.