The incidence of urinary incontinence across Asian, black, and white women in the United States.

Objective: We calculated incidence rates of urinary incontinence by incontinence frequency and type over 4 years in Asian, black, and white women in the United States.

Study Design: Prospective analyses included 76,724 participants aged 37-79 years in the Nurses' Health Study cohorts with no incontinence at baseline.

Results: The 4-year incidence of incontinence at least monthly was higher in white women (7.3/100 person-years) compared with Asian (5.7/100 person-years; P = .003) and black women (4.8/100 person-years; P < .001). The incidence of at least weekly stress incontinence was significantly lower in black compared with white women (0.1 vs 0.8 per 100 person-years; P < .001). The difference between black and white women in the incidence of any incontinence and stress incontinence remained significant after adjusting for known risk factors (P < .001 for both).

Conclusion: Urinary incontinence incidence differs by race. Studies to confirm these results and better understand underlying mechanisms are needed.