Type 2 diabetes mellitus and risk of developing urinary incontinence.

OBJECTIVES

To evaluate the association between type 2 diabetes mellitus (DM) and development of urinary incontinence in women.

DESIGN

Prospective, observational study.

SETTING

The Nurses' Health Study cohort.

PARTICIPANTS

Eighty-one thousand eight hundred forty-five women who reported information on urinary function in 1996.

MEASUREMENTS

Self-reported, physician-diagnosed DM was ascertained using questionnaire from 1976 to 1996 and confirmed using standard criteria. Self-reported urinary incontinence, defined as leakage at least weekly, was ascertained in 1996 and 2000. Logistic regression models were used to calculate multivariate-adjusted relative risks (RRs) and 95% confidence intervals (CIs) for the relationship between DM (as of 1996) and prevalent and incident incontinence.

RESULTS

The risk of prevalent incontinence (multivariate RR=1.28, 95% CI=1.18-1.39) and incident incontinence (multivariate RR=1.21, 95% CI=1.02-1.43) was significantly greater in women with DM than women without. Using a validated severity index, risk of developing severe incontinence was even more substantial in women with DM than in those without (multivariate RR=1.40, 95% CI=1.15-1.71 for leakage enough to wet the underwear; RR=1.97, 95% CI=1.24-3.12 for leakage enough to wet the outer clothing). In addition, risk of incontinence increased with duration of DM (P-trend=.03 for prevalent incontinence; P=.001 for incident incontinence).

CONCLUSION

DM independently increases risk of urinary incontinence in women. Because risk of incontinence appeared associated with longer duration of DM, even delaying the onset of DM could have important public health implications.