Weight and urinary incontinence: the missing links.

Excessive weight is an established and potent risk factor for urinary incontinence (UI) among women of all ages. Although few would doubt that weight plays a role in UI, there are still many uncertainties regarding weight as a risk factor. It must be clarified whether body mass index (BMI) is a better estimate than weight, waist circumference, or waist-hip ratio. It is not clear how the distribution of weight affects UI. Does being overweight due to heavy muscles, edema, or pregnancy lead to UI or only being overweight due to adiposity? It is unclear for how long a person's overweight must persist to lead to UI. We do not know whether weight is an appropriate measure of exposure or whether the association between weight and UI is confounded by socioeconomic status, diet, disease, or weight-related hormonal changes. This article summarizes knowledge gaps on the association between weight and UI.