Etiology of overactive bladder: a diet and lifestyle model for diabetes and obesity in older women.

Objective To evaluate a coherent, evidence-based hypothesis that specific modifiable lifestyle factors implicated in the development of diabetes and associated obesity are related to the onset of OAB. Methods: A hypothetical causative model for OAB involving modifiable lifestyle factors implicated in the development of diabetes and obesity was constructed, based on a systematic literature review. Secondary analysis of data was undertaken in a prospective cohort of women aged 40 and over, living in Leicestershire, UK. Subjects included 3,411 women free from OAB at baseline and 277 incident cases of OAB. Reported diet, lifestyle, morbid, and social factors were measured at baseline and incident cases at 1-year follow-up. Graphical chain modeling was used to estimate the associations between variables and identify likely pathways involved. Results: All hypothesized lifestyle factors (physical activity, high glycemic index, and high energy intake) plus diabetes and obesity were retained within the graph as potential contributors. However, low physical activity was the only direct risk factor linked prospectively to the onset of OAB (RR 2.47; 95% CI 1.82, 3.36), in addition to older age. Conclusions: Poor lifestyle factors causally linked to diabetes and obesity may contribute to the onset of OAB; low physical activity appears to be an important modifiable causal factor for OAB operating directly as well as indirectly via pathways involving obesity or diabetes. Further research is needed to demonstrate a causal link between lifestyle and OAB. Neurourol. Urodynam. 31: 487-495, 2012. (C) 2012 Wiley Periodicals, Inc.