Relationship Between Central Obesity, General Obesity, Overactive Bladder Syndrome and Urinary Incontinence Among Male and Female Patients Seeking Care for Their Lower Urinary Tract Symptoms

Abstract

Objectives: To describe the relationship between metabolic factors and lower urinary tract symptoms, overactive bladder syndrome (OAB) and urinary incontinence (UI).

Methods: Adult male and female patients who presented to a clinician from the symptoms of lower urinary tract dysfunction research network were recruited. Urinary symptoms (presence of OAB, any UI, stress UI (SUI), urgency UI (UUI), urgency, frequency, and nocturia) were assessed with the lower urinary tract symptoms tool. Metabolic factors assessed included central obesity (waist circumference, using the Adult Treatment Panel III, the International Diabetes Federation thresholds, and waist circumference as a continuous variable), general obesity (body mass index as dichotomous or continuous variables), diabetes mellitus, hypertension, and dyslipidemia. Multivariable logistic regression was used to test for associations.

Results: 920 participants were studied. In multivariable analyses, central obesity (per 10 cm larger waist) was associated with higher odds of UI in both sexes (odds ratio [OR] = 1.16, P = .008), SUI in females (OR = 1.27, P = .008), UUI in both sexes (OR = 1.24, P = .001), OAB in females (OR = 1.248, P = .003), as well as frequency and nocturia. General obesity (5-unit increase in body mass index) was associated with UI, UUI, urgency and frequency in both sexes, and with SUI and OAB in females. We did not find associations between central or general obesity and OAB in males. Dyslipidemia was associated with nocturia ≥2.

Conclusion: In patients, central and general obesity were key metabolic factors associated with UI in both males and females, and with OAB in females but not in males. The association between dyslipidemia and nocturia ≥2 needs further research.

Figure 1:. Scatterplots of body mass index (BMI) by waist circumference for males and females

with Pearson correlation coefficients (both p<0.001). Dashed lines show the ATP III criteria for central obesity (waist circumference ≥102 cm for males, ≥88 cm for females) and the general obesity criterion of BMI ≥30.

Figure 2:. Odds ratio of UUI in males for various measures of central obesity.

When waist circumference is included as a continuous variable, the log odds of UUI increases as waist circumference increases (solid line). When waist circumference is dichotomized, the averaged log odds is different enough that the difference is significant with the ATP III cutoffs (dashed line), but not with the IDF cutoffs (dashed-dotted line).