Risk factors of pelvic floor disorders in the multiethnic cohort study

Background: Urinary incontinence (UI), fecal incontinence (FI), and pelvic organ prolapse (POP) are the three most prevalent pelvic floor disorders (PFD) in the world. In 2010, more than 28 million women in the US were diagnosed with at least one PFD, and the number is expected to increase to 43.8 million in 2050. [REF]The aims of this thesis are to investigate reproductive, lifestyle, and dietary risk factors for the three most common PFDs, UI, POP, and FI, across different racial/ethnic groups including White, Latino, African-American, Native Hawaiians, and Japanese Americans enrolled in the Multiethnic Cohort (MEC). ❧ Method: Data are available from Medicare and Medicaid Services claims (1999-2014) linked to individuals by Social Security number, sex and birthdate. We used these claims to identify women with a PFD, who defined cases for this analysis. All analyses were conducted for three main subtypes of PFD: UI, POP, and FI. For each subtype of PFD, descriptive analyses were performed and we presented frequency distributions of variables of interest and corresponding percentages. These subtype specific results were also presented for each racial/ethnic category. Univariate analyses were conducted by conditional logistic regression for each subtype and each race group adjusting for birth year, and number of months of Medicare coverage (+/- 12 months). Univariate analyses for each subtype were also adjusted for ethnicity. Multivariate conditional logistic regression models including smoking, reproductive factors, diet and other lifestyle factors were also conducted. ❧ Results: This analysis included 30,121 women, with 11,493 PFD patients and 18,628 controls, of these: 9,939 (86.48%) cases were diagnosed with UI, 2928 (25.48%) women had POP symptoms, and 667 (5.80%) women experienced FI. 16,034 controls were selected for patients with UI, 4,756 controls without any PFD were matched for cases with POP, and 1,072 controls were selected to compare with cases with FI. In the univariate analyses, number of children, progesterone use, estrogen use, total duration of estrogen use, surgical menopause, history of asthma or allergy, BMI and vitamin D intake were positively associated with risk of UI, but age at birth of first child, nulliparity, current smoking, coffee and regular coffee had an inverse association with risk of UI. Number of children, parity, progesterone use, estrogen use, duration of estrogen use, history of asthma or allergy, BMI, vitamin D intake and total fruits and juice was positively associated with risk of POP, but nulliparity, current smoking, total number of years smoked, average number of cigarettes per day, packs of cigarette per year, alcohol, coffee, regular coffee and calories were negatively associated with risk of POP. There were positive associations between progesterone use, estrogen use, history of asthma or allergy and risk of FI, and coffee, total vegetables with risk of FI. In the comprehensive models, estrogen use, previous progesterone use and BMI were still significantly positively associated with risk of UI, and nulliparity and coffee consumption were inversely associated with UI. Estrogen use and BMI were still positively associated with risk of POP, and nulliparity and packs of cigarette per year were inversely associated with risk of POP. Progesterone use was positively associated with risk of FI, and estrogen use, red meat (excluding processed red meat), total fruits and juice, coffee, and vigorous activity were inversely associated with risk of FI. ❧ Conclusion: Estrogen use, parity and BMI were positively associated with UI/POP both in the univariate analyses and multivariate models. Trend tests were statistically significant between these variables and risk of UI/POP in the univariate analyses. The positive association between estrogen use and risk of UI/POP was statistically significant among Hawaiians, and Japanese American. The protective effect of nulliparity on POP was identified for all racial/ethnic groups. Obesity was found to be a significant risk factor for UI and POP among Whites. Smoking was inversely associated with risk of POP among Hawaiians and Latinos, but the association only significantly existed among us-born Latinos. Also, negative association between alcohol and risk of POP was found among most of the racial/ethnic groups including Whites, African-American, Japanese American and foreign-born Latinos, but none of the associations were statistically significant. Coffee was identified to be inversely associated with all PFDs, especially among Hawaiians and Japanese. Vitamin D was positively associated with UI and POP, but none of the positive associations were statistically significant for all women combined. The positive association between vitamin D and risk of UI/POP was only significant among Latinos.