An investigation of lower urinary tract symptoms and its potential associated factors in adult Chinese women with zero-inflated negative binomial regression model

Lower urinary tract symptoms (LUTS) have detrimental impact on health-related quality of life. This study has 2 aims: first to identify the optimum model for LUTS study and then to explore the potential associated factors of LUTS and bother LUTS with the optimum model among adult women in China. The survey was conducted in 6 regions of China between February and July 2006. A modified Chinese Bristol Female LUTS questionnaire was administered. The number of LUTS was the main outcome measure. The fitting goodness was compared to identify the optimum model with likelihood ratio test statistics. Zero-inflated negative binomial (ZINB) model was used to explore the potential associated factors of LUTS and bother LUTS. Of all 18,992 respondents, 55.5% of respondents reported one (any LUTS) or more LUTS (mixed LUTS) and 36.5% of respondents reported one or more bother LUTS. With the largest log likelihood and smallest AIC and BIC, ZINB model showed the best goodness of fit. In the ZINB model, we identified multiple associated factors for any LUTS and mixed LUTS; older age (β≥0.2), overweight [β = 0.059, 95%CI (0.016∼0.102)], obese [β = 0.143, 95%CI (0.087∼0.198)], postmenopausal status [β = 0.099, 95%CI (0.023∼0.175)], prolonged labor [β = 0.188, 95%CI (0.104∼0.272)], constipation [β = 0.309, 95%CI (0.262∼0.357)], coexisting pelvic organ prolapse (POP) [β = 0.348, 95%CI (0.224∼0.473)], diabetes (β = 0.178, 95%CI (0.100∼0.257), hypertension [β = 0.092, 95%CI (0.041∼0.143)], smoking (β = 0.192, 95%CI (0.127∼0.258) and alcohol consumption [β = 0.063, 95%CI (0.001∼0.126)] increased the odds of mixed LUTS. We identified multiple associated factors for bother LUTS and mixed LUTS; older age (β ≥ 0.1), prolonged labor [β = 0.153, 95%CI (0.031∼0.275)], constipation [β = 0.359, 95%CI (0.292∼0.426)] coexisting POP (β = 0.212, [95%CI (0.031∼0.393)], diabetes [β = 0.154, 95%CI (0.030∼0.278)], and smoking [β = 0.169, 95%CI (0.076∼0.262)] increased the odds of bother mixed LUTS. ZINB model was the optimum model to explore the potential associated factors of LUTS. Older age, coexisting POP and constipation were both closely related to any and bother LUTS, also the severity of LUTS. Compared to nulliparity, single or multiple deliveries and women who had perineal laceration had nothing to do with the severity of LUTS.