Synergistic interaction between hyperlipidemia and obesity as a risk factor for stress urinary incontinence in Americans

Abstract Urinary incontinence is a common disease among middle-aged and elderly women, which not only affects the physical and mental health of patients, but also brings a great medical burden to society. Obesity is a known risk factor for urinary incontinence and is the most common secondary cause of hyperlipidemia. Most obese patients also suffer from hyperlipidemia in the clinic. However, few studies have explored the role of hyperlipidemia in women with urinary incontinence. Using data from the 2005–2018 National Health and Nutrition Examination Survey (NHANES), we aimed to evaluated the independent associations of high body mass index and hyperlipidemia with urinary incontinence in Americans by conducting a weighted multivariate logistic regression model. Additive interactions were also assessed using the relative excess risk due to interaction (RERI), attributed proportion of interaction (AP) and synergy index (S). This study demonstrated that hyperlipidemia was associated with a higher risk of stress urinary incontinence among women with obesity (OR = 1.52, 95% CI = 1.03–2.25), and there was a significant synergistic effect of hyperlipidemia and obesity on stress urinary incontinence(adjusted RERI: 3.75, 95% CI 0.30–7.20; adjusted AP: 0.67, 95% CI 0.54–0.80; adjusted S: 5.49, 95% CI 4.15–7.27). Moreover, fasting serum triglyceride lipids were the most relevant blood lipid indicator for the risk of stress urinary incontinence, especially among obese women younger than 50 years old, which contributes to the development of more refined lipid control protocols for patients with urinary incontinence in different age groups.