Our study investigated the constituent ratios of different subtypes of UI among women with overweight or obesity and the differences in their QoL and sexual function. We demonstrated variations in the constituent ratios of UI subtypes among patients with different degrees of UI. The severity of UI was greater in urgency UI and mixed UI than in stress UI, with varying subtype ratios observed at different severity levels: stress UI was greatest in mild cases (46.0%), and the mixed UI was greatest in moderate or severe cases (59.5%). Mixed UI had the most pronounced effect on QoL and sexual function. However, after controlling for UI severity, the mixed UI had a significantly greater impact on the UI-specific QoL, as evaluated by the UDI-6 and IIQ-7, whereas no differences were identified among the three groups regarding the general QoL, as evaluated by the EQ-5D-5L, or sexual function, as evaluated by the PISQ-12. These findings provide valuable insights into the characteristics of UI among women with overweight or obesity, highlighting the necessity of developing personalized treatment strategies for different subtypes of UI and offering scientific evidence for clinical treatment. Future research is needed to further investigate how lifestyle changes, medication, or surgical interventions can improve UI symptoms in women with overweight or obesity, thereby increasing their QoL.

Overweight and obesity have been established as important risk factors for UI, and current guidelines [4] advocate for multidisciplinary interventions encompassing nutrition and gynecological care for this high-risk population. However, current surveys still reveal a glaring lack of public knowledge regarding the heightened susceptibility to PFD conferred by obesity [19]. Previous research [6, 20] has demonstrated that the severity of UI symptoms increases with increased BMI and prolonged periods of obesity, underscoring the importance of lifelong weight management strategies. Currently, public awareness and physician engagement with this demographic information are still relatively inadequate, with a dearth of more personalized studies. A previous Brazilian study [12] included 221 individuals with obesity, 118 of whom (53.4%) experienced UI episodes: mixed UI, stress UI, and urgency UI were reported by 52.5% (62), 33.9% (40), and 13.6% (16) of the participants respectively, which aligns with our findings. However, when accounting for the severity of UI, there are stark discrepancies in the distribution of UI subtypes, with stress UI, urgency UI, and mixed UI accounting for 46%, 11%, and 43% respectively of the mild cases, and 25.2%, 15.2%, and 59.5% respectively of the moderate or severe cases.

Several previous studies have investigated the impact of UI subtypes on UI-specific QoL, and their findings align with ours, indicating that mixed UI may have the most detrimental effects [10, 21, 22]. However, in this study, the scores of patients on the UDI-6 and IIQ-7 were significantly lower than those reported in previous studies, which could be attributed to patient recruitment being conducted among those seeking medical weight loss rather than those seeking medical treatment owing to symptoms of UI. QoL can be assessed via both general and disease-specific tools. Disease-specific questionnaires effectively capture UI-related changes but may lack comprehensiveness. Women with overweight and obesity often face multifaceted QoL impacts, warranting a holistic assessment. Recent research has underscored the efficacy of the EQ-5D-5L in assessing QoL among individuals with UI, demonstrating robust construct validity, responsiveness, and reliability [23, 24]. However, current research lacks insights into the effects of different UI types on general QoL among women with overweight or obesity. In our study, the mixed UI had a significant negative impact on the general QoL, particularly in the anxiety/depression domain. However, after accounting for symptom severity, no significant differences emerged among the three groups regarding the general QoL.

The existing results examining the impact of different subtypes of UI on sexual function remain controversial [9, 10, 25]. The use of diverse assessment methods and variations in the definitions and classification of UI across different studies may contribute to these discordant findings. However, studies focused on the prevalence and impact of different UI subtypes among women with overweight or obesity are relatively rare. Our findings address this knowledge gap by revealing that mixed UI has the most significant negative impact on sexual function, encompassing both the behavioral/emotional and physical domains. However, the apparent greater impact of mixed UI on sexual function may be due to the greater severity of incontinence experienced by mixed UI patients. After controlling for UI severity, no significant differences were observed among the three groups. These findings could be attributed to several factors common to all forms of incontinence, such as the necessity of using a pad during intercourse, concerns about odor, and fears of urine leakage.

Our research holds clinical significance for several reasons. First, we employed all validated questionnaires, ensuring the reliability and applicability of the collected data. Second, we conducted a comprehensive evaluation of the various influences of UI subtypes on sexual function and QoL among women with overweight or obesity, providing a multidimensional assessment of the impact of different subtypes of UI on patients. However, it is crucial to acknowledge the limitations of our study. First, owing to its cross-sectional design, causality cannot be established, which limits our ability to determine the temporal relationship between UI subtypes and outcomes. Despite our efforts to account for potential confounding factors, the presence of some unmeasured confounders that could influence our results cannot be ruled out. Second, reliance on self-reported measures may lead to response bias and other errors, potentially compromising the validity of the results. Despite some measures taken to enhance data accuracy, the accuracy of the severity assessment of UI may still be compromised by recall bias or social desirability bias. Third, by limiting our sample to women actively seeking weight loss, the generalizability of the study’s findings, particularly those not seeking weight loss, is restricted. Last, although our center receives patients from a wide geographical area and recruitment was conducted consecutively, the inherent selection bias of a single-center study remains. Furthermore, despite the broad range in both patient age and BMI, the limited sample size prevented us from conducting further stratified analyses. In future investigations, to circumvent these limitations and derive more credible and rigorous conclusions, multicenter studies encompassing larger sample sizes and employing a prospective design will be essential.