Associations between waist circumference and nocturia in adults: National health and nutrition examination survey 2005-2020

Background: The relationship between waist circumference and nocturia has not been previously studied. This study investigated the association between waist circumference and the occurrence of nocturia in adults. Methods: We analyzed data from the National Health and Nutrition Examination Survey covering 2005-2020, encompassing 6287 adults aged >= 20. Nocturia was defined as the need to urinate two or more times during the night. First, we compared baseline characteristics between the nocturia and non-nocturia groups. Subsequently, we used multivariate logistic regression analysis to investigate the relationship between waist circumference and nocturia prevalence. We also employed restricted cubic spline analysis to study the potential nonlinear correlation between waist circumference and the prevalence of nocturia. Recognizing the baseline data's heterogeneity based on nocturia prevalence, we conducted subgroup analyses according to age, sex, body mass index (BMI), and ethnicity. Results: Our findings indicated that females, individuals aged >= 50, citizens, Non-Hispanic Black, those with lower education levels (high school or less), higher BMIs, lower family income-to-poverty ratios, higher waist circumference, hypertension, and diabetes were more likely to experience nocturia. Compared with individuals in the lowest waist circumference quartile (Q1), those in the higher quartiles (Q4) exhibited an increased risk of nocturia in Model 1 (Q4, OR:2.00, 95% CI:1.64, 2.45, p < 0.0001). These results remained consistent after adjusting for covariates in models 2 and 3. A restricted cubic spline analysis suggested a linear association between waist circumference and nocturia (P for nonlinearity = 0.066). Subgroup analyses based on age, sex, BMI, and ethnicity revealed no significant differences in the interaction tests between waist circumference and nocturia (P for interaction = 0.437, 0.331, 0.121, and 0.889, respectively), indicating that these baseline characteristics did not influence the association. Conclusions: Our findings indicated an association between increased waist circumference and a higher prevalence of nocturia. Knowledge of this association reinforces the importance of lifestyle modifications in maintaining a healthy waist circumference and informs public health strategies to address other potential risk factors for nocturia.