Association Between Weight-Adjusted Waist Index and Chronic Diarrhea in US Adults: Insights from NHANES 2005-2010

OBJECTIVE We aimed to assess the association between the weight-adjusted waist circumference index (WWI) and chronic diarrhea in US adults. METHODS We selected individuals from the National Health and Nutrition Examination Survey (NHANES) database from 2005 to 2010 and used logistic regression analyses, subgroup analyses, and dose-response curves to assess the association between WWI and chronic diarrhea. RESULTS Of 11,322 participants included in this study (mean age, 47.22 ± 0.36 years; 5,731 [52.00%] female), 1,366 (12.07%) reported previous episodes of chronic diarrhea, whereas 9,956 (87.93%) did not. After adjusting for potential confounders, the WWI score was associated with chronic diarrhea (OR, 1.23; 95% CI, 1.05–1.44; P < 0.001). Compared to individuals in tertile 1 (Q1) of WWI scores (8.109 ≤ WWI score ≤ 10.45), those in tertile 4 (Q4; 11.572 < WWI score ≤ 15.704) had an adjusted OR for chronic diarrhea of 1.53 (95% CI, 1.14–2.05; P = 0.01; Table 2). The multivariable restricted cubic spline showed a nonlinear association between WWI and chronic diarrhea (P = 0.83). When the WWI score was ≥ 11.01, there was a correlation; however, no association was found in participants with a WWI score < 11.01 (P < 0.001). Subgroup analyses showed that WWI was associated with chronic diarrhea in men (OR, 1.548; 95% CI, 1.205–1.988) and individuals aged 40–60 years (OR, 1.370; 95% CI, 1.101–1.704), with a high educational level (OR, 1.297; 95% CI, 1.023–1.644), medium family income (OR, 1.385; 95% CI, 1.116–1.719), BMI > 30 kg/m² (OR, 1.266; 95% CI, 1.072–1.496), no chronic kidney disease (OR, 1.235; 95% CI, 1.030–1.480), hypertension (OR, 1.318; 95% CI, 1.069–1.626), diabetes mellitus (OR, 1.410; 95% CI, 1.090–1.823), hyperlipidemia (OR, 1.218; 95% CI, 1.027–1.444), no PHQ-9 (OR, 1.202; 95% CI, 1.022–1.415), and no coronary heart disease (OR, 1.239; 95% CI, 1.061–1.447). There was no significant interaction (P > 0.05). CONCLUSIONS The weight-adjusted waist circumference index is associated with chronic diarrhea in US adults.