A J-shaped link between body roundness index and albuminuria in U.S. adults: insights from NHANES 2005–2020

The relationship between Body Roundness Index (BRI) and albuminuria remains uncertain. This study examined the association between BRI, an innovative anthropometric metric, and albuminuria in a representative sample of adults. This study used data from the National Health and Nutrition Examination Survey (NHANES) spanning 2005 to 2020. BRI values were computed for 37,826 eligible participants. Urine albumin-to-creatinine ratio (ACR) values equal to or exceeding 30 mg/g were classified as albuminuria. Statistical analyses included weighted multivariable logistic regression models, two-piecewise linear regression models, smooth curve fittings, subgroup analyses, and interaction assessments. In the fully adjusted model, the odds ratio (OR) for the relationship between BRI and albuminuria was 1.18 (95% CI: 1.12–1.24). Furthermore, a non-linear J-shaped relationship was observed with a turning point at a BRI value of 3.08. Subgroup analyses revealed a stronger association in males (OR: 1.31, 95% CI: 1.24–1.39) than in females (OR: 1.11, 95% CI: 1.05–1.18). Our study identified a J-shaped relationship between BRI and albuminuria in adults.