Associations Between the Vitamin D Levels and Urinary Albumin-Creatinine Ratio in Adults With Hypertension.

Rationale & Objective: Hypertension is a major risk factor for cardiovascular and kidney diseases. Although an elevated urinary albumin-creatinine ratio (UACR)-even within the normal range-predicts increased cardiovascular risk, and vitamin D level is associated with UACR in general populations, this relationship remains unclear in individuals with hypertension. Study Design: This study employed a cross-sectional design using data from the National Health and Nutrition Examination Survey (NHANES, 1999-2018). Setting & Participants: The study involved a cohort of 37,554 individuals, comprising 19,802 patients with hypertension and 17,752 nonhypertensive individuals from the United States, with a mean age of 46.7 ± 16.8 years. Exposure: Serum vitamin D levels. Outcome: UACR. Analytical Approach: Survey-weighted multivariable regression models were applied to assess the relationship between vitamin D level and log Results: In patients with hypertension, the inverse association between vitamin D level and UACR was more pronounced than in nonhypertensive individuals ( Limitations: The observational design precludes causal inferences, and residual confounding may persist despite adjustments. Generalizability may be limited, because data were derived from a single US cohort, and both vitamin D level and UACR relied on single measurements. Conclusions: There is an L-shaped inverse association between serum vitamin D levels and UACR among US adults with hypertension.