Related Experiment Videos
Associations Between the Vitamin D Levels and Urinary Albumin-Creatinine Ratio in Adults With Hypertension
Youxue Zhang1, Xuexun Chen1, Xiangming Wang1
1Department of Nephrology, Affiliated Hospital of Shandong Second Medical University, Weifang, Shandong, China.
Insights
Low vitamin D levels are linked to higher urinary albumin-creatinine ratio (UACR) in hypertensive adults. Maintaining adequate vitamin D may help manage kidney risk associated with hypertension.
Area of Science:
- Nephrology
- Endocrinology
- Cardiovascular Medicine
Background:
- Hypertension is a significant risk factor for cardiovascular and kidney diseases.
- Elevated urinary albumin-creatinine ratio (UACR), even within normal ranges, indicates increased cardiovascular risk.
- The relationship between vitamin D levels and UACR in hypertensive individuals is not well understood.
Purpose of the Study:
- To investigate the association between serum vitamin D levels and UACR in adults with and without hypertension.
- To determine if vitamin D levels influence UACR differently in hypertensive versus nonhypertensive populations.
Main Methods:
- Cross-sectional study using National Health and Nutrition Examination Survey (NHANES) data (1999-2018).
- Included 37,554 US adults (19,802 with hypertension).
- Analyzed serum vitamin D levels and UACR using multivariable regression, restricted cubic splines, and subgroup analyses.
Main Results:
- An inverse association between vitamin D and UACR was more pronounced in hypertensive individuals (P interaction = 0.03).
- Vitamin D deficiency correlated with higher UACR compared to insufficiency (β = 0.23).
- A threshold effect was observed around 60 nmol/L, with lower levels showing a significant negative correlation with UACR (β = -0.14).
Conclusions:
- An L-shaped inverse association exists between serum vitamin D levels and UACR in US adults with hypertension.
- Lower vitamin D levels are associated with increased UACR in hypertensive individuals.
- Findings suggest a potential role for vitamin D in managing kidney health in 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 log2-transformed UACR. Restricted cubic splines, subgroup analyses, and sensitivity analyses were conducted to examine the nature and robustness of the association.
Results:
In patients with hypertension, the inverse association between vitamin D level and UACR was more pronounced than in nonhypertensive individuals (P for interaction = 0.03). Vitamin D deficiency was associated with 17.3% higher geometric mean UACR (β = 0.23) than insufficiency, whereas sufficient levels showed no significant difference (P = 0.51). A threshold effect was identified at approximately 60 nmol/L, with levels below this point showing a significant negative correlation (β = -0.14, equivalent to a 9.3% reduction in UACR, P < 0.001). These consistent findings were corroborated by subgroup and sensitivity analyses.
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.
Related Concept Videos
01:24Serum Studies: Renal Function Tests
01:28Drug Dosing in Renal Diseases: Estimation of Glomerular Filtration Rate Based on Serum Creatinine Concentration
01:25Drug Dosing in Renal Diseases: Measurement of Serum Creatinine Concentration and Clearance
01:30Acute Kidney Injury IV: Diagnostic Studies and Prevention
01:27Urinary Tract Calculi IV: Nutrition Therapy and Prevention
01:25Role of Vitamins in Maintaining Bone Health
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...