Severe vitamin D deficiency is a risk factor for renal hyperfiltration

Area of Science:

• Nephrology
• Endocrinology
• Public Health

Background:

• Vitamin D deficiency is implicated in chronic kidney disease progression.
• Vitamin D supplementation shows promise for improving outcomes in diabetic and CKD patients.

Purpose of the Study:

• To investigate the association between renal hyperfiltration (RHF) and vitamin D status in a generally healthy adult population.
• To determine if low vitamin D levels are a risk factor for RHF in individuals with normal kidney function.

Main Methods:

• Cross-sectional analysis of 33,210 Korean adults from the NHANES (2008-2015) with normal renal function.
• Severe vitamin D deficiency defined as serum 25-hydroxyvitamin D <10 ng/mL.
• Renal hyperfiltration (RHF) defined as estimated GFR in the >95th percentile after covariate adjustment.

Main Results:

• Estimated glomerular filtration rate (eGFR) was negatively associated with serum 25-hydroxyvitamin D levels (β: -0.02, P < 0.001).
• The prevalence of RHF was significantly higher in individuals with severe vitamin D deficiency (5.8%) compared to those with sufficient levels (5.0%, P < 0.001).
• Severe vitamin D deficiency was a significant risk factor for RHF (OR: 2.41, P < 0.001).

Conclusions:

• Severe vitamin D deficiency is significantly associated with an increased prevalence of renal hyperfiltration in a healthy adult population.
• These findings highlight a potential link between vitamin D status and early kidney dysfunction, even in the absence of diagnosed kidney disease.