Vitamin D Strategies in Chronic Kidney Disease Patients Need Personalization

New findings show that routine supplementation and testing may not benefit all CKD patients equally, highlighting the need for an individualized approach.

Topline:

Recent research presented at the National Kidney Foundation 2025 Meetings emphasizes that while vitamin D levels are often dysregulated in CKD patients, routine supplementation and testing offer uncertain benefits and should be personalized based on each patient's risk factors and clinical context.

Study Details:

At the NKF 2025 Spring Clinical Meetings, experts reviewed evidence about the role of vitamin D in chronic kidney disease (CKD). They confirmed that although most CKD patients have low 25-hydroxy vitamin D (25[OH]D) levels, the broader benefits of supplementation including mortality reduction or fracture prevention remain unproven. The discussion stressed that interventions must be carefully tailored rather than applied uniformly.

Methodology:

A comprehensive meta-analysis covering 128 studies and 11,270 patients was shared, comparing vitamin D treatments against placebos, other formulations, calcium, and cinacalcet across advanced CKD stages (III, IV, and V). The analysis examined outcomes like all-cause mortality, fractures, cardiovascular death, and biochemical markers like parathyroid hormone (PTH) and calcium levels.

Key Findings:

• Mortality and Fracture Outcomes:
  Vitamin D supplementation showed no clear mortality benefit (RR 1.04) and uncertain effects on fracture risk and cardiovascular death.

• Biochemical Changes:
  Vitamin D therapy did lower serum PTH and alkaline phosphatase but raised calcium levels, suggesting potential risks if not monitored carefully.

• Guideline Updates:
  Current KDIGO guidelines only suggest screening or supplementation in CKD patients based on individual risk profiles — they stop short of strong recommendations.

• Vitamin D and Prediabetes:
  A separate meta-analysis demonstrated that vitamin D supplementation (doses averaging 3500 IU/day) reduced progression from prediabetes to diabetes by 15%, providing strong justification for its use in this subgroup.

• Pill Burden Concerns:
  Experts raised concerns about adding another pill to already complex medication regimens, particularly for kidney transplant recipients, unless there is clear evidence of benefit.

Implications for Practice:

For patients and providers, these findings suggest a move away from routine vitamin D testing and supplementation in CKD unless specific clinical indications exist, such as co-existing prediabetes or severe hyperparathyroidism in advanced disease.

Healthcare providers should balance vitamin D’s limited proven benefits against the risks of increased calcium levels and pill burden.

Patients should engage in shared decision-making discussions with their nephrologists or endocrinologists about the risks, benefits, and relevance of vitamin D therapy in their specific cases.