The following is a summary of “Vitamin D status and treatment in ESKD; links to improved CKD-MBD laboratory parameters in a real-world setting,” published in the September 2024 issue of Nephrology by Holden et al.
Vitamin D deficiency is common among patients on hemodialysis, but there is no clear guidance on how to monitor or treat it.
Researchers conducted a prospective study exploring if increasing 25 (OH) D3 levels are linked to lower phosphate, parathyroid hormone (PTH), and alkaline phosphatase (ALP) levels.
They measured baseline 25(OH)D3 levels in all patients on in-center hemodialysis in June 2017. Lab results for phosphate and calcium were checked every 6 weeks, while 25(OH)D3, PTH, and ALP were checked every 12 weeks until February 2021. Starting in September 2018, a treatment of 50,000 IU vitamin D weekly until levels were adequate, then monthly, was introduced. The impact on calcium, phosphate, ALP, and PTH was analyzed using advanced regression models, linear spline effects, a log link function, and random effects.
The results showed that out of 697 patients, 15% had vitamin D deficiency (25[OH]D3 < 25 nmol/L), and 57% had insufficiency (between 25 and 74 nmol/L). With up to 7272 observations, increasing 25(OH)D3 led to a significant drop in PTH for levels between 25 and 75 nmol/L, continuing beyond 75 nmol/L without calcitriol. Phosphate levels also dropped significantly in the 25 to 75 nmol/L range and below 25 nmol/L in untreated patients. Calcium levels rose with an increasing 25(OH)D3. Only 0.2% of 25(OH)D3 levels exceeded 250 nmol/L, and 2.1% of calcium levels were high.
Investigators concluded that vitamin D treatment was safe and lowered PTH levels. However, it is unclear if the improvements in blood markers reduce overall health problems.
