July 30, 2003 -- A newer form of vitamin D cuts dialysis deaths, a major study shows.
There's a high death rate among people getting dialysis for kidney failure. It's nearly 20% per year. One problem is that these patients' parathyroid gland tends to kick into high gear, secreting dangerously high levels of hormone that can lead to hardening of the arteries, high blood pressure, and heart disease. Vitamin D counteracts this problem. But the doses of vitamin D needed are dangerous and can also increase deaths from heart disease.
A new form of vitamin D -- Zemplar, from Abbott Laboratories -- hit the market in 1998. Does it work better than normal vitamin D? Massachusetts General Hospital researcher Ravi Thadhani, MD, MPH, and colleagues compared some 29,000 dialysis patients on Zemplar to some 38,000 dialysis patients on regular vitamin D. They also looked at nearly 16,500 dialysis patients who switched from one to the other.
- After a year, the death rate among those who took Zemplar was 16% lower than among those who took regular vitamin D.
- The Zemplar benefit got bigger over time.
- Those who switched from regular vitamin D to Zemplar had a two-year survival rate of 73%.
- Those who switched from Zemplar to regular vitamin D had a two-year survival rate of 64%.
"This is the first evidence that a specific form of vitamin D can change the high rate of mortality among dialysis patients," Thadhani says in a news release. "If further research confirms our findings, this will be very important information for dialysis patients and their doctors."
There's more. Understanding exactly why the newer vitamin D helps patients may lead to new ways to help dialysis patients and kidney-transplant recipients.
The findings appear in the July 31 issue of TheNew England Journal of Medicine.