SEATTLE — Vitamin D supplementation at twice the dose usually recommended for elderly individuals decreased falls in nursing home residents by 71%, Douglas P. Kiel, M.D., said at the annual meeting of the American Society for Bone and Mineral Research.
The usual dose of vitamin D recommended for bone health in elderly individuals is 400 IU a day. Vitamin D supplementation has been shown to decrease falls, but it is not certain if the usual dose is adequate for providing this benefit, said Dr. Kiel, director of medical research at the Hebrew Rehabilitation Center for Aged, Boston.
Dr. Kiel and his colleagues randomly assigned 125 elderly residents at a long-term care facility to one of four daily dosages of vitamin D, ranging up to 800 IU.
After 5 months, falls were reduced only among those who took the highest dose, Dr. Kiel noted in a poster presentation.
There were 9 falls among the 23 individuals who took 800 IU of vitamin D daily, compared with 31 falls among the 25 patients assigned placebo, 37 falls among 26 individuals who took 200 IU, 33 falls among 25 individuals who took 400 IU, and 41 falls among 25 individuals who took 600 IU.
The number of individuals who fell was also significantly reduced. Only 5 individuals taking 800-IU fell, compared with a range from 11 to 15 in the lower-dose and placebo groups.
Those figures translate into a three- to fourfold decrease in risk of falling for those who took the 800-IU dose of vitamin D, Dr. Kiel said.
Almost three-quarters of the individuals were already taking a multivitamin containing 400 IU of vitamin D, which could mean that the threshold dosage for preventing falls could be as high as 1,200 IU, Dr. Kiel noted.
The study subjects had a mean age of 89 years, and 72% were female.