SALT LAKE CITY — Even among nursing home residents receiving substantial vitamin D supplements, half or more show deficiencies in the nutrient, according to two separate posters presented at the annual symposium of the American Medical Directors Association.
Researchers who conducted both studies suggested that nursing home residents should routinely receive two or more times the dose of the vitamin currently recommended for healthy elderly people.
“We were astounded to find how prevalent the deficiency in vitamin D was,” said Dr. Todd H. Goldberg, director of geriatrics at West Virginia University Health Sciences Center, Charleston, who conducted the study while he was the medical director of Paul's Run Retirement Community, Philadelphia.
Dr. Goldberg and his colleagues reviewed the charts of 105 residents of Paul's Run and the Allegheny Valley School, a home for adults with developmental disabilities, also in Philadelphia, and studied those that included data on concentrations of serum 25-hydroxyvitamin D (25[OH]D). All the residents had taken multivitamins and vitamin D-calcium supplements that yielded a total of 400–1,200 IU of the vitamin daily. Yet 38 of the 45 residents had 25(OH)D levels under 30 ng/mL, the target considered sufficient in most adults. Eleven had levels under 20 ng/mL, which Dr. Goldberg called “severely deficient.”
In the second study, Dr. William Zirker and Dr. Sri Yenupotula of the Crozer-Chester Medical Center in Upland, Pa., tested for 25(OH)D in 100 residents aged 65 years and older in the nursing home affiliated with the medical center. Although 84 residents were on the home's standard regimen of 800 IU of vitamin D with 1,200 mg of calcium daily, 35 (42%) had 25(OH)D levels under 30 ng/mL. Of the 16 residents not receiving the standard supplements, 12 were below the target level. “Our conclusion is that you can't just assume that you're going to achieve a target level by treating with the recommended [supplemental regimen],” said Dr. Zirker, chief of geriatric medicine at the medical center.
Dr. Zirker and Dr. Goldberg suggested different ways in which nursing homes could address vitamin D deficiency despite recommended supplementation.
Dr. Goldberg said that nursing home residents should be given extra over-the-counter vitamin D doses up to 2,000 IU per day routinely, whether or not their 25(OH)D levels are known. He pointed out that it can cost $100 for each test for the metabolite, whereas a hefty dose of vitamin D costs about 2 cents.
Conversely, Dr. Zirker advocated extensive blood testing. “We know that vitamin D deficiency is epidemic, particularly in nursing home residents,” he said. “All long-term care residents should have their 25(OH) D level checked after they have been on a standard [regimen] of 1,200 mg of calcium and 800 IU of vitamin D for at least 1–2 months,” he wrote. Residents with low 25(OH)D concentrations then should receive as much as 50,000 IU a week and then 50,000 IU a month.
In a separate presentation at the AMDA meeting, Dr. F. Michael Gloth III, director of outpatient services for geriatric medicine and gerontology at Johns Hopkins University, Baltimore, said that elderly people absorb 40% less vitamin D than young people do, and older skin produces less vitamin D when exposed to sunlight. The current Institute of Medicine-recommended daily intake of vitamin D (600 IU for people aged older than 70 years) “is nice, but it doesn't really apply to anyone you have in the nursing home,” said Dr. Gloth.
In long-term care, “one of the most beneficial interventions one can do is simply give people vitamin D supplements,” he concluded.