Vitamin D tablets: How much testing is necessary?Roger Hallett/The Globe and Mail
The much-hyped benefits of vitamin D have become so tantalizing that doctors in Ontario last year ordered nearly three-quarters of a million of the blood tests that determine a patient's level of the sunshine vitamin.
But the growing popularity has become a major issue. The provincial Ministry of Health is mulling over a proposal from its medical advisory committee to eliminate most of the discretion doctors have in asking for the $50 tests and have them paid by the province.
The committee says most of the tests are not medically necessary, prompting an outcry from practitioners who have found that many patients have dramatic health improvements after taking megadoses of vitamin D and who believe that the proposal is based on financial considerations rather than patient health.
But William Shragge, head of the committee recommending the change, says money was not a factor. "This has not been driven by costs. It's been driven by the evidence and the evidence we feel clearly supports our recommendation."
Health Minister Deb Matthews is expected to make a decision before the end of the year.
The proposal, if adopted, would probably return testing volumes back to the levels of 2004, before widespread interest by doctors and patients in vitamin D emerged and when only 30,000 of the tests were performed.
Critics of the proposal say vitamin D testing, rather than being discouraged, should be expanded to become a routine part of a medical checkup, just like readings for cholesterol or blood pressure. The savings from reduced vitamin D-linked illnesses will more than offset the costs, they believe.
"We can't tell by looking at someone what their blood level is. We need the tests to identify how low their levels are and to monitor their response to supplements," says Linda Rapson, a doctor specializing in treating chronic pain. She says many of her patients have extremely low amounts of the nutrient and have experienced quick health gains when they start taking vitamin D pills.
These patients would have to pay for the evaluation out of their pocket under the proposal, which would allow continuing Ontario Health Insurance Plan coverage only for a handful of conditions, including osteoporosis, rickets and kidney disease.
Therapy using vitamin D has emerged as a highly contentious area of medicine. It is widely accepted that small amounts of the nutrient are needed to prevent rickets, a debilitating bone disease, and to reduce the risk of osteoporosis among the elderly.
But a flurry of new research has linked having too little Vitamin D to a host of serious conditions, including cancer, influenza and autoimmune diseases such as multiple sclerosis. Much of this research is based on epidemiology - the same branch of medical science that fingered smoking as a hazard - that has found that those with the lowest blood levels of the vitamin are predisposed to these illnesses.
The mainstream medical community views epidemiology as a weak form of evidence and remains skeptical about the dramatic claims for vitamin D because they have not been confirmed by major clinical trials, the gold standard for evaluating drugs. "The [medical]literature is replete with megavitamin therapies for this, that and the other thing which, in fact, at the end of the day, have not borne out," Dr. Shragge observed.
But others are not so quick to dismiss vitamin D. A team of Canadian and U.S. researchers estimated this year that the Canadian health-care system could save $14-billion a year by preventing diseases epidemiology has linked to vitamin D insufficiency through a countrywide program of raising blood levels of the nutrient, according to a paper in the journal Molecular Nutrition and Food Research.
While the advisory committee's recommendation was not based financial concerns, the Health Ministry is worried about the cost.
The province estimates that if vitamin D testing continues to grow at current rates, the expense might top $150-million by 2012, up from $38-million last year.
The ministry said in an e-mail that it held discussions with the Ontario Association of Medical Laboratories, the body representing private testing companies, on "the appropriate utilization of laboratory testing and noted the exponential increases in vitamin D testing volumes."
After these discussions, it asked the advisory committee to evaluate the need for the test.
Members of the association, which did not respond to requests for comment, operate under a fixed annual budget from the province. When demand for one type of test unexpectedly surges, it cuts the industry's profit margins.
While the government mulls over its decision, some patients sing the praises of the raising their vitamin D levels.
Monique Richard, a Toronto woman who suffered from such severe muscle weakness that she could not climb stairs and could no longer walk any distance unaided, got her test results three weeks ago. She had such low readings that she was at risk of rickets. Previously, doctors had been unable to explain her condition.
She immediately began taking vitamin D supplements and within days was surprised to find her symptoms diminish. "It's going to sound [to you]like a story in the Bible," she says of her experience.