March 28, 2016

Make No Bones About It

For some time, I’ve tried to find an up-to-date list of the medications most commonly prescribed to older people. Sounds like a simple question, but getting an answer has been surprisingly challenging. Most of the available data is ten years old and that’s a long time in an era when medications go off patent, new medications are introduced, and advertising campaigns affect medication use. Much of the information is for the population as a whole—but kids really are very different from octogenarians in their pill-taking. So I was pleased to find an article in JAMA Internal Medicine this week called “Changes in Prescription and Over-the Counter Medication and Dietary Supplement Use Among Older Adults in the United States, 2005 vs 2011.” This nationally representative sample of community dwelling older adults got its information from in-person interviews. It over-sampled certain populations to try to make sure its interviewees were truly representative. And the results are revealing.

The main finding is that fully 87.7 percent of adults over 65 (excluding those in institutions) took at least one prescription drug regularly in 2010-2011, up slightly 2005-2006. Moreover, 35.8 percent of the population take at least five prescription drugs a day (up significantly from 2005, when the rate was 30.6 percent. Lastly, there’s been a 50 percent increase in the number of people taking vitamins or supplements.

The Big Ten medications are pretty much what you would expect, though the actual percentages are a bit surprising. In first place is over-the-counter aspirin (40.2 percent); simvastatin, a cholesterol-lowering medication, is in second place (22.5 percent), and atorvastatin, another statin (formerly sold exclusively as Lipitor, before it lost patent protection) is number ten. The number three, four, six, and seven spots are taken by the anti-hypertensives, lisinopril (19.9 percent), hydrochlorothiazide (19.3 percent), metoprolol (14.9 percent), and amlodipine (13.4 percent) respectively, although it’s worth pointing out that these drugs can be used for other purposes besides lowering blood pressure—hydrochlorothiazide is a diuretic that may be used to treat heart failure, metoprolol is a beta-blocker often used to treat angina, and amlodipine is a calcium-channel blocker that can also be used in coronary artery disease. 

The remaining three drugs on the list are levothyroxine, a thyroid replacement medication, in fifth place, metformin, a drug used to treat diabetes, in eighth place, and omeprazole, a proton-pump inhibitor used for ulcers and acid reflux in the ninth spot. We are left wondering what all this means: are older people getting too many drugs? Not enough drugs? Are they getting the right medications?

Descriptive statistics cannot answer whether some patients are getting medicines they don’t need (though I’m pretty sure that’s the case) and others aren’t getting medicines from which they might benefit (probably also the case).  I think they do tell us something about the effectiveness of the strategies used to promote medications. When medications are categorized by type, statins are actually taken by just over 50 percent of older people (simvastatin and atorvastatin, drugs number 2 and 10 in the list of individual agents are not the only statins available) and anti-hypertensives by just over 65 percent of the elderly. What this tells me is that the combination of direct-to-consumer advertising, drug detailing to physicians, and  professional society guidelines--the methods used to promote statins and anti-hypertensives,at least when new drugs in each of these classes appeared on the scene--really works to change behavior. It doesn’t prove anything, but it’s awfully suggestive.

Also worth exploring is the dramatic increase in the percent of older people who take supplements. The authors of the study assert that this occurred although there is “no evidence of any clinical benefit.” I think this is a distortion. There may be little evidence of clinical benefit for some of the supplements, such as omega 3 fatty acids, but the story for vitamin D and calcium is both messier and more illuminating.

Over the years, Vitamin D has gone from being clearly necessary for strong bones, to very useful in preventing falls, to a dangerous poison, to a useless additive, and back again. Just what do we know as of 2016? We know that vitamin D is essential to human beings and we get it from sun exposure or from diet, although not many foods other than the ones such as milk to which we now add it naturally contain Vitamin D. Actually, that’s not quite accurate either, as what we get from the sun and from food is a pre-cursor of the active form of vitamin D that we need to make bones, and we rely on our kidneys and livers to perform the transformation. We also know from the National Health and Nutrition Examination Study that at least as of 2005-2006, 42 percent of adults had vitamin D levels below 20 ng/ml, which just about all authorities regard as too low. We also know that people who take megadose vitamin D as part of a fad diet, sometimes taking as much as 100 times the recommended daily dose, can get poisoned by such quantities.

The big question remains whether taking supplementary vitamin D—on the order of 800 units a day (not the tens of thousands of units taken by fad dieters)—prevents falls and fractures. Falls and fractures cost over $28 billion in older people, and that’s just the direct costs; it doesn’t include the pain and suffering and the loss of functioning and independence. The data on the efficacy of vitamin D are a mixed bag, with some studies showing strong evidence that it helps and a few failing to show any benefit at all. Putting all the conflicting evidence together, the American Geriatrics Society recommends, based on the preponderance of evidence, that all older adults, whether living in the community or in an institution, take vitamin D supplements of at least 1000 units together with calcium. Judging by the JAMA Internal Medicine article, we have a long way to go to reach this target: while 35 percent of older people do take a multivitamin (which includes 400 units of vitamin D), just under 16 percent take vitamin D alone.

The back story here is that vitamin D is cheap. No drug company is promoting vitamin D. In addition to being cheap, vitamin D has virtually no side effects (unless it is taken at hundreds of times the recommended dose). And it just might work. We should think about the ways that the consumption of cardiac medications have changed—and the ways that these changes have been achieved. We might learn something about how our system operates and how we can change the attitudes and behavior towards therapy that has a good chance of helping without breaking the bank.

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