November 08, 2015

Just the Facts

This week’s JAMA included an article that describes prescription drug use in the US and compares current usage to the pattern twelve years earlier. The data for older patients is striking: in 1999-2000, 84% of people took at least one prescription drug; in 2011-2012, fully 90% of people took a prescription drug. More impressive, in the earlier period, 24% of older individuals took at least 5 prescription drugs (the cutoff for “polypharmacy”), while today it’s up to 39%. Is this good news or bad news?

One of my colleagues, who is an expert on drug policy, thinks that on the whole, more is better. Treatment of high blood pressure prevents strokes; treatment of high cholesterol prevents heart disease; antidepressants prevent suicide. My colleague worries about barriers to access for these life-saving and/or quality-of -ife-enhancing medications. The finding that more people are taking such drugs is encouraging: perhaps high cost or lack of primary care are not preventing patients from getting the medications they need. Other colleagues, who are geriatricians, think that on average, less is better. Polypharmacy is dangerous in frail, older individuals. The side-effects of medications, such as dizziness causing falls or low blood sugar causing fainting, may outweigh their benefits, especially when drugs are taken in combination.

The truth is that medication use in general and polypharmacy in particular are neither inherently good nor bad. Whether a given medication should or should not be prescribed depends very much on the circumstances. What the new report does is to describe patterns, allowing and encouraging us to zero in on classes of drugs whose use has changed markedly over time.

Particularly intriguing were the few drugs whose usage fell over the 12 year period studied. Almost all drugs were used more commonly. Among patients over age 65, only two categories of drugs fell to a statistically significant extent: sex hormones (almost exclusively estrogen replacement therapy) and anti-arrhythmics (drugs that were once widely used to try to control irregular heart rhythms). Now this is interesting because it’s very hard to get doctors to stop prescribing medication and to persuade patients that the medicine they've been taking for years, a drug they are convinced is beneficial, actually is useless or even harmful. But in the case of estrogen, new studies convincingly demonstrated that what was previously received wisdom—estrogen replacement in women prevented heart disease—was wrong. And in the case of anti-arrhythmics, drugs like quinidine and procainamide, which were once used to suppress abnormal ventricular rhythms, it turned out these medications were associated with an increased risk of sudden death. These drugs have virtually disappeared, replaced by other classes of drugs entirely. What these examples demonstrate is that when new data become available that are truly compelling, physician and patient behavior can change. It’s particularly helpful to be able to offer an alternative—a beta blocker instead of quinidine—rather than to subtract one drug without adding anything in its place.

The other takeaway message for me from this study is the tremendous importance of the National Center for Health Statistics. The data presented in the JAMA article come from NHANES, the National Health and Nutrition Examination Survey. This is a representative survey of a large number of Americans (37,959 in 2011-2012), conducted every few years, that gathers information about health and diet. It is, as the JAMA authors say, “a stratified, complex, probability-based survey” that over-samples older adults, low income individuals and certain racial and ethnic groups. Just what is the National Center for Health Statistics, the source of this treasure trove of data?

The National Center for Health Statistics was established in 1960. Since 1987, it has been part of the Centers for Disease Control (CDC). Its mission is to: “to provide statistical information that will guide actions and policies to improve the health of the American people.” In addition to conducting the NHANES surveys, it has three other data collection programs. There is the National Vital Statistics System, which gathers information about births and deaths and generates information about life expectancy. Then there is the National Health Interview Survey, which interviews Americans about their heath insurance coverage, health care resource utilization, and immunization status, along with other aspects of health. And there is the National Health Care Survey that studies the organizations that provide health care, such as hospitals, hospices, and nursing homes.

The studies carried out by the National Center for Health Statistics are invaluable. No private organization can be relied upon to carry them out systematically, regularly, and reliably. In a time when the federal government is under relentless attack, it’s worth drawing attention to some of its most remarkable—and unsung—achievements.

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