Frequently in preventive health we ask patients to take medications that will reduce the risk of a certain bad medical outcome years down the road: cholesterol-lowering agents that lower the risk of a heart attack, blood pressure-lowering agents that reduce the risk of kidney disease, glucose-lowering medications that reduce the risk of diabetes-related complications.

Sometimes these medications make patients feel better — for example, insulin in patients with symptomatic diabetes or a beta-blocker in someone with exertional angina — but more commonly patients get no tangible benefit from these medications on a day-to-day basis.

As doctors, we prescribe medications as a matter of course. If we deliberate, it is primarily in choosing which pill to prescribe. If the patient has hypertension, should we prescribe hydrochlorothiazide (HCTZ), an ACE-inhibitor, a calcium channel blocker, or a beta blocker? If a beta blocker, do we go with metoprolol or carvedilol or perhaps the newest beta blocker nebivolol? And what about the dose? There are sometimes good medical reasons to select one drug over another. There are dozens of clinical studies that test the use of different drugs in different patient populations and then there are evidence-based guidelines to help doctor make point-of-care decisions.

It turns out though that in practice despite the million dollar drug studies, the expert guidelines, and the deliberating, the most important thing we can do in prescribing a drug is to get our patients to actually take it. Adherence is a measure of how well a patient follows a treatment plan. Though the exact numbers vary by disease and treatment, adherence is on average 50 percent. That is, patients take their medications as prescribed about half the time.

As one might expect the harmful effects of low adherence are enormous. According to a recent report in JAMA, poor adherence accounts for an estimated 33 to 69 percent of medication-related hospital admissions with an estimated cost of $100 billion. More importantly, poor adherence is also a major contributor to preventable deaths and reduced quality of life. Adherence is also a huge public health opportunity. In one recent study, simply improving adherence to statins from 50 to 75 percent in patients at high risk for coronary heart disease averted twice as many cardiovascular deaths than would an equivalent increase in prescribing statins for those at lower risk. I would love to hear of any new drug or device that could match that kind of impact.

So why is adherence so low? And more importantly, what can we do about it?

Part of the problem is reimbursement. It’s easier for me to get a cardiac stress test covered for a patient than it is a pill box to help him or her organize and remember to take their blood pressure and cholesterol medications.

Part of the problem is human nature. We tend to place greater value on today than tomorrow. This practice of “discounting” actually makes economic sense and is the basis for a large segment of the financial industry. However, in general we tend to discount the future more than we should – a phenomenon called “hyperbolic discounting.” Because we place undue emphasis on today compared to tomorrow, we are even less likely to take a medication that does little for us today for the sake of future benefit.

Part of the problem is the health care system. Chronic diseases are not treated in doctor’s offices or even the hospital. They are treated at home; they are treated every day in the decisions people make over what to eat and what not to eat and in the little blue pill they choose to swallow every morning or not. But the health care system has little reach on the home; it is not designed around where chronic disease management and prevention actually happens.

Reimbursement is a Washington issue (though as citizens we can certainly make an impact). Human nature, while largely unchangeable, can be tricked into working for us. This largely has to do with patient education. By helping people “see” the daily benefits of the medications they are taking today, we can improve their health tomorrow.

For example, for hypertension, by encouraging people to track the change in their blood pressure daily or weekly, we can help them better relate the act of taking their medication each day to its long-term beneficial effects. Finally, we have the health care system. At my institution, I’m part of a study trying to link up a key part of a person’s daily life — his or her cell phone — to the health care system. Through automated text messages, we are helping patients with diabetes better remember to take their medications during the 8758 hours of the year they are not with us in clinic.

But there is certainly more all of us can do. For example, doctors do not regularly assess adherence. Imagine a clinic setting where adherence was the fifth vital sign right next to temperature, heart rate, blood pressure, and respiratory rate.

As doctors, we spend a lot of time hemming and hawing about which pill to give our patients. As researchers, we study new drugs in hopes that they will be a few percentage points better than the ones we have currently. One pill may be 5 percent better than next, but if the patient only takes it 50 percent of the time, does it really matter?

In our excitement over choosing between the red pill and the blue pill, we ought to spend more time just making sure our patients are actually taking the pills we give them.

Shantanu Nundy is an internal medicine physician and author of Stay Healthy At Every Age: What Your Doctor Wants You to Know.

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