Why Americans Don’t Take Their Medications, How Much It Costs, and What to do About It

Americans have a love-hate relationship with prescription drugs. They love that the drugs can lower their cholesterol or blood pressure or, if they’re diabetic, get their blood-sugar levels right. They hate paying for the medications and then have to remember every day to take them, sometimes several times through the day. So health policy analyst and physician Niteesh Choudhry, MD, PhD, has devoted his research to finding out why only about half of Americans take the drugs they’re supposed to and what can be done to fix that.

In November 2010, Dr. Choudhry had two significant papers on value-based insurance design, or VBID, published in the journal Health Affairs.(1,2) Dr. Choudhry, an Assistant Professor of Medicine at Harvard Medical School and an Associate Physician of the Division of Pharmacoepidemiology and Pharmacoeconomics at Brigham and Women’s Hospital in Boston, presented at the Leonard Davis Institute of Health Economics (LDI) 2010-2011 Research Series on November 12, 2010. The paper reported the experience of a large employer who applied VBID principles to drug co-payments.

Defining VBID
“VBID is part of a larger kind of thought amongst insurers and payers and even patients that we should pay for those health services that have value,” Dr. Choudhry said. It turns the prevailing principle of health insurance coverage—paying most for services that cost the most regardless of their clinical effectiveness—“on its head,” he said. “VBID says that, in an inverse way, we should pay the most for those services that are the most effective, or that patients should pay the least for those services,” he said.

Characteristic of Dr. Choudhry’s research is the paper he presented at LDIon Pitney Bowes’ new policy of either eliminating or lowering co-payments on cardiovascular drugs. Dr. Choudhry and his co-authors reported the policy was associated with an immediate 2.8% increase in adherence in statin therapy compared with controls. A 2007 study he co-authored suggested that covering combination therapy for heart attack patients would reduce the risk of another heart attack and death, and reduce per patient costs by $5,974 over three years.(3)

Putting a Price on the Problem
Cardiovascular disease draws Dr. Choudhry’s interest for several reasons. Heart attacks and strokes kill more people than any other cause, and it is “enormously expensive,” in his words: “If we add the costs of coronary artery disease, stroke, hypertension and congestive heart failure, we are talking well in excess of $300 billion a year in direct and indirect costs,” he said. Also, the efficacy of drug therapy has been well documented. “In cardiovascular disease, there’s a very clear, high-quality, large-scale data base of randomized trials that proves to us what we should do,” he said.

As diligent as physicians are in prescribing the appropriate drugs, getting patients to take them—what doctors call “adherence”—has been confounding. Additionally, these patients must typically commit themselves to lifetime therapy. Dr. Choudhry rattled off documented rates of adherence after heart attack: only 40% of patients prescribed cholesterol-lowering statins were taking them two years later; only about half were taking their anti-hypertension drugs.(4) The largest dropoff occurs three months after starting therapy, Dr. Choudhry said: up to 60% of people who have had a heart attack stop taking their heart medication.(5)

Dr. Choudhry cited research from pharmacy benefits manager Medco Health Solutions that showed that for every 10% drop in adherence, overall health care costs increase 10%.(6) In a public health context, non-adherence accounts for 125,000 deaths a year, 11% of all hospitalizations and $100 billion to $200 billion in health expenditures.(6) “To put that in the context of other public health problems, it ranks right up there with obesity and smoking,” he said.

How to Fix It
Medicine can take two approaches to correcting that health problem: improve treatments and technologies, which can be prohibitively expensive; or get patients to take their medications—“just doing what we already know how to do,” he said.
Dr. Choudhry and his colleagues have concentrated on flaws in the drug delivery system that may keep people from taking their needed drugs, focusing on treatment regimens and dosing and cost.

“If you give someone a medication that he or she needs to take four times and instead dose it at twice a day—same medication for the same indication—adherence will consistently go up,” he said. Meanwhile, emerging evidence points to patient cost as a key to improving drug adherence. “We see that cost really plays into this metric in a lot of different ways,” Dr. Choudhry said.

For physicians, getting patients to take their medications is as important, and as confounding, as getting them to lose weight or stop smoking, he said. Studies that engaged physicians to improve drug adherence found they had little effect. “So doctors are bad at this,” Dr. Choudhry said.

Hence the appeal of VBID. “We know that cost is a driver of nonadherence,” he said. “When a population sample of patients are asked have you not taken a medicine because of cost in the last two years, about 30% said yes; skipped doses because of cost is a problem for about 25%; and about 15% said it’s a problem for them or their family to pay for drugs,” he said.

Drug adherence is most acute among the uninsured, with rates up to 60%, according to Dr. Choudhry, but insured patients are not immune. Harvard research has shown that up to 25% of people with managed-care coverage reported that drug cost is an issue for them. “Co-pays or co-insurance or other forms of patient cost sharing are really ubiquitous in the U.S. health-care system,” he said. “Cost sharing has this unintentional effect of not only reducing utilization rates of nonessential services, but also reducing utilization rates of essential services.”

The Appeal of VBID
VBID for prescription drugs appeals to payers, but adaptation has been slow. “Fifteen to 20% of employers have actually implemented a program to lower cost sharing for essential therapies,” Dr. Choudhry said. “But if you look at those who are interested in doing it, the Mercer survey [of large employers] showed that 81% are interested in this concept.”(2)

A legion of barriers exist, as documented by A. Mark Fendrick, MD, of the University of Michigan in his 2009 report.(7) Mark V. Pauly, PhD, LDI Senior Fellow and Wharton School professor pointed out another hurdle to eliminating co-pays for certain classes of drugs and specific patients: “The usually story was, why do we charge $10 across the board? Well, it’s administratively simple.”

Targeted Therapies
Dr. Choudhry outlined five specific drug groups well suited to VBID: statins for high-risk cardiovascular disease, oral hypoglycemics for diabetes, anti-hypertensives for high blood pressure, inhalers for asthma, and anti-depressants for depression. “These are values that, based on what the medical evidence says, are incontrovertible, irrefutable examples of good quality care,” he said.

The Pitney Bowes study looked at two types of drugs in post-heart attack patients: cholesterol-lowering statins, and the blood thinner clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi Pharmaceuticals Partnership).1 Besides the increase in statin adherence, the study showed that patients with lower co-pays had a compliance rate about 4% higher than those in the control group.

While his other studies have shown similar results, Dr. Choudhry is quick to admit that the jury is still out on the true cost benefits of VBID and prescription drugs. A trial his group is now conducting with Aetna subscribers may provide some answers. He cited the potential per patient savings of $5,974 from his 2007 Health Affairs study.(3) “The reason why we’re doing this trial is that no one completely believes this number, myself included,” he said.
That trial may yet make him a believer.


  1. Choudhry NK, Fischer MA, Avorn J, et al. At Pitney Bowes, value-based insurance design cut copayments and increased drug adherence. Health Affairs. 2010;29:1995–2001.
  2. Choudhry NK, Rosenthal MB, Milstein A. Assessing the evidence for value-based insurance design. Health Affairs. 2010;29:1988-2994.
  3. Choudhry NK, Avorn J, Antman EA, Schneeweiss S, Shrank WH. Should patients receive secondary prevention medications for free after a myocardial infarction? An economic analysis. Health Affairs. 2007;26:186-94.
  4. Benner JS, Glynn RJ, Morgun H, Neumann PJ, Weinstein MC, Avorn J. Long-term persistence in use of statin therapy in elderly patients. J Am Med Assn. 2002;288:455-461.
  5. Choudhry NK, Setoguchi S, Levin R, Winkelmayer WC, Shrank WH. Trends in adherence to secondary prevention medications in elderly post-myocardial infarction patients. Pharmacoepidemiol Drug Saf. 2008;17:1189-96.
  6.  Sokol MC, McGuigan KA, Verbrugge RR, Epstein RS. Impact of medication adherence on hospitalization risk and healthcare cost. Med Care. 2005;43:521–530.
  7. Fendrick MA. Value-Based Insurance Design Landscape. National Pharmaceutical Council, Washington, DC; and Center for Value-Based Insurance Design, University of Michigan, Ann Arbor. 2009.

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