Does the Cost of Preventive Drugs Change Health Outcomes?

Eliminating co-payments for drugs that can prevent heart attacks, strokes, or hospital visits had little impact on health outcomes among low-income seniors with chronic disease in Canada, according to a study unveiled Sunday at the 72nd American College of Cardiology (ACC) Annual Scientific Sessions Together With the World Congress of Cardiology.

The ACCESS trial, presented by Braden Manns, MD, MSc, professor of medicine at the University of Calgary, in Alberta, Canada, saved participants an average of 35 Canadian dollars, or $26, each month for 3 years. Manns said that the study was developed after earlier work showed seniors cited cost as a factor in poor adherence to medications to lower blood pressure or cholesterol or to treat diabetes.

But when given the chance to get drugs for free, those in the intervention group showed only a small uptick in adherence and no significant benefits in the study’s primary end point, a combined rate of death, heart attack, stroke, coronary revascularization, or hospitalization for cardiovascular-related conditions such as heart failure, coronary artery disease, or diabetes.

“Most experts in health policy will actually be quite surprised by this,” Manns said. “It’s a negative trial but still one that we can learn a lot from.”

The findings show the complex challenge of improving medication adherence among the most fragile members of society, as Manns noted that those with the lowest incomes were least likely to show any benefit.

“There was not even a signal of benefit in those groups,” he said during a press conference after presenting the findings. “Interestingly, in recent studies looking at financial interventions for people with food insecurity and diabetes, it's just the same thing actually—the people with the greatest financial barriers don't benefit.”

The takeaway, Manns said, may be “that people experiencing the greatest financial barriers have a lot of other barriers.”

In fact, Manns and his coauthors published their findings in Circulation¹ alongside a tandem study that measured the effects of an advertising campaign to promote adherence—and found this created a small but measurable positive effect on health outcomes.² However, that intervention offered positive messages only—not free drugs.

For A. Mark Fendrick, MD, director of the Center for Value-Based Medicine and a professor at the University of Michigan, these results highlight the complexity of addressing medication adherence.

“This study adds to a robust body of evidence showing that the elimination of consumer cost sharing leads to a modest increase in medication adherence,” said Fendrick, a co–editor in chief of The American Journal of Managed Care®. “The fact that over one quarter of individuals don’t take their essential medications even when free suggest that additional interventions—such as education regarding benefits and side effects, as well as efforts to address literacy—are needed.”

Improving adherence to preventive medications that could reduce the number of cardiac events among people with chronic diseases such as heart disease, diabetes and chronic kidney disease—or slow progression of these conditions to forestall the need for costly treatments such as insulin or dialysis—is one of the most vexing problems in medicine. About 1 in 8 people with chronic conditions cite cost as a primary reason for not taking preventive medications as prescribed, and people of lower socioeconomic status tend to have worse outcomes from chronic diseases than wealthier people.

As Karol Watson, MD, of UCLA, pointed out during the late-breaking session where the Calgary results were presented, this is not the first time for this type of finding. “One of the things that struck me the most was actually the dismal adherence rates for everyone whether they had co-pays or not,” she said.

In a well-known intervention funded by the National Institutes of Health in Camden, New Jersey, patients identified as “superutilizers” of the emergency department were targeted for intensive interventions and wrap-around services, yet readmission rates did not fall.³

In the Calgary study, investigators enrolled 4761 people aged 65 and over with an annual household income below the equivalent of $37,400 in the United States. All participants were at high cardiovascular risk, as defined by a combination of diagnosed chronic conditions or risk factors such as smoking, high blood pressure and elevated low-density lipoprotein (LDL) cholesterol.

As Manns explained, costs for the study were kept low; patients signed up to participate at the study at their local pharmacies with the possibility of getting free drugs, with those assigned to the intervention arm informed by mail that their co-payment would be eliminated for 3 years. A total of 15 drug classes were covered by the intervention.

The study used administrative and pharmacy records to track admissions and procedures and medication adherence. Results were as follows:

• The rate of the primary outcome was not reduced by eliminating co-payment. The intervention arm had 521 events vs 533 events in the usual cost-sharing arm, for an incidence rate ratio (IRR) of 0.84; 95% CI, 0.66-1.07, P = .162.
• The IRR rate for non-fatal myocardial infarction, non-fatal stroke, and cardiovascular death did not differ between the groups (0.97; 95% CI, 0.67-1.39) nor did death (0.94; 95% CI, 0.80-1.11) or cardiovascular-related hospitalization (0.78; 95% CI, 0.57-1.06).
• No significant between group changes in quality of life were seen.
• The share of patients with adherence to statins was 0.72 for the copayment elimination group vs 0.69 usual cost-sharing group, for a mean difference of 0.03; 95% CI, 0.006-0.06, P = .016.
• Overall adjusted care costs did not differ.

Lee Goldberg, MD, MPH, of the University of Pennsylvania, said during the press conference that the findings show why it’s important to test questions. “If you would have asked me about this trial upfront, I would have said 'Oh, the answer is obvious. If we remove the barrier to cost, everything will be fine.’ And you know, it didn't lead to the expected outcome. We didn't see the benefit that we expected to, and explaining that it's going to be critically important.

There are many factors impacting adherence, in addition to out-of-pocket costs, such as side effects, patient trust, cultural belief systems, cognitive challenges of patients, and more, he said.

“I think that what we're seeing here is that medication adherence is actually very complex,” Goldberg said.

This article originally appeared on AJMC.

References

1. Campbell DJT, Mitchell C, Hemmelgarn BR, for the Interdisciplinary Chronic Disease Collaboraton. Eliminating medication copayments for low-income older adults at high cardiovascular risk: a randomized controlled trial. Circulation. Published online March 5, 2023. doi:10.1161/CIRCULATIONAHA.123.064188
2. Campbell DJT, Tonelli M, Hemmelgarn BR, for the Interdisclipinary Chronic Disease Collaboration. Self-management support using advertising principles for older low-income adults at high cardiovascular risk: a randomized controlled trial. Circulation. Published online March 5, 2023. doi:10.1161/CIRCULATIONAHA.123.064189
3. Finklestein A, Taubman S, Doyle J, Health care hotspotting—a randomized controlled trial. N Engl J Med. 382:152-162. doi:10.1056/NEJMsa1906848