Reducing or eliminating copayments for medications to treat common chronic conditions can improve medication adherence by several percentage points, according to a study published Nov. 2 in the journal Health Affairs.
"We observed improvements in adherence that were relatively modest in scale and that are consistent with the findings of other investigators," wrote lead author Dr. Niteesh Choudhry of Harvard Medical School, Boston, and his colleagues. "This highlights the various factors involved in nonadherence. Thus, the ability of benefit design and patient financial incentives to address this complex problem completely should not be overestimated."
The investigators manipulated medication copayments for a subset of employees of Pitney Bowes, a self-insured company. For a total of 2,830 employees, copayments for statins were eliminated and the copayment for clopidogrel was significantly reduced. Their medication adherence patterns were compared to 49,801 fellow employees whose copayments were not changed (doi: 10.1377/hlthaff.2010.0808).
To measure medication adherence, the study's authors estimated the number of days of medication each patient actually received through the pharmacy benefit manager, compared to the total number of days in each month between January 2006 and December 2007.
Adherence to statins rose by 3.1% immediately after the copayment was eliminated, compared to the control group. The number of patients who were fully adherent to their statin regimen rose by 17% immediately, compared to controls.
Meanwhile, when copayments were reduced for clopidogrel, adherence rates rose by 4.2% in the intervention group compared to the control group, according to the investigators. The number of patients who were fully adherent rose by 20% immediately, compared to the control group.
This type of value-based benefit design can improve compliance, but physicians and policymakers will need to address other compliance factors in order to have a major cost-saving effect, Dr. Choudhry wrote.
Cost definitely plays a role in patient adherence, but it's not the only factor, noted Dr. Melissa S. Gerdes, a family physician at Trinity Clinic Whitehouse, in Texas. "I get people who don't want to pay a $10 copay to see me, but who will go to McDonalds and drop $20," Dr. Gerdes said in an interview. "They – in general – consider anything over $10 as high for a copay."
Decreasing copayments from $50 to $30, for example, wouldn't make much difference, Dr. Gerdes said, because most patients can no more afford the $30 copayment than the $50 one. To make a real difference, copayments need to drop to around $4, the price Walmart charges for many generics, she said.
Dr. Dennis Saver, a family physician in Vero Beach, Fla., agreed, but added that the patients in Dr. Choudhry's study already were paying a reduced cost for their medications, and so "the effect may be diminished. If they did a study of someone paying $150 or $200 out of pocket for a medication and then bring that down to $15, they might see a greater effect," he said in an interview.
Finally, financial considerations in overall care compliance have a cascade effect, said Dr. Gretchen Dickson of the department of family medicine at the University of Kansas, Kansas City.
"A lot of factors play into it," Dr. Dickson said in an interview. "Not making appointments, not going in for testing, not filling the prescription – all just go along with not being compliant with your medication. What this shows us is, sometimes they just can't afford it."
The study was supported by the Commonwealth Fund. The authors disclosed grant funding from Aetna Inc. and the Robert Wood Johnson Foundation