WOONSOCKET, R.I. — Narrow pharmacy networks improve medication adherence, according to a new CVS Health Research Institute study published Tuesday in JAMA Internal Medicine. The study is the first to evaluate the impact of narrow pharmacy networks on medication adherence, the company stated.
In addition, the researchers observed an even greater impact on adherence when there were 90-day prescription programs also in place.
"There are few opportunities in health care when we can improve both quality of care and health outcomes while helping to manage health care costs," stated William Shrank, SVP and chief scientific officer, CVS Health and a study author. "This first-of-its-kind study suggests that narrow networks may be one such opportunity by providing clear evidence that these networks – already an established cost management strategy – also help optimize members' adherence."
The researchers reviewed de-identified pharmacy claims data for more than 200,000 patients on chronic therapies to treat high cholesterol, high blood pressure, diabetes and depression over a 12-month period. These patients received prescription drug coverage through CVS' pharmacy benefit management business CVS/caremark. The study found that those patients in commercial drug plans with narrow pharmacy networks had improved medication adherence as indicated by their medication possession ratio, which measures patients' available medication on hand over time and is commonly used as an indication of adherence.
The researchers also found that if 90-day prescription programs, where patients receive a three-month supply of their chronic medication prescription during one pharmacy visit, were used in conjunction with a narrow network there was an even greater improvement in members' adherence.
"Despite common concerns that narrow pharmacy networks reduce access, we believe they can actually help encourage plan members to establish a pharmacy home where patients with chronic diseases can receive coordinated care and effective medication adherence support," Shrank said.