Study: Narrow pharmacy benefit networks improve medication adherence

Though there are growing concerns about narrow or preferred pharmacy networks, a CVS Health Research Institute study published in JAMA Internal Medicine finds that such networks actually improve members' medication adherence.

The study examines pharmacy claims data for more than 200,000 patients being treated for chronic high cholesterol, high blood pressure, diabetes and depression over a 12-month period. These patients received prescription drug coverage through CVS/caremark, the pharmacy benefit management business of CVS Health.

Out of the two narrow network and three non-network plans analyzed, individuals enrolled in narrow-network plans had greater increases in medication-possession ratio than those in non-network plans.

Additionally, there was an even greater impact on adherence when there were 90-day prescription programs also in place.

"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," study author William H. Shrank, M.D., senior vice president and chief scientific officer of CVS Health, says in an announcement.

Based on the results, the authors write that health plans and payers should consider narrow network pharmacy benefit designs, as they allow members to optimize drug adherence and reduce overall healthcare costs. Many insurers already have embraced narrow networks in their health plan offerings, as a recent report found that 41 percent of silver plans on Affordable Care Act exchanges had small or extra-small networks.

For more:
- here's the JAMA study (subscription required)
- check out the CVS Health announcement