Study examines prescription refill patterns of chronic therapy patients

WOONSOCKET, R.I. — The first prescriptions filled by patients with chronic conditions provide a good sign of how well they will adhere to their medications, according to research by CVS Health.

CVS said Monday that a new study by the CVS Health Research Institute and Brigham and Women’s Hospital revealed that patients’ patterns of medication fills in the first few months after starting on a chronic therapy accurately predict future medication adherence behavior.

Published in the American Journal of Managed Care, the study indicates that assessing behavior with initial fills may help quickly identify chronic therapy patients most likely to benefit from medication adherence interventions.

“With the increasing availability of rich patient data, we can better anticipate how the patients we manage will take their medications,” stated study senior author Niteesh Choudhry, associate physician in the division of pharmacoepidemiology and pharmacoeconomics at Brigham and Women’s Hospital and associate professor at Harvard Medical School. “This research shows that by focusing on a patient’s initial, short-term medication filling behavior — are they or are they not refilling their prescription on time during the first few months of therapy — we can predict with great precision whether a patient will continue to take the medication as prescribed over the long-term.”

The study included claims data from more than 77,000 Medicare beneficiaries that began taking a statin or statin combination drug over a three-year period and whose pharmacy benefits are administered by CVS/caremark. Based on patterns of prescription filling over the year after therapy initiation, researchers used group-based trajectory models to classify patients into six adherence trajectories, ranging from nonadherent to near-perfect adherence, to help capture the duration and intensity of medication taking.

CVS said the results showed that patient patterns of initial medication filling in the first two to four months after initiation of a prescription accurately predicted future adherence, enabling precise prediction of the patterns of medication taking over the ensuing year. The company noted that the research further validates group-based trajectory modeling as an accurate approach to classify patient medication adherence behaviors.

“This approach is helping us better target interventions to those patients who are most likely to benefit because trajectory modeling differentiates between patients who struggle with adherence at different times during their treatment,” explained study co-author William Shrank,  senior vice president and chief scientific officer at CVS Health. “It can also be easily replicated and available to support a wide spectrum of payors and providers who are attempting to improve the quality and reduce the costs of health care. Increasingly, we are finding that, through better analytics, we can deliver the right intervention to the right patient at the right time.”

CVS added that it’s employing advanced analytics to more effectively target medication adherence interventions, improve health outcomes and rein in health care costs. The company recently launched the Vulnerable Patient Index (VPI), a tool that leverages pharmacy claims data to risk-stratify patients and identify CVS/caremark members most likely to generate high overall health care costs due to poor adherence or unsafe use of complex medication regimens.