PATTERNS OF COST-RELATED MEDICATION NON-ADHERENCE AMONG OLDER PATIENTS AT HIGH RISK OF HOSPITALIZATION

Purpose: Up to one third of older patients report cost-related medication non-adherence (CRN). However, little is known about the patterns of CRN, especially among high-risk patients, among whom CRN may have the greatest adverse effects on health and healthcare or about the extent to which insurance coverage may be protective. We aimed to assess the patterns of CRN behavior among high-risk Medicare patients and test if additional Medicaid coverage is protective for CRN.

Method: Older Medicare patients at high risk of hospitalization in an urban teaching hospital were enrolled based upon their likelihood of having an average of 10 days of hospital days in a given calendar year. Patients were surveyed to assess four different types of CRN behaviors: not filling or refilling a prescription, delaying getting a prescription filled, skipping doses to make the medicine last longer, and/or taking smaller doses to make the medicine last longer.  We analyzed the rates of these behaviors and their combinations, and assessed if the addition of Medicaid coverage was associated with lower rates of CRN.   

Result: 524 eligible patients were surveyed, among whom 148 (28.2%) reported one or more CRN behaviors. The mean age of the full sample was 61.9 years (s.d. 16.6), with 320 (61%) female, and 240 (47.6%) with Medicaid coverage (i.e., dual eligible). Among these dual eligibles, 28% reported CRN, compared to 28% of those without Medicaid (p=0.98). Delaying filling of a prescription (22%) was the most prevalent CRN behavior, followed by not filling a prescription (19%), skipping doses (13%), and splitting doses to make the medicine last longer (13%). Among those who reported CRN, delaying getting a prescription was the single most prevalent CRN behavior (76%), but 58% reported two or more CRN behaviors, and 26% reported all of the four CRN behaviors.

Conclusion: CRN is highly prevalent among older Medicare patients at high risk of hospitalization, even those with Medicaid coverage. Among patients reporting CRN, delay in filling prescriptions is the most frequent CRN behavior, but multiple CRN behaviors are common. The frequency and extent of CRN in this population suggest the potential for large adverse effects of CRN and the likelihood that physicians may be inadequately aware or responsive to CRN behaviors. Patient-centered efforts to identify and address CRN deserve attention.