Factors associated with medication refill adherence in cardiovascular-related diseases

Abstract

BACKGROUND: The factors influencing medication adherence have not been fully elucidated. Inadequate health literacy skills may impair comprehension of medical care instructions, and thereby reduce medication adherence. OBJECTIVES: To examine the relationship between health literacy and medication refill adherence among Medicare managed care enrollees with cardiovascular‐related conditions. RESEARCH DESIGN: Prospective cohort study. SUBJECTS: New Medicare enrollees from 4 managed care plans who completed an in‐person survey and were identified through administrative data as having coronary heart disease, hypertension, diabetes mellitus, and/or hyperlipidemia (n=1,549). MEASURES: Health literacy was determined using the short form of the Test of Functional Health Literacy in Adults (S‐TOFHLA). Prospective administrative data were used to calculate the cumulative medication gap (CMG), a valid measure of medication refill adherence, over a 1‐year period. Low adherence was defined as CMG≥20%. RESULTS: Overall, 40% of the enrollees had low refill adherence. Bivariate analyses indicated that health literacy, race/ethnicity, education, and regimen complexity were each related to medication refill adherence (P<.05). In unadjusted analysis, those with inadequate health literacy skills had increased odds (odds ratio [OR]=1.37, 95% confidence interval [CI]: 1.08 to 1.74) of low refill adherence compared with those with adequate health literacy skills. However, the OR for inadequate health literacy and low refill adherence was not statistically significant in multivariate analyses (OR=1.23, 95% CI: 0.92 to 1.64). CONCLUSIONS: The present study suggests, but did not conclusively demonstrate, that low health literacy predicts poor refill adherence. Given the prevalence of both conditions, future research should continue to examine this important potential association.

The Demographic Assessment for Health Literacy (DAHL): A New Tool for Estimating Associations between Health Literacy and Outcomes in National Surveys

“…13 Non-respondents were slightly older with higher educational attainment and were more likely to be white and living in zip codes with higher median income 10 . Additional details of this survey have been published previously 6,10,[14][15][16][17][18] . Starting with this sample of 3,260, we excluded 282 subjects with history of stroke, 55 with severe cognitive impairment (MiniMental State Examination Score<18), and 99 with a missing value in one of the fields examined in this study 18,19 , leaving a final analytic sample of 2,824.…”

Medication Adherence Does Not Explain Black-White Differences in Cardiometabolic Risk Factor Control among Insured Patients with Diabetes

“…One study that has done so did not explore differences by patient race. 44 The complex mix of patient, physician, and system factors associated with both medication adherence [45][46][47] and treatment intensification 42,[48][49][50] has been well documented, as have the ongoing challenges in achieving clinical control even when patients are adherent and treatment is intensified. 44,51,52 It is therefore encouraging to see that within a relatively short follow-up period, a substantial percentage of patients who were in poor control at baseline were able to achieve recommended control levels.…”

Targeting Low HDL-Cholesterol to Decrease Residual Cardiovascular Risk in the Managed Care Setting

“…In the managed care setting, evidence indicates that education for patients can improve statin treatment adherence and, in turn, increased medication adherence is associated with a greater likelihood of achieving LDL-C goals. 8,9 Parris et al showed that medication adherence did not significantly differ among patients receiving atorvastatin, pravastatin, or simvastatin, and no significant differences were seen in mean LDL-C levels. 9 However, LDL-C goal attainment is of substantial concern in managed care and has been shown to be suboptimal, especially in high-risk patients.…”