Study Finds Association Between Neighborhood-Level Socioeconomic Status, Medication Nonadherence Among Heart Failure Patients

Recently published research points to a need for greater outreach efforts to improve medication uptake among underserved patient populations. In a JAMA Network study published last week, the authors set out to discover whether medication nonadherence amongst patients with heart failure (HF) correlates with neighborhood socioeconomic status (nSES).¹

To find the answers they were looking for, the authors implemented a retrospective cohort study conducted between June 30, 2020, and December 31, 2021, among 6247 patients with HF with reduced ejection fraction. Patient addresses were geocoded, and nSES was calculated using the Agency for Healthcare Research and Quality SES index, which combines census-tract level measures of poverty, rent burden, unemployment, crowding, home value, and education, with higher values indicating higher nSES.¹

The results found that patients living in neighborhoods with lower nSES had significantly higher odds of nonadherence to guideline-directed medical therapy for HF, with medication nonadherence being measured through the proportion of days covered (PDC) metric, with nonadherence defined as PDC < 80% over six months. Patients in lower nSES areas tended to be younger, of Black or Hispanic/Latinx ethnicity, with Medicaid insurance, lower left ventricular ejection fraction, and lower comorbidity index scores.¹

According to a 2021 article by Medical News Today, numerous other reasons were given for adherence issues among underserved patient populations, with approximately 40%-50% of people not taking their prescribed medication. Examples for nonadherence include completely forgetting to take the medication, personal concerns and experiences, cost and systemic factors, and effects on health and healthcare.²

“Improving medication adherence is no easy task. It may involve asking a person to go against their cultural or ethnic practices and may even involve restoring trust in the medical community after years, and generations, of racism and other forms of discrimination,” writes Jennifer Huizen, author of the Medical News Today article. “Also, adherence might involve small changes, such as using an alarm or another medication reminder, but it might involve substantial changes to dietary or lifestyle habits. Several factors, including education, support systems, medical monitoring, motivation, and evaluations of effectiveness, may be involved in improving adherence.”²

The authors of the JAMA study stressed the fact that access to transportation and pharmacy density did not significantly mediate the association. However, walkability showed a small but statistically significant mediation effect, contributing to approximately 7% of the variability in nonadherence probability.¹

“Overall, the association between nSES and medication nonadherence is likely multifaceted and due to complex, dynamic interactions between environmental, individual, and cognitive factors,” the authors wrote. “Neighborhood-level factors include environmental stressors, such as violence and perceived safety, which could serve as physical barriers to obtaining medications, and also act as emotional stressors that drain one’s capacity for adherence in the setting of immediate threat. Additionally, built environment factors, such as access to transportation, walkability, and could impede interactions with health care professionals to discuss medication-related concerns.”

Acknowledging the study’s limitations, the authors referenced the fact that it was a retrospective cohort study conducted across a single health system in an urban environment. They didn’t assess whether medications were delivered by mail or not. As a result of the electronic health record data, they also weren’t able to account for time since HF diagnosis or HF treatment history.¹

In conclusion, the study states that future initiatives should focus on identifying and addressing neighborhood-level barriers to adherence. The study highlights an important gap that may contribute to known neighborhood-level disparities in HF care and outcomes.¹

References

1. Neighborhood-Level Socioeconomic Status and Prescription Fill Patterns Among Patients With Heart Failure. JAMA Network. December 14, 2023. Accessed December 18, 2023. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2812884

2. Taking drugs as advised: What are the barriers? Medical News Today. April 12, 2021. Accessed December 18, 2023. https://www.medicalnewstoday.com/articles/taking-drugs-as-advised-what-are-the-barriers