The mediating role of effective treatments in the relationship between income level and survival in patients with heart failure: a sex- and cohabitation-stratified study

Influence of socioeconomic status on rates of advanced heart failure therapies

BACKGROUND

Socioeconomic deprivation is associated with a lower likelihood of referral for advanced heart failure (HF) evaluation, but it is not known whether it influences rates of advanced HF therapies independently of key hemodynamic measures and comorbidity following advanced HF evaluation in a universal healthcare system.

METHODS

We linked data from a single-center Danish clinical registry of consecutive patients evaluated for advanced HF with patient-level information on socioeconomic status. Patients were divided into groups based on the level of education (low, medium, and high), combined degree of socioeconomic deprivation (low, medium, and high), and household income quartiles. Rates of the combined outcome of left ventricular assist device implantation or heart transplantation (advanced HF therapy) with death as a competing risk were estimated with cumulative incidence functions, and Cox proportional hazards models adjusted for age, sex, central venous pressure, cardiac index, and comorbidities.

RESULTS

We included 629 patients, median age 53 years, of whom 77% were men. During a median follow-up of 5 years, 179 (28%) underwent advanced HF therapy. The highest level of education was associated with higher rates (high vs low, adjusted HR 1.81 95% CI 1.14-2.89, p = 0.01), whereas household income quartile groups (Q4 vs Q1, adjusted HR 1.37 95% CI 0.76-2.47, p = 0.30) or groups of combined socioeconomic deprivation (high vs low degree of deprivation, adjusted HR 0.86 95% CI 0.50-1.46, p = 0.56) were not significantly associated with rates of advanced HF therapy.

CONCLUSIONS

Patients with a lower level of education might be disfavored for advanced HF therapies and could require specific attention in the advanced HF care center.

Recent successes in heart failure treatment

Remarkable recent advances have revolutionized the field of heart failure. Survival has improved among individuals with heart failure and a reduced ejection fraction and for the first time, new therapies have been shown to improve outcomes across the entire ejection fraction spectrum of heart failure. Great strides have been taken in the treatment of specific cardiomyopathies such as cardiac amyloidosis and hypertrophic cardiomyopathy, whereby conditions once considered incurable can now be effectively managed with novel genetic and molecular approaches. Yet there remain substantial residual unmet needs in heart failure. The translation of successful clinical trials to improved patient outcomes is limited by large gaps in implementation of care, widespread lack of disease awareness and poor understanding of the socioeconomic determinants of outcomes and how to address disparities. Ongoing clinical trials, advances in phenotype segmentation for precision medicine and the rise in technology solutions all offer hope for the future.

Non-Persistence with Medication as a Mediator for the Social Inequality in Risk of Major Adverse Cardiovascular Events in Patients with Incident Acute Coronary Syndrome: A Nationwide Cohort Study

Aim

Low socioeconomic status is associated with higher risk of major adverse cardiovascular events (MACE) among patients with incident acute coronary syndrome (ACS). We examined whether non-persistence with antiplatelet and statin therapy mediated the income- and educational-related inequality in risk of MACE.

Methods

Using national registers, all Danish patients diagnosed with incident ACS from 2010 to 2017 were identified. The primary outcome (MACE) comprised all-cause death, cardiac death and cardiac readmission. Risk of MACE was handled by discrete time analyses using inverse probability of treatment weights. The mediator variable comprised non-persistence to a combined 2-dimensional measure of statin and antiplatelet treatment. The mediation analysis was evaluated by population average effects.

Results

The study population was 45,874 patients, of whom 16,958 (37.0%) were non-persistent with medication and 16,365 (35.7%) suffered MACE during the median follow-up of 3.5 years. Compared to patients with low income, the adjusted hazard ratio of MACE was lowered by 33% (HR: 0.67, 95% CI: 0.61–0.72) in men and by 34% (HR: 0.66, 95% CI: 0.61–0.72) in women with high income, respectively. Similar results were observed according to level of education. A socioeconomic difference in risk of non-persistence was found in men but not women and only in relation to income. The lower risk of non-persistence observed in high-income men mediated the lower risk of MACE by 12.6% (95% CI: 11.1–14.1%) compared with low-income men.

Conclusion

Non-persistence with medication mediated some of the income-related inequality in risk of MACE in men, but not women, with incident ACS.