Heart failure is a major public health burden in many low- and middle-income countries (LMICs), with substantial variation in the presentation, causes, management, and outcomes of heart failure across different LMICs, according to a study published in this week's PLOS Medicine. The study, led by Kazem Rahimi and colleagues from the George Institute for Global Health, also finds that a large proportion of patients are not receiving pharmacological treatments for heart failure.
The researchers conducted a systematic review and identified 49 published studies and 4 unpublished databases covering 31 countries and 237,908 hospitalizations for heart failure. By pooling the data from these studies, they found that the average age of patients admitted for acute heart failure was 63 years, which ranged from 42 years in Cameroon and Ghana to 75 years in Argentina, and correlated with the human development index (a measure of national well-being) of individual LMICs. The leading causes of heart failure differed across countries, with ischemic heart disease the most common cause in countries outside of Africa and the Americas, hypertension the most dominant cause in Africa (46%), and hypertension and ischemic heart disease similarly common in the Americas (31 and 33%, respectively). While 69% of heart failure patients in LMIC were prescribed diuretics, the three main treatments currently recommended in guidelines for managing heart failure -- angiotensin converting enzyme inhibitors, beta-blockers, and mineralocorticoid receptor agonists -- were prescribed at lower rates (57, 34, and 32%, respectively).
While the findings indicate that the burden of heart failure is substantial in LMICs, data from all LMICs were not available and the estimates are mostly derived from urban tertiary referral hospitals, therefore these findings may not reflect the broader picture of heart failure in the community in LMICs. The limited available data on and substantial impact of heart failure in LMIC emphasizes the need for more research attention in this area.
The authors stress the importance of this public health issue: "This review shows that heart failure places a considerable burden on health systems in LMICs, and affects a wide demographic profile of patients in these countries."
In a linked Perspective, Druin Burch examines how inconsistencies in diagnosis and selection of patients for clinical trials may contribute to treatment burden of heart failure in LMICs, saying: "The gap between suboptimal treatment of heart failure and what is achievable represents not just a failure to practice evidence-based medicine but a greater gap in knowledge and the research agenda."
Funding: This work was supported by the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre Programme and NIHR Career Development Fellowship. KR and SM are supported by the Oxford Martin School and the George Institute for Global Health. The researchers conducted this study totally independently of the funding bodies. No funding bodies had any role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: CL is funded by a Clinician Scientist Award from the National Medical Research Council of Singapore; receives research grants from Boston scientific, Medtronic, and Vifor Pharma; and serves as a consultant for Bayer and Novartis. JML is employed by the contract research organization Effi-Stat, which receives funding from pharmaceutical and biotechnology companies. In 2009 and 2010 Effi-Stat received financial support from Sanofi Aventis for providing statistical analysis and programming for the I-Prefer study included in this review (reference ). SG is employed by the contract research organization Effi-Stat, which receives research funding from pharmaceutical and biotechnology companies. AP is a member of the Editorial Board of PLOS Medicine.