Most reports of mortality studies in patients with heart failure come from developed countries, such as North America and Europe. A new study looks at mortality rates in heart failure patients from countries such as Africa, China, India, the Middle East, Southeast Asia and South America.
Cardiac disease is a global phenomenon, afflicting 26 million people worldwide. However, a large majority of observational and clinical studies in patients with heart failure take place in high-income nations in Europe, or in the US. Data from middle and low-income countries is crucial for estimating the global toll of heart failure.
In a new paper published in The Lancet, pharmaceutical giant Novartis reported its findings from The International Congestive Heart Failure Study (INTER-CHF), a prospective cohort study conducted in 108 centers spanning 16 different countries. It documented mortality rates in Africa, India, Southeast Asia, China, South America and the Middle East, in patients suffering from heart failure. A total of 5823 patients were enrolled in the study, with a follow-up rate of 98%. Baseline demographic and clinical characteristics were recorded at the initiation of the study, and patients were followed up with at 6 months and 1 year.
The study revealed that the overall global mortality rate was 16.5%, with highest percentages coming from Africa (34%) and India (23%). Mortality rates were intermediate in Southeast Asia (15%) and lowest in China (7%), South America (9%) and the Middle East (9%). Importantly, patients in Africa were younger, more symptomatic, often from a rural area and had little education. A similar pattern was observed in India.
About 46% of the overall mortality risk was explained by cardiac (previous history of heart failure, valve disease etc.) and non-cardiac (body mass index, chronic kidney disease, and chronic obstructive pulmonary disease) variables. However, the remainder was unexplained and proposed to result from socioeconomic variables such as access to healthcare, quality of care and environmental factors. The higher mortality rate in Africa and India could also be due to patients reporting to a healthcare professional at a later stage, when the disease had progressed to a stage of worse prognosis. Additionally, genetic makeup was also hypothesized to play a role.
The findings warrant further global prospective studies in larger cohorts, taking into consideration the socioeconomic and genetic factors that make up the population.
Written By: Debapriya Dutta, PhD