Challenge to research on heart disease patterns in India sparks controversy

BMJ 2013; 346 doi: (Published 15 May 2013) Cite this as: BMJ 2013;346:f3155
  1. Ganapati Mudur
  1. 1Delhi

A research review has sought a fresh assessment of cardiovascular disease patterns in India, claiming that doctors have argued that coronary heart disease and its risk factors disproportionately affect poor people in India without sufficient evidence.

The review has claimed that many studies looking at the distribution of cardiovascular disease and its risk factors across different socioeconomic sections of the population have drawn inferences that are “often discordant with their own results.”1

The evidence suggests that deaths from coronary heart disease occur disproportionately among economically advantaged groups, according to the review, which examined 53 studies, including 49 conducted since 1989. The review said that except for high rates of smoking and poor intake of fruits, the other risk factors such as obesity, elevated lipids, and hypertension are more prevalent among the higher socioeconomic groups than among the lower groups.

Subu Subramanian, a professor of population health at the Harvard School of Public Health and the review’s corresponding author, stated: “I think there has been an eagerness to declare a shift in the burden of heart disease in India from the rich to the poor.”

A study of industrial workers from 10 sites in India six years ago had, for example, mentioned a growing vulnerability of the lower socioeconomic groups to coronary heart disease. 2 But, the review said, this study had observed a positive association between socioeconomic status and body mass index, obesity, cholesterol, and triglycerides among men and a negative socioeconomic gradient for smoking, hypertension, and diabetes among women.

Daniel Corsi, a research fellow at the Harvard School of Public Health and a coauthor of the review paper, said: “Many of the Indian studies capture special populations that may not represent all of India, especially the very poor.”

Doctors who led these studies have asserted that India is indeed experiencing a reversal of the cardiovascular burden. Dorairaj Prabhakaran, professor of chronic disease epidemiology at the Public Health Foundation of India in New Delhi, said: “Everything doesn’t change all at once—tobacco use is the first risk factor to reverse—and we’re already seeing this. Hypertension follows, then diabetes, hyperlipidaemia, and obesity reverse last.”

But Subramanian said that there is not enough evidence to support such a sequence of reversal.

The review has expressed concern that the “haste” to suggest that cardiovascular diseases disproportionately burden poor people could increase inequity in healthcare by “unwittingly shifting limited resources from the health concerns of the poor to health concerns of the rich in India.”

It has called on India to invest in a rigorous surveillance programme for cardiovascular diseases, citing how India had to revise downward predicted estimates of HIV infections six years ago after improving mechanisms of HIV surveillance.3

Many doctors said that they believed a controversy over cardiovascular disease burden in India is unwarranted, given its large population, whether rich or poor.

Sanjay Kinra, a senior lecturer in non-communicable disease epidemiology at the London School of Hygiene and Tropical Medicine said: “There is really no need for any controversy. India has multiple shades of poverty, and what you see depends on where you look—it’s something like the blind men touching an elephant.”

Prashant Joshi, a professor of medicine at the Indira Gandhi Government Medical College in Nagpur, said: “The truth is that coronary heart disease and its risk factors remain undetected, untreated, or poorly managed in huge numbers of poor people because of lack of access to healthcare services.”

Doctors also pointed out that the presentation of cardiovascular diseases could differ across different sections of the population. Yogesh Jain, a paediatrician with Jan Swasthya Sahyog (people’s health support group), a non-government organisation that runs healthcare services for rural populations in the eastern state of Chhattisgarh, said: “We do see heart disease among the poor, but many among them have rheumatic heart disease. It is a large burden.”


Cite this as: BMJ 2013;346:f3155