doi:10.1038/nindia.2018.81 Published online 26 June 2018
People from India’s northern, north-eastern and southern states have a higher risk of developing cardiovascular disease (CVD) than those in the rest of the country, a new large-scale population based study has revelaved1. The average risk of CVD varies greatly within the geography of India, ranging between 19.5% in the southern state of Kerala to 13.2% in the eastern state of Jharkhand, the study says.
Among the states with highest risk were Kerala in the south followed by the tourist hub of Goa, Nagaland in the northeast and Himachal Pradesh in the north. Also included in the high risk group were the other southern states, Punjab and Uttarakhand in north and the north-eastern states, except for Assam which showed a lower risk of CVD. West Bengal was the only eastern state listed in the high risk category.
Geographical differences became starker when the researchers included gender in the analysis. Across states, men had a higher risk of CVD than women. Women in Assam were found to have the lowest risk at 10.2% and men in Nagaland and Himachal Pradesh displayed a high risk of 24.2%, making almost a quarter of the male population in these states susceptible to CVD.
To estimate these population-wide risks for CVD, the researchers pooled data from India’s District Level Household Survey-4 (DLHS-4) and the second update of the Annual Health Survey (AHS). The study participants – a total of 797,540 men and women – were from all states and union territories of India, excluding J&K, Gujarat, Dadra & Nagar Haveli, and Lakshadweep, from where data was not available. For each individual, information on blood glucose, systolic BP, height and weight, age, sex, and smoking status were used to compute risk.
Besides gender, other socio-demographic factors, such as wealth also appeared to affect CVD risk. The researchers noticed that the rich often had high BMI while the poor typically had high blood glucose and high BP. They found a positive correlation between wealth of a district and its CVD risk -- wealthier the district, higher was its CVD risk. Interestingly, this correlation was more pronounced in rural India. It is likely that the “urban rich are generally well educated and aware of their health status but that may not always be true for the rural rich,” says Ashish Awasthi, one of the researchers and an assistant professor at the Public health Foundation of India. Smoking, which also increases overall CVD risk, was also more prevalent in rural areas (mostly among poor men) in comparison to the urban areas.
The urban rural divide was another determinator of CVD risk, with the rural populations having lower risk than their urban counterparts.
Awasthi hopes that this study will pave the way for national policy interventions that push for improved awareness about CVD and facilitate programmes to prevent, screen, and treat high risk populations.
“The need for addressing tobacco and hypertension as well as community environment are the two most important takeaways from this study for policy makers,” says Anand Krishnan, a professor at the Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi. “While we know what steps should be taken, the challenge is in translating them to action. We do not know the ‘hows’,” he says.
1. Geldsetzer, P. et al. Geographic and sociodemographic variation of cardiovascular disease risk in India: A cross-sectional study of 797,540 adults. PloS Medicine (2018) doi: 10.1371/journal.pmed.1002581