The article by Vellakal et al [1] is consistent with our earlier published studies which reported that risk factors of cardiovascular diseases (CVD) and other non-communicable diseases (NCDs) are presently showing a pattern of reversed social gradient in India, with higher prevalence among the poor [2, 3]

However, the relevant references from our studies [2] as well as those of Gupta et al [4, 5] have been incorrectly cited by Vellakal et al. The authors state, in the Discussion section of the paper, that references 69,70,71 have 'demonstrated the increased risk of cardiovascular disease and cardiovascular risk factors in affluent groups'. The cited studies, in fact, demonstrate the contrary and are in line with the present study.

Interestingly, the second author of the present study (S.V. Subramanian) recently co-authored a commentary which challenged these previous Indian studies by us [2, 3] and Gupta et al [4, 5], arguing that CVD risk could not be higher among the poor since they had lower rates of obesity [6]. The study by Vellakal et al, to which Subramanian is a major contributor, should help to correct that critique. Apart from identifying the fallacy of self reported measures of risk, the present study should also remind us that obesity is neither the sole nor the best predictor of CVD risk in India.

On behalf of K. Srinath Reddy, Panniyammakal Jeemon and Dorairaj Prabhakaran (Public Health Foundation of India, New Delhi and Centre for Chronic Disease Control, New Delhi, India).

References

1. Vellakkal S, Subramanian SV, Millett C, Basu S, Stuckler D, Ebrahim S. (2013) Socioeconomic Inequalities in Non-Communicable Diseases Prevalence in India: Disparities between Self-Reported Diagnoses and Standardized Measures. PLoS ONE 8(7): e68219. doi:10.1371/journal.pone.0068219.

2. Reddy KS, Prabhakaran D, Jeemon P, Thankappan KR, Joshi P, Chaturvedi V,Ramakrishnan L, Ahmed F. (2007) Educational status and cardiovascular risk profile in Indians. Proc Natl Acad Sci U S A 104(41):16263-8.

3. Jeemon P, Reddy KS. (2010) Social determinants of cardiovascular disease outcomes in Indians. Indian J Med Res. 132:617-22.

4. Gupta R, Kaul V, Agrawal A, Guptha S, Gupta VP (2010) Cardiovascular risk according to educational status in India. Prev Med 51: 408–411. doi: 10.1016/j.ypmed.2010.08.014.

5. Gupta R, Gupta VP, Sarna M, Prakash H, Rastogi S, et al. (2003) Serial epidemiological surveys in an urban Indian population demonstrate increasing coronary risk factors among the lower socioeconomic strata. J Assoc Physicians India 51: 470–477.

6. Subramanian S, Corsi DJ, Subramanyam MA, Davey Smith G. (2013) Jumping the gun: the problematic discourse on socioeconomic status and cardiovascular health in India. Int J Epidemiol:1-17. doi: 10.1093/ije/dyt017.