Background and Aims:
We determined what proportion of the mortality decline from 2014 to 2017 in coronary heart disease (CHD) in the west Delhi could be attributed to advances in medical treatment and to improvements in population-wide cardiovascular risk factors.

Methods:
We used the IMPACT-SEC model. Nationwide information was obtained on changes between 2014 and 2017 in the use of 56 treatments and in cardiovascular risk factor levels in adults, aged 24 or over. The primary outcome was the number of CHD deaths prevented or postponed.

Results
The age-standardized CHD mortality fell by 44% from 269 to 124 per 100.000, with remarkably similar relative declines across socioeconomic groups. This resulted in 11,800 fewer CHD deaths in 2016 than expected. The model was able to explain 76% of the mortality decline. Approximately 39% (95% CI: 10%-80%) of the decline was attributable to changes in acute phase and secondary prevention treatments: the largest contributions came from treating patients in the community with heart failure (15%) or chronic angina (12%). Approximately 33% (25%-66%) was attributable to decreases in risk factors: blood pressure (30%), total cholesterol levels (11%), smoking (8%) and physical inactivity (4%).Overall, these findings did not vary across socioeconomic groups, although within socioeconomic groups the contribution of risk factors differed.

Conclusions:
The mortality of CHD has recently halved in the west Delhi, India. Equally large contributions have come from the increased use of acute and secondary prevention treatments and from improvements in population risk factors. Increases in obesity and diabetes represent a major challenge for future prevention policies.

04 - DEMONSTRATING THE DECLINE IN CORONARY HEART DISEASE MORTALITY IN THE WEST DELHI, INDIA BETWEEN 2014 TO 2017