Changing patterns of cardiovascular risk factors and heart related sickness in relation with acute myocardial infarction in Delhi, India.

In this article an attempt has been made to investigate the 10-year trend of cardiovascular risk factors and common heart related sickness including angina, arrhythmias and congestive heart failure, and to study the impact of cardiovascular risk factors and heart related sickness on time between two acute myocardial infarctions. Chi-square test showed that in comparison to two 5-year study periods, the proportion of smoking, arrhythmias and congestive heart failure increased significantly in the second 5-year study period and the proportion of hypertension decreased significantly in the second 5-year study period. Moreover, with regard to occurrence of myocardial infarction under the age of 45 years, the prevalence decreased significantly in the second 5-year period. Cox regression model with time dependent covariates showed that gender, hypercholesterolaemia, congestive heart failure and arrhythmias were found to be important predictors associated with reduced time to second episode of myocardial infarction. The purpose of this study will help the physicians to detect the risk factors associated with reduced time between two myocardial infarctions after the occurrence of first episode of myocardial infarction so that by controlling the risk factors will either increase the duration between two myocardial infarctions or prevent the occurrence of second episode and hence improving the survival time of the patients.