Explaining the Decline in Coronary Heart Disease Mortality Rate Using IMPACT Model: Estimation of the Changes in Risk Factors and Treatment Uptake in Iran between 2007 and 2016.

Introduction: Coronary heart disease (CHD) contributes significantly to mortality and morbidity in Iran. A model was fitted in this study to determine changes in risk factors and treatment uptake to CHD mortality rate reduction in Isfahan between 2007 and 2016.

Method: The IMPACT model was fitted to determine how much the decrease in CHD death can be explained by treatment uptake and significant risk factors included in the analyses for adults aged 35 to 84 years. Body mass index (BMI), diabetes, and smoking were considered as the CHD risk factors in the model. Medical and interventional treatments were studied in four different groups of patients. The primary data sources were obtained from the Persian registry of cardiovascular disease (PROVE), The Isfahan healthy heart program (IHHP), and the impact of self-care management and adopted Iranian guidelines for hypertension treatment on improving the control rate of hypertension (IMPROVE CARE) study, death registration system, and the Isfahan province Cemetery.

Results: The CHD mortality rate decreased by 14% between 2007 and 2016 in Iran for adults aged 35 to 84 years and prevented or delayed 212 CHD deaths in 2016. Treatment uptakes caused 99% postponed or prevented death. Treatment for heart failure in hospitals explained approximately half of the death prevented by treatment. Risk factors caused about 15% of excess death. It appears that the prevalence of CHD is increasing while the death rate is decreasing because of these observed changes.

Conclusion: Risk factors worsened in 2016 and, without treatment, could lead to an increase in CHD mortality in Iran. Preventive policies should control the risk factor and contribute to the decrease in CHD death.