Fifteen percent of myocardial infarctions and coronary revascularizations explained by family history unrelated to...

Area of Science:

• Cardiovascular Epidemiology
• Genetics of Heart Disease
• Preventive Cardiology

Background:

• Coronary heart disease (CHD) poses a significant global health burden.
• Family history is a known, yet often under-quantified, risk factor for CHD.
• Understanding the independent contribution of familial factors is crucial for risk stratification.

Purpose of the Study:

• To investigate the association between a family history of myocardial infarction (MI) and the risk of developing CHD.
• To determine if this association persists after accounting for established cardiovascular risk factors.
• To quantify the proportion of CHD cases attributable to family history.

Main Methods:

• Prospective cohort study of 9,328 men and 10,062 women (aged 33-81) in Reykjavik.
• Baseline cardiovascular risk assessment and collection of family history of MI via questionnaire.
• Long-term follow-up (18-19 years) to ascertain CHD events (MI or coronary revascularization).

Main Results:

• Individuals with a positive family history of MI had a significantly higher hazard ratio (HR) for CHD: 1.75 for men and 1.83 for women.
• Even after adjusting for other risk factors, the HR remained significant: 1.66 for men and 1.64 for women.
• Family history of MI accounted for 15.1% of CHD cases in men and 16.6% in women, independent of measured risk factors.

Conclusions:

• A positive family history of myocardial infarction is a substantial and independent risk factor for developing coronary heart disease.
• Approximately 15% of all coronary heart disease cases can be attributed to familial factors, highlighting the importance of genetic predisposition.
• Further research is needed to elucidate the specific genetic and unmeasured familial factors contributing to this increased risk.