Family history of cardiovascular disease and risk of premature coronary heart disease: A matched case-control study

Background

Self-reported
family history of cardiovascular disease (CVD) is an independent risk factor
for future coronary heart disease (CHD) events. However, inclusion of family
history of CVD in the traditional risk scores failed to improve risk prediction
of CHD. It is proposed that family history of CVD may substantially increase
the risk of CHD among younger individuals.

Methodology

We
conducted a matched case-control study with 170 hospital-based
premature CHD patients (<55 years in men and <65 years in women) from a
tertiary care centre in Thiruvananthapuram, Kerala and age and sex matched community-based controls in 1:1 ratio. Conditional
logistic regression analysis was conducted to assess the independent
association of family history of cardiovascular disease (CVD) and premature CHD.
We estimated McNemar's odds
ratios and their 95 percent confidence intervals.

Result

The prevalence of any family history of CVD and CHD in the control
population was 24% and 21%, respectively. The family history of CVD was independently associated with
premature CHD (OR = 9.0; 95%CI 4.7 – 17.3). There
was a dose response relationship between family history and premature CHD as
the risk increased linearly with increase in number of affected family members.

Conclusion

Family
history of CVD is an independent risk factor for premature CHD. The risk of
premature CHD increases linearly with increase in number of affected family
members. Collecting family history beyond parental history of CVD is important
for risk stratification. Targeting young individuals with family history of CVD
for intensive risk reduction interventions may help to prevent future events.