Family history and premature coronary heart disease

We were interested in studying whether a family history of coronary heart disease (CHD) persisted as a significant risk factor for premature coronary heart disease after adjusting for traditional and nontraditional risk factors.Ninety-five case patients with documented premature CHD (occurring in a person less than 60 years old and with greater than 50 percent occlusion of a major epicardial vessel or a documented myocardial infarction) and 95 community-based control patients were examined for risk factors including family history, hypertension, diabetes mellitus, sedentary lifestyle, smoking, body mass index, total cholesterol, high-density lipoprotein cholesterol, triglycerides, low-density lipoprotein cholesterol, lipoprotein(a), homocysteine, and fibrinogen.The risk of premature CHD for a positive family history ranged from an odds ratio (OR) of 3.25 for a standard family history of CHD in a first-degree relative, 5.9 for family history of early CHD in a first-degree relative before the age of 45 years, and 6.1 for a strong family history of CHD defined as CHD in at least two first-degree relatives. Family history persisted as a significant risk factor for premature CHD (OR = 3.9, 95 percent confidence interval [CI] 1.8-8.7) in multiple variable models that included traditional and nontraditional risk factors. It was rare, however, for a person with a positive family history not to have at least two other traditional or nontraditional risk factors.Family history of CHD should not be considered a simple binary risk factor for premature CHD, and a positive family history of CHD indicates that a person is at high risk for premature CHD independent of traditional and nontraditional risk factors.