Family history of hypertension: A novel and potent risk factor for premature coronary artery disease

Background. While high blood pressure is strongly associated with an increased risk of coronary artery disease (CAD), the contribution of a parental history of hypertension to prevalence of CAD remains unclear. Aim. The aim of this study was to test the hypothesis that a positive family history of hypertension is independently linked to an increased risk of CAD in a large cohort of young (<40 years), middle-aged (40-60 years) and elderly (>60 years) subjects participating in the Polish Hypertension Survey. Methods. We studied 310 579 subjects (176 908 females and 133 671 males; mean age 46±17 years, mean BMI 25.3±4.4 kg/m²). Hypertension was defined as SBP >140 mmHg and/or DBP >90 mmHg, or taking antihypertensive treatment. Results. Parental hypertension was strongly and independently linked to increased risk of CAD in all age groups. Compared to subjects with a negative family history of hypertension, and after adjusting for blood pressure, the odds ratio for CAD in subjects with positive family history was 2.25 (95% confidence interval 2.11 to 2.39) for young subjects, 1.53 (1.48 to 1.58) for middle aged subjects and 1.62 (1.51 to 1.73) for elderly subjects. This blood pressure independent interaction between family history of hypertension and the prevalence of CAD was also strikingly evident when normotensive subjects were analyzed separately. Odds ratio for CAD in normotensives was 2.23 (2.40 to 2.06), 1.40 (1.33 to 1.47) and 1.32 (1.26 to 1.38), respectively. Conclusions. Family history of hypertension is associated with increased risk of CAD. This association is independent of age and blood pressure level.