Abstract 15749: Sex-differences in Coronary Heart Disease Between Individuals With Familial Hypercholesterolemia and Controls in Norway During 1992-2017

Abstract

Introduction: During the last 30 years, treatment of familial hypercholesterolemia (FH) has been revolutionized, but it is not known if both sexes equally benefit in these advances, and whether this could have affected the sex difference in risk of coronary heart disease (CHD). We aimed to study sex difference in the risk of CHD between men and women with FH compared to non-FH men and women. Methods: We obtained data on CHD hospitalization and death from Norwegian health registries in 4,525 individuals diagnosed with FH between 1992 and 2014 and an age and sex matched control population of 88,892. The sex distribution was about 50/50 between women and men, and the mean age at start of follow-up was 36 years. Results: The cumulative incidence of CHD (FH vs. non-FH controls) in women and men are shown in Figure 1 with a clear increased risk in FH compared to controls. The cumulative incidence starts to increase at a younger age in men compared with women, both in FH and non-FH controls. This corresponds to an age adjusted 2.6-fold higher risk of CHD in men compared with women in both the FH and control population. In the FH population, men aged 20-39 years had a hazard ratio (HR) of 5.3 (95% CI: 2.6-10.9) compared with women, whereas the corresponding HR between women and men in non-FH controls was 3.7 (95% CI: 2.6-5.3). There was no significant interaction between sex and FH status, indicating that the excess risk in men was similar in FH and non-FH controls. Stratified by sex and adjusted for age, we found that both men and women with FH had a 2-fold higher risk of CHD than controls. The highest excess risk was observed in ages 20-30 years with a of HR= 4.5 (95% CI: 2.2-9.2) and a HR of= 5.5 (95%CI: 4.60-9.34) in women and men, respectively. Conclusions: The risk of CHD among individuals with FH was higher in men than in women in all age groups presented, with no differences between the FH sample and the non-FH controls. However, the relative risk in FH compared with controls was similar for both sexes.