Individuals with familial hypercholesterolemia have increased risk of re-hospitalization after acute myocardial infarction compared with controls

Abstract

Abstract Background and aim We have previously reported that individuals with familial hypercholesterolemia (FH) have a two-fold increased risk of acute myocardial infarction (AMI) compared with the general population. The consequences of having an AMI on re-hospitalization and mortality are however less known. The aim of the present study was to compare the risk of re-hospitalization with AMI and CHD and risk of mortality after incident (first) AMI-hospitalization between persons with and without FH (controls). Methods The original study population comprised 5691 persons diagnosed with FH during 1992–2014 and 119511 age and sex matched controls randomly selected from the general Norwegian population. We identified 221 individuals with FH and 1947 controls with an incident AMI registered in the Norwegian Patient Registry (NPR) or the Cardiovascular Disease in Norway Project during 2001–2017. Persons with incident AMI were followed until December 31st 2017 for re-hospitalization with AMI or coronary heart disease (CHD) registered in the NPR, and for mortality through linkage to the Norwegian Cause of Death Registry. Risk of re-hospitalization was compared with sub-hazard ratios (SHR) from competing risk regression with death as competing event, and mortality was compared using hazard ratios (HR) from Cox regression. All models were adjusted for age. Results Risk of re-hospitalization was 2-fold increased both for AMI [SHR=2.53 (95% CI: 1.88–3.41)] and CHD [SHR=1.82 (95% CI: 1.44–2.28)]. However, persons with FH did not have increased 28-day mortality following an incident AMI (HR=1.05 (95% CI: 0.62–1.78), but the longer-term (>28 days) mortality after first AMI was increased in FH [HR=1.45 (95% CI: 1.07–1.95]. Conclusion This study yields the important finding that persons with FH have increased risk of re-hospitalization of both AMI and CHD after incident AMI. These findings call for more intensive follow-up of individuals with FH after an AMI. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): University of Oslo and Oslo University Hospital