Cardiovascular disease incidence in 21 years follow-up in severe and non-severe familial hypercholesterolaemia (FH) : Data from the UK Simon Broome FH register (2020)

Type of publication:
Conference abstract

Iyen B.; Qureshi N.; Weng S.; Roderick P.; *Capps N.; Durrington P.; Mcdowell I.; Soran H.; Neil A.; Humphries S.E.

Atherosclerosis; December 2020; vol. 315

Background: The Simon Broome (SB) FH register has previously reported a 2.2-fold higher Cardiovascular Disease (CVD) mortality in those with "severe-FH" (SFH) compared to "non-severe-FH" (NSFH). Here we examine CVD morbidity over 21 years follow-up, by linking the register participants with the UK secondary care Hospital Episode Statistics (HES) database.
Method(s): SFH and NSFH were as defined by the 2016 International Atherosclerosis Society criteria. Patients aged 20-79 years (52% female) were recruited from 21 UK lipid clinics and followed between 1997-2018. Outcomes analysed were composite CVD (first HES outcome of coronary heart disease (CHD), myocardial infarction, stable or unstable angina, stroke, TIA, PVD, heart failure, PCI and CABG) and then CVD subtypes. The excess Standardised Morbidity Ratio (SMbR) compared to an age-matched UK general practice sample was calculated (95% Confidence intervals).
Result(s): Of the 3553 SB register subjects, linkage with HES was available for 2988 (84%) participants, of whom 1,646 (66.7%) met the SFH definition. Overall the composite CVD SMbR was 6.55(6.20-6.92). In the SFH group (27,680 pyrs follow-up and 762 events) the SMbR for any CVD event was 9.38 (8.74-10.07), while in the NSFH group (13,750 pyrs follow-up and 237 events) was 5.87(5.17-6.67). For CHD the estimates were 11.88(11.01-12.82) vs 7.38(6.45-8.47) respectively.
Conclusion(s): CVD morbidity in conventionally treated FH patients was over 6-fold higher than the general population, with rates in those with SFH 60% higher than those with NSFH. This emphasises the potential value of more intensive lipid-lowering, and management of other risk factors for those with FH.