Identifying patients with Familial Hypercholesterolaemia and evaluating management.
Dr Raj Tanday and Peter Winocour
Welwyn Garden City
Familial hypercholesterolaemia (FH) is a severe form of hyperlipidaemia resulting in early coronary heart disease (CHD). It is caused by a mutation in the genes coding for the LDL receptor. It has autosomal dominant inheritance with a prevalence of 1 in 500.
Given this prevalence we would expect 1000 cases in our local catchment area of East & North Hertfordshire. Far fewer cases are know about. We tried to find out where potential cases were and assess the management of all cases in primary and secondary care.
Retrospective study using lists from medical departments of the trust gave us 42 known cases under secondary care. Taking a laboratory spreadsheet of the highest cholesterol levels from requested blood tests between Jan 2009 and Dec 2009, the top 200 cholesterol levels were taken. Excluded were those with mixed dyslipidaemias. These patients were all found to be in primary care and 52 practices identified. Permission for visiting and case note reviewing only granted from 17 practices. Evaluation of management of all patients was based upon a modified version of the RCP audit proforma for FH.
From primary care 65 patients found with fitting lipid profile but 49 % of cases identified had insufficient data to make a diagnosis. Modal age group 51-70 yrs. Mostly female (71%), mostly white (15%) but ethnicity poorly recorded, mostly non smoking (62%), lifestyle advice given in most (75%), mostly treated with statin alone (58%) but other combinations were used, good evidence of treatment efficacy in secondary care ( 52% reduction in total cholesterol from baseline), majority not had cardiology testing for CHD (60%) and cascade testing done in a majority (60%).
It appears that patients who we suspect to have FH on biochemistry are not being assessed thoroughly to make a diagnosis of the condition - family history of premature cardiovascular disease/hypercholesterolemia and assessment for stigmata not done. Management appears to be good otherwise with evidence of efficacy with treatment and progress with screening relatives.