Predicting Cardiovascular Events in Familial Hypercholesterolemia: The SAFEHEART Registry (Spanish Familial Hypercholesterolemia Cohort Study)

BACKGROUND

Although risk factors for atherosclerotic cardiovascular disease (ASCVD) in familial hypercholesterolemia (FH) have been described, models for predicting incident ASCVD have not been reported. Our aim was to use the SAFEHEART registry (Spanish Familial Hypercholesterolemia Cohort Study) to define key risk factors for predicting incident ASCVD in patients with FH.

METHODS

SAFEHEART is a multicenter, nationwide, long-term prospective cohort study of a molecularly defined population with FH with or without previous ASCVD. Analyses to define risk factors and to build a risk prediction equation were developed, and the risk prediction equation was tested for its ability to discriminate patients who experience incident ASCVD from those who did not over time.

RESULTS

We recruited 2404 adult patients with FH who were followed up for a mean of 5.5 years (SD, 3.2 years), during which 12 (0.5%) and 122 (5.1%) suffered fatal and nonfatal incident ASCVD, respectively. Age, male sex, history of previous ASCVD, high blood pressure, increased body mass index, active smoking, and low-density lipoprotein cholesterol and lipoprotein(a) levels were independent predictors of incident ASCVD from which a risk equation with a Harrell C index of 0.85 was derived. The bootstrap resampling (100 randomized samples) of the original set for internal validation showed a degree of overoptimism of 0.003. Individual risk was estimated for each person without an established diagnosis of ASCVD before enrollment in the registry by use of the SAFEHEART risk equation, the modified Framingham risk equation, and the American College of Cardiology/American Heart Association ASCVD Pooled Cohort Risk Equations. The Harrell C index for these models was 0.81, 0.78, and 0.8, respectively, and differences between the SAFEHEART risk equation and the other 2 were significant (P=0.023 and P=0.045).

CONCLUSIONS

The risk of incident ASCVD may be estimated in patients with FH with simple clinical predictors. This finding may improve risk stratification and could be used to guide therapy in patients with FH.

CLINICAL TRIAL REGISTRATION

URL: http://clinicaltrials.gov. Unique identifier: NCT02693548.

Coronary Heart Disease, Peripheral Arterial Disease, and Stroke in Familial Hypercholesterolaemia

Objective—

Heterozygous familial hypercholesterolemia (FH) is the most common premature atherosclerotic cardiovascular disease (ASCVD)–related monogenic disorder, and it is associated with ischemic heart disease. There is limited information whether FH increases the risk of peripheral arterial and cerebrovascular disease. Our aim was to analyze ASCVD prevalence and characteristics in different arterial territories in a large FH population, to compare them with an unaffected control population and to determine which factors are associated to ASCVD.

Approach and Results—

SAFEHEART (Spanish Familial Hypercholesterolaemia Cohort Study) is an ongoing registry of molecularly defined patients with heterozygous FH in Spain. ASCVD in the different arterial territories was analyzed, as well as individual characteristics, genetic variables, and lipid-lowering therapies. The study recruited 4132 subjects (3745 ≥18 years); 2,752 of those enrolled were molecularly diagnosed FH cases. Median age was 44.0 years (45.9% men) and 40 years (46.6% men) in FH patients and unaffected relatives ( P <0.001). ASCVD was present in 358 (13.0%) and 47 (4.7%) FH patients and unaffected relatives, respectively ( P <0.001). History of premature ASCVD was more prevalent in FH patients (9.4% and 2.4% in FH patients and unaffected relatives, respectively; P <0.001). Coronary artery–related manifestations and peripheral artery disease were more prevalent in FH patients than in controls, but no significant differences were found for cerebrovascular events. Age, body mass index, type 2 diabetes mellitus, high blood pressure, previous use of tobacco, and lipoprotein(a) >50 mg/dL were independently associated with ASCVD.

Conclusions—

The prevalence of ASCVD is higher, and the involvement of the arterial territories is different in FH patients when compared with their unaffected relatives. Age, male sex, increased body mass index, hypertension, type 2 diabetes mellitus, smoking habit, and lipoprotein(a) >50 mg/dL were independently associated to ASCVD.

Clinical Trial Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT02693548.

Statins do not increase the risk of developing type 2 diabetes in familial hypercholesterolemia: The SAFEHEART study

BACKGROUND

Familial Hypercholesterolemia (FH) is the most common monogenic disorder that causes premature coronary artery disease (CAD). Our objective was to examine the risk of new onset type 2 diabetes mellitus (T2DM) among FH patients and unaffected relatives in relation to treatment with different statins in the SAFEHEART cohort study.

METHODS

This is a cross-sectional and prospective cohort study in 2558 FH and 1265 unaffected relatives with a mean follow-up of 5.9 years. Several pertinent data, such as age, gender, metabolic syndrome, lipid profile, body mass index (BMI), waist circumference, HOMA-IR, dose, duration and type of statins, were obtained and examined as predictors of incident diabetes.

RESULTS

The new onset diabetes was 1.7% in FH and 0.2% in non FH patients (p=0.001). In multivariate logistic regression, age (OR 1.02, CI 95%: 1.02-1.08), HOMA-IR (OR 1.17, CI 95%: 1.03-1.33), metabolic syndrome (OR 3.3, CI 95%: 1.32-8.28) and specifically plasma glucose, as a component of metabolic syndrome (OR 15.7, CI 95%: 4.70-52.53) were significant predictors of new onset T2DM in the FH group alone. In the adjusted Cox regression model in FH group, age (HR 1.03, CI 95% 1.00-1.06, p=0.031) and metabolic syndrome (HR 4.16, CI 95% 1.58-10.92, p=0.004) remained significant predictors of new onset T2DM.

CONCLUSIONS

Our data do not support the postulated diabetogenic effect associated with high-dose statins use in our cohort of FH patients.

[Toxic myopathies related to the administration of hypolipidemic agents: are the drugs the only things responsible?]

The characteristics are reported of five myopathies initially considered toxic in nature caused by the administration of blood lipid lowering agents. In three cases the final diagnosis was hypothyroidism, thus demonstrating the need to rule out the potential causes of secondary dyslipidemia before initiating therapy. Likewise, and because of the rare true muscle involvement from blood lipid lowering agents, it is necessary to investigate those diseases or factors enhancing muscle toxicity when it appears.