Multiple factors help predict risk for patients with FH

PHILADELPHIA — LDL is not the sole predictor of CVD in the familial hypercholesterolemia patient population, according to a presentation at the National Lipid Association Scientific Session.

Alexis Baass, MD, MSc, FRCPC, DABCL, assistant professor in the department of medicine at Royal Victoria Hospital in Quebec, presented the Montreal-FH-SCORE, a system designed to identify CVD risk beyond LDL levels in patients with familial hypercholesterolemia (FH).

For the development cohort, Baass and colleagues used a retrospective cohort of 670 adults with confirmed FH. CVD events were defined as coronary peripheral and cerebrovascular events and lipid profiles were collected at baseline without lipid-lowering medication. The goal was to identify the strongest independent predictors for CVD and develop a practical risk-scoring tool based on it.

For the validation cohort, the researchers used 718 adults with confirmed FH from the ECOGENE-21 Clinical Research Center FH database. CVD events were defined as coronary and cerebrovascular events and untreated baseline LDL was collected without lipid lowering medication (n=624) or calculated via a validated equation (n=94). The goal was to confirm the utility of the score based on findings from the development cohort.

A multivariable model derived from the development cohort showed that only five variables were associated with CV risk factors, Baass and colleagues found. The largest predictor in this development cohort was age (β-coefficient = .75; P <.0001), HDL (β = -.27; P < .0001), gender (β = .25; P < .0001), hypertension (β = .19; P = .0003) and smoking (β = .12; P = .04).

According to Baass, the coefficient scores and the distribution of variables were used to create a score system similar to primary risk scores. The Montreal-FH-SCORE was calculated using these variables and compared to individual variables.

The results of the study show that there is a better predictive capacity using the Montreal-FH-SCORE (area under the curve [AUC]= 0.84) than with individual variables, such as age (AUC = 0.793), gender (AUC = 0.585) or HDL (AUC = 0.616).

According to the median of the Montreal-FH-SCORE, patients in the development cohort with a high score are tenfold more likely to have CV events than low-scoring patients (OR = 10.3).

Similar results were obtained in the validation cohort, in which the score had an AUC of 0.799 and those with a high score were more than eightfold more likely to have CV events than those with a low score (OR = 8.8).

The two cohorts were combined to include 1,388 genetically confirmed FH patients in an attempt to identify further variables that could help in the stratification of risk in this population. In the combined results, lipoprotein(a) was also an independent predictor of CV events (β = .11; P = .02).

When the combined cohort score was compared with the Montreal-FH-SCORE alone, there was a slightly better predictability, but the difference in AUC was not significant, Baass said.

“In conclusion, age, HDL, gender, smoking [and] hypertension can be combined to perhaps better stratify risk in FH patients,” she said.

The abstract won first place in the Oral Abstract Competition. – by Dave Quaile

Reference:

Baass A, et al. Abstract 115. Presented at: National Lipid Association Scientific Sessions; May 18-21, 2017; Philadelphia.

Disclosure: Baass reports financial ties with various device and pharmaceutical companies.