Title | Imputation of Baseline LDL Cholesterol Concentration in Patients with Familial Hypercholesterolemia on Statins or Ezetimibe. |
Publication Type | Journal Article |
Year of Publication | 2017 |
Authors | Ruel, I, Aljenedil, S, Sadri, I, de Varennes, É, Hegele, RA, Couture, P, Bergeron, J, Wanneh, E, Baass, A, Dufour, R, Gaudet, D, Brisson, D, Brunham, LR, Francis, GA, Cermakova, L, Brophy, JM, Ryomoto, A, Mancini, GBJ, Genest, J |
Journal | Clinical Chemistry |
Pagination | pii: clinchem.2017.279422 |
Date Published | 10/2017 |
ISSN | Print: 0009-9147; Online: 1530-8561 |
Abstract | BACKGROUND: Familial hypercholesterolemia (FH) is the most frequent genetic disorder seen clinically and is characterized by increased LDL cholesterol (LDL-C) (>95th percentile), family history of increased LDL-C, premature atherosclerotic cardiovascular disease (ASCVD) in the patient or in first-degree relatives, presence of tendinous xanthomas or premature corneal arcus, or presence of a pathogenic mutation in the LDLR, PCSK9, or APOB genes. A diagnosis of FH has important clinical implications with respect to lifelong risk of ASCVD and requirement for intensive pharmacological therapy. The concentration of baseline LDL-C (untreated) is essential for the diagnosis of FH but is often not available because the individual is already on statin therapy. METHODS: To validate a new algorithm to impute baseline LDL-C, we examined 1297 patients. The baseline LDL-C was compared with the imputed baseline obtained within 18 months of the initiation of therapy. We compared the percent reduction in LDL-C on treatment from baseline with the published percent reductions. RESULTS: After eliminating individuals with missing data, nonstandard doses of statins, or medications other than statins or ezetimibe, we provide data on 951 patients. The mean ± SE baseline LDL-C was 243.0 (2.2) mg/dL [6.28 (0.06) mmol/L], and the mean ± SE imputed baseline LDL-C was 244.2 (2.6) mg/dL [6.31 (0.07) mmol/L] (P = 0.48). There was no difference in response according to the patient's sex or in percent reduction between observed and expected for individual doses or types of statin or ezetimibe. CONCLUSIONS: We provide a validated estimation of baseline LDL-C for patients with FH that may help clinicians in making a diagnosis. |
DOI | 10.1373/clinchem.2017.279422 |