Background: A premature myocardial infarction (PMI) is usually associated with a familial component. This study evaluated cardiovascular risk factors in first-degree relatives (FDR) of patients with PMI not presenting the familial hypercholesterolemia phenotype.
Methods: A cross-sectional study comprising FDR of non-familial hypercholesterolemia patients who suffered a myocardial infarction <45-years age matched for age and sex with individuals without family history of cardiovascular disease. Subjects were evaluated for presence of the metabolic syndrome and its components, lifestyle, statin therapy, and laboratory parameters.
Results: The sample was composed of 166 FDR of 103 PMI patients and 111 controls. The prevalence of smoking (29.5 vs. 6.3%; p < 0.001), prediabetes (40.4 vs. 27%; p < 0.001), diabetes (19.9 vs. 1.8%; p < 0.001), metabolic syndrome (64.7 vs. 36%; p < 0.001), and dyslipidemia (84.2 vs. 31.2%; p = 0.001) was greater in FDR. There was no difference on the prevalence of abdominal obesity between groups. In addition, FDR presented higher triglycerides (179.0 ± 71.0 vs. 140.0 ± 74.0 mg/dL; p = 0.002), LDL-cholesterol (122.0 ± 36.0 vs. 113.0 ± 35 mg/dL; p = 0.031), non-HDL-cholesterol (157.0 ± 53.0 vs. 141.0 ± 41.0 mg/dL; p = 0.004), and lower HDL-cholesterol (39.0 ± 10.0 vs. 48.0 ± 14.0 mg/dL; p < 0.001) than controls. Thyrotropin levels (2.4 ± 1.6 vs. 1.9 ± 1.0 mUI/L; p = 0.002) were higher in FDR. The risk factor pattern was like the one of index cases. Only 5.9% (n = 10) of FDR were in use of statins.
Conclusions: FDR of non-familial hypercholesterolemia patients with PMI presented an elevated prevalence of metabolic abnormalities, inadequate lifestyle and were undertreated for dyslipidemia.
Keywords: Dyslipidemia; Family history; Metabolic syndrome; Myocardial infarction; Risk factors; Thyroid hormones/metabolism.