Hypercholesterolemia, eligibility for lipid-lowering therapy and therapeutic success: Population-based study in a Portuguese urban population

Abstract

Background: We aimed to estimate i) the prevalence of hypercholesterolemia, ii) the proportion of individuals eligible for treatment with lipid-lowering drugs, and iii) therapeutic success, according to the European guidelines on cardiovascular disease prevention in clinical practice. Design: Population-based cross-sectional study. Methods: We surveyed a representative sample of the population of Porto aged 40-65 years. Trained interviewers collected data from 1215 subjects (789 women) on demographic variables, medical history, and medication using structured questionnaires. A fasting venous blood sample was withdrawn. Subjects were considered low risk or high risk as indicated in the European guidelines. Hypercholesterolemia was defined as total cholesterol (TC) ≥ 5 mmol/l or low-density-cholesterol (LDL-C) ≥ 3 mmol/l in low-risk subjects, TC ≥ 4.5 mmol/l or LDL-C ≥ 2.5 mmol/l in high-risk subjects or being medicated with lipid-lowering drugs. Eligibility for treatment was defined as being high risk and having TC ≥ 4.5 mmol/l, LDL-C < 2.5 mmol/l or being on treatment. We defined therapeutic success as having TC < 4.5 mmol/l and LDL-C < 2.5 mmol/ l among medicated subjects. Results: Overall, 84.9% (95% confidence interval (95% CI): 82.7-86.8) of subjects had hypercholesterolemia and 9.1% (95% CI: 7.5-10.8) were medicated with lipid-lowering drugs. Men were more likely to be eligible for treatment (42.4%) than women (22.4%; OR= 2.69, 95% CI 2.07-3.52). Therapeutic success was less frequent in men (46.8%) than in women (66.7%), (OR=0.39, 95 % CI 0.17-0.87). Conclusion: Strict interpretation of the European guidelines would label 85% of the general population in this age group as hypercholesterolemic and a third eligible for drug treatment. Questions arise regarding medicalization, resource allocation, and sustainability within the healthcare system. © 2008 European Society of Endocrinology.