Population attributable fraction estimates of cardiovascular diseases in different levels of plasma total cholesterol in a large-scale cross-sectional study: a focus on prevention strategies and treatment coverage

Purpose: Cardiovascular diseases (CVDs) are the main cause of deaths among non-communicable diseases. Arguments about the best prevention strategy to control CVDs' risk factors continue. We evaluated the population attributable fraction (PAF) of CVDs in different levels of plasma cholesterol.

Methods: Patients' data were obtained from Iran STEPs 2016 study. In phase 0 we estimated PAF regardless of cholesterol levels and clinical factors. In phase 1 we calculated PAF based on three levels of cholesterol (<200, 200-240, ≥240 mg/dl). In phase 2 we estimated PAF in 3 groups considering lipid-lowering drugs. In phase 3 all treated participants and not treated hypercholesterolemic people were included, to evaluate the impact of treatment. Estimations were done for Ischemic heart disease (IHD) and ischemic stroke (IS), and for two sex.

Results: In phase 0, the highest PAF for IHD and IS were 0.35 (95% confidence interval 0.29-0.41) and 0.22 (0.18-0.27) for females and 0.27 (0.22-0.32) and 0.18 (0.14-0.22) for males. In phase 1, the highest PAF belonged to population with cholesterol ≥240 mg/dl and IHD, as 0.90 (0.85-0.94) for females, and 0.90 (0.85-0.96) for males. In phase 2, the pre-hypercholesterolemic group had higher PAFs than the hypercholesteremic group in most of the population. Phase 3 showed treatment coverage significantly lowered fractions in all age groups, for both causes.

Conclusion: An urgent action plan and a change in preventive programs of health guidelines are needed to stop the vast burden of hypercholesterolemia in the pre-hypercholesterolemic population. Population-based prevention strategies need to be more considered to control further CVDs.

Supplementary information: The online version contains supplementary material available at 10.1007/s40200-020-00673-3.