Effect of Statins on the Blood Lipid Profile in Patients with Different Cardiovascular Diseases: A Systematic Review with Meta-analysis of Randomized Clinical Trials

Background: Statins are the main lipid-lowering drugs and are used in the prevention of cardiovascular diseases (CVDs). Since the results have been, to some extent, inconsistent in the clinical trials concerning different types of CVDs, a systematic review and meta-analysis was performed to prove the effect of statins on decreasing elevated levels of total cholesterol, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in patients with CVDs. Methods: Literature search was performed on major electronic databases (MEDLINE/ PubMed, Scopus, and ISI Web of Science) from inception up to July 2021 to find randomized controlled trials (RCTs) evaluating the effect of different statins on different types of CVDs. The effect size was determined using weighted mean difference (WMD) and corresponding 95% confidence interval (CI). Results: Statin therapy significantly decreased levels of total cholesterol (WMD = -33.37 mg/dl, 95% CI: -45.98 to -20.76, P<0.001), LDL-C (WMD = -29.42 mg/dl, 95% CI: -36.81 to -22.03, P<0.001), and TG (WMD = -15.19 mg/dl, 95% CI = -26.41 to -3.97, P<0.001), and increased levels of HDL-C (WMD = 1.55 mg/dl, 95% CI: 0.20, to 2.90, P=0.02) in patients with different CVDs. Conclusion: Statin therapy was found effective in lowering levels of total cholesterol, LDL-C, and TG, and increasing levels of HDL-C in patients with different CVDs.