Journal of Medical Sciences and Health Care Research
Importance of Absolute Low-Density Lipoprotein Cholesterol Reduction: A Systematic Review of 58,778 Participants from 10 Randomized Trials
Abstract
Bishnu Mohan Singh, Hari K. Lamichhane, Narayan Bohara, Faiza Ahmed, Faiza Zakaria, Prabhat Adhikari, Sistu K.C, Binod K.C., Puja Singh, Tripti Sharma, Zouina Sarfraz, Jeevan Gautam, Uzoamaka Nwokorie, Endrit Shahini, Sai Harsha Bobba, Antonino La Spada, Akshay Patel, Sravya Gudapati, Godsgift Enebong Nya and Yasar Sattar
Background: Statins are drugs that lower the level of low-density lipoprotein cholesterol (LDL-C). Statins lower LDL-C in both populations with high and low mean baseline LDL-C concentrations, preventing cardiovascular disease (CVD) and mortality. Hence, it is essential to study the relationship between the amount of decrease in LDL-C level with statins and the prevention of CVD. The central objective of this systematic review is to determine the relationship between the amount of LDL-C reduction with statins and primary prevention of CVD or mortality.
Methods: We identified published articles in electronic databases, including Google Scholar, PubMed, Cochrane Library, and PubMed Central. Two reviewers independently screened the articles via Covidence software, and an assessment of the quality of included studies was done via the Cochrane risk of bias assessment tool. We analyzed the primary endpoint of selected Randomized Clinical Trials (RCTs) in terms of hazard ratio (H.R.) or risk ratio (R.R.). We associated the primary endpoint with the amount of LDL-C reduction achieved in the RCTs. For those RCTs whose primary endpoint was non-clinical, we analyzed the secondary endpoint or other clinical outcomes.
Results: Based on our eligibility criteria, we included ten RCTs in our review. Statistically significant clinical outcomes were associated with the reduction of LDL-C in seven RCTs. In the remaining three RCTs, a significant reduction in LDL-C was achieved, but the clinical outcome was statistically insignificant.
Conclusion: Our systematic review proves an association of the amount of LDL-C reduction with primary prevention of CVD and mortality. Further research is warranted to quantify these associations. Based on current evidence, the amount of LDL-C reduction seems more predictable for reducing cardiovascular events (CVEs) or mortality among populations. Therefore, clinical guidelines on statins should focus on the amount of LDL-C reduction for primary prevention of CVD and mortality rather than baseline LDL-C.