ABSTRACT
Purpose of Study Coronavirus disease (COVID-19) can range from asymptomatic infection to severe illness with multiorgan failure. Recent studies demonstrated an association between lower serum lipid levels namely high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC) and COVID-19 disease severity. But the results lack consistency, and the magnitude of the association is currently unknown. Methods Used We conducted a systematic review and metaanalysis on the difference in HDL, LDL, TC, and triglycerides (TG) levels between 1) COVID-19 patients and healthy controls 2) COVID-19 patients with and without severe disease 3) COVID-19 patients who died and who survived. We included articles from PubMed and Embase up to September 1, 2021. We analyzed the pooled mean differences (pMD) in lipid levels (mg/dL) for the above-mentioned groups using random effects meta-analysis and assessed publication bias using funnel plots. Summary of Results Among the 441 articles retrieved, 29 articles (26 retrospective and 3 prospective cohorts) met the inclusion criteria with an aggregate of 256,721 participants. Patients with COVID-19 had lower HDL (pMD = -6.95), and TC (pMD = -14.9) levels (table 1 and figure 1). There was no difference in LDL and TG levels among patients with and without COVID-19. Patients with severe COVID-19 had lower HDL (pMD = -4.4), LDL (pMD = -4.4), and TC (pMD = -10.4) levels compared to non-severe COVID-19 patients. Patients who died had lower HDL (pMD = -2.5), LDL (pMD = -10.6) and TC (pMD = -14.9) levels. TG levels did not differ with COVID-19 severity or mortality. None of the above analyses showed statistically significant publication bias. Conclusions Our analysis demonstrated lower lipid levels in COVID-19 patients compared to healthy controls. Among COVID-19 patients, lower HDL, LDL, and TC levels were associated with severity and mortality. We believe that reduced lipoprotein levels are secondary to systemic inflammation and hepatic dysfunction. Lipid levels could be explored as potential prognostic factors in patients with COVID-19. (Table Presented).