Background Coronavirus disease 2019(COVID-19)can involve persistence,sequelae,and other clinical complications that last weeks to months to evolve into long COVID-19.Exploratory studies have suggested that interleukin...Background Coronavirus disease 2019(COVID-19)can involve persistence,sequelae,and other clinical complications that last weeks to months to evolve into long COVID-19.Exploratory studies have suggested that interleukin-6(IL-6)is related to COVID-19;however,the correlation between IL-6 and long COVID-19 is unknown.We designed a systematic review and meta-analysis to assess the relationship between IL-6 levels and long COVID-19.Methods Databases were systematically searched for articles with data on long COVID-19 and IL-6 levels published before September 2022.A total of 22 published studies were eligible for inclusion following the PRISMA guidelines.Analysis of data was undertaken by using Cochran's Q test and the Higgins I-squared(I2)statistic for heterogeneity.Random-effect meta-analyses were conducted to pool the IL-6 levels of long COVID-19 patients and to compare the differences in IL-6 levels among the long COVID-19,healthy,non-postacute sequelae of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection(non-PASC),and acute COVID-19 populations.The funnel plot and Egger's test were used to assess potential publication bias.Sensitivity analysis was used to test the stability of the results.Results An increase in IL-6 levels was observed after SARS-CoV-2 infection.The pooled estimate of IL-6 revealed a mean value of 20.92 pg/ml(95%CI=9.30–32.54 pg/ml,I2=100%,P<0.01)for long COVID-19 patients.The forest plot showed high levels of IL-6 for long COVID-19 compared with healthy controls(mean difference=9.75 pg/ml,95%CI=5.75–13.75 pg/ml,I2=100%,P<0.00001)and PASC category(mean difference=3.32 pg/ml,95%CI=0.22–6.42 pg/ml,I2=88%,P=0.04).The symmetry of the funnel plots was not obvious,and Egger’s test showed that there was no significant small study effect in all groups.Conclusions This study showed that increased IL-6 correlates with long COVID-19.Such an informative revelation suggests IL-6 as a basic determinant to predict long COVID-19 or at least inform on the“early stage”of long COVID-19.展开更多
文摘Background Coronavirus disease 2019(COVID-19)can involve persistence,sequelae,and other clinical complications that last weeks to months to evolve into long COVID-19.Exploratory studies have suggested that interleukin-6(IL-6)is related to COVID-19;however,the correlation between IL-6 and long COVID-19 is unknown.We designed a systematic review and meta-analysis to assess the relationship between IL-6 levels and long COVID-19.Methods Databases were systematically searched for articles with data on long COVID-19 and IL-6 levels published before September 2022.A total of 22 published studies were eligible for inclusion following the PRISMA guidelines.Analysis of data was undertaken by using Cochran's Q test and the Higgins I-squared(I2)statistic for heterogeneity.Random-effect meta-analyses were conducted to pool the IL-6 levels of long COVID-19 patients and to compare the differences in IL-6 levels among the long COVID-19,healthy,non-postacute sequelae of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection(non-PASC),and acute COVID-19 populations.The funnel plot and Egger's test were used to assess potential publication bias.Sensitivity analysis was used to test the stability of the results.Results An increase in IL-6 levels was observed after SARS-CoV-2 infection.The pooled estimate of IL-6 revealed a mean value of 20.92 pg/ml(95%CI=9.30–32.54 pg/ml,I2=100%,P<0.01)for long COVID-19 patients.The forest plot showed high levels of IL-6 for long COVID-19 compared with healthy controls(mean difference=9.75 pg/ml,95%CI=5.75–13.75 pg/ml,I2=100%,P<0.00001)and PASC category(mean difference=3.32 pg/ml,95%CI=0.22–6.42 pg/ml,I2=88%,P=0.04).The symmetry of the funnel plots was not obvious,and Egger’s test showed that there was no significant small study effect in all groups.Conclusions This study showed that increased IL-6 correlates with long COVID-19.Such an informative revelation suggests IL-6 as a basic determinant to predict long COVID-19 or at least inform on the“early stage”of long COVID-19.
