TNF and chronic obstructive pulmonary disease: Atorvastatin substantially decreased TNF-α (WMD: − 0.20 pg/mL; 95% CI − 0.28 to − 0.11), LDL cholesterol (WMD: − 21.48 mg/dL; 95% CI − 30.82 to − 12.14), and TC (WMD: − 15.24 mg/dL; 95% CI − 28.28 to − 2.20), while improving 6MWD (WMD: 0.71; 95% CI 0.24 to 1.17) and FEF25-75 in COPD subgroups.