We searched databases including Medline, Embase, Cochrane Library and Web of Science for articles by the end of 30 September 2022. Publications in any language were considered. We used the following items as keywords: (‘angiotensin converting enzyme inhibitor’ OR ‘angiotensin receptor blocker’ OR ‘renin angiotensin system’) AND (‘chronic obstructive pulmonary disease’ OR ‘COPD’ OR ‘chronic obstructive lung disease’, ‘emphysema’). Please see the details in online supplemental material 1.