Lack of participant diversity in COPD maintenance inhaler clinical trials

<bold>Introduction:</bold> Social determinants of health (SDH; sex, socioeconomic status (SES), ethnicity, occupation and education) play key roles in disease prevalence and progression in chronic obstructive pulmonary disease (COPD) and may impact acceptability or effectiveness of treatments. This review aimed to 1. examine recruitment strategies to target diverse populations in COPD clinical trials of LAMA +/- LABA inhalers, and 2. determine if SDH are reported in primary trial documents or published results. <bold>Methods:</bold> Four clinical trials databases (CENTRAL, Clinicaltrials.gov, ISRCTN and ANZCTR) were searched to identify LAMA +/- LABA clinical trials in adults with COPD between 01/01/2000 and 08/05/2023. Extracted data included: study locations, targeted SDH, recruitment strategies, study outcomes and eligibility criteria. <bold>Results:</bold> Of 1822 trials identified, 491 primary trials were included, 407 of which had results available and 341 had associated publications. Age (n=387 trials, 95.1%) and sex (n=386 trials, 94.8%) were well reported in published results. Of 256,271 participants in published results describing sex, there was a male preponderance (n=176307, 68.8%). 207 (50.9%) trials reported on race, which demonstrated an overrepresentation of white individuals (n=130,086, 83.2%). Only one trial reported either SES or occupation. No trials reported on education or rurality. Trials were mainly conducted in high or upper-middle income countries (95.8%). <bold>Conclusion:</bold> SDH, other than age and sex, were under-reported in LABA/LAMA COPD trials, and when reported, lacked diversity in ethnicity among participants. Future trials must include and report on diverse populations to demonstrate efficacy for all people in all contexts.