Background Pleural infection remains an important cause of mortality. This study aimed to investigate worldwide patterns of pre-existing comorbidities and clinical outcomes of patients with pleural infection. Methods Studies reporting on adults with pleural infection between 2000-2017 were identified from a search of Embase and Medline. Papers reporting exclusively on tuberculous, fungal or post pneumonectomy infection were excluded. Two reviewers assessed 20980 records for eligibility. Results 211 studies met the inclusion criteria. 134 papers (227,898 patients, mean age 52.8 years) reported comorbidity and/or outcome data. The majority of studies were retrospective observational cohorts (n=104, 78%) and the most common region of reporting was East Asia (n=33, 24%) followed by North America (n=27, 20%). 85 papers (50,756 patients) reported comorbidity. The median percentage prevalence of any comorbidity was 72% (IQR 58-83%), with respiratory illness (20%, 16-32%) and cardiac illness (19%, 15-27%) most commonly reported. 125 papers (192,298 patients) reported outcome data. The median length of stay was 19 days (IQR 13-27) and median in-hospital or 30-day mortality was 4% (IQR 1-11%). In regions with high-income economies (n=100, 74%) patients were older (mean 56.5 vs. 42.5 years, p<0.0001), but there were no significant differences in prevalence of pre-existing comorbidity nor in length of hospital stay or mortality. Conclusion Patients with pleural infection have high levels of comorbidity and long hospital stays. Most reported data are from high-income economy settings. Data from lower-income regions is needed to better understand regional trends and enable optimal resource provision going forward.