BACKGROUNDCardiac, pulmonary, and intensive care unit (ICU) rehabilitation/recovery programs are health promotion interventions designed to improve physical recovery, psychological well-being, and quality of life after acute illness while reducing the risk of adverse events.OBJECTIVEIdentify the difference in attendance rates for patients invited to a cardiac rehabilitation, pulmonary rehabilitation, or ICU recovery program and factors influencing attendance.METHODSWe conducted a systematic review and meta-analysis by searching PubMed, EMBASE, CINAHL, Web of Science, and manual reference lists from inception to June 3, 2024. We included studies reporting patient attendance rates in eligible programs following acute illness hospitalization. Two team members independently screened articles and extracted data, with a third member reviewing and achieving consensus when necessary. Our main outcomes focused on the proportion of attendance in eligible programs among patients referred.RESULTSOf 3,446 studies screened, 179 studies (N = 4,779,012 patients) were included across cardiac rehabilitation (n = 153 studies), pulmonary rehabilitation (n = 11 studies), and ICU recovery (n = 15 studies) programs. Pooled attendance rates were 53 % (95 % CI: 48-57 %) for cardiac rehabilitation, 56 % (95 % CI: 42-70 %) for pulmonary rehabilitation, and 61 % (95 % CI: 51-70 %) for ICU recovery programs. Significant attendance heterogeneity was present (cardiac I2=100 %, p < 0.001; pulmonary I2=100 %, p < 0.001; ICU I2=94 %, p < 0.01). Barriers to attendance included transportation, distance, work conflicts, and patient factors (e.g., comorbidities, older age). Facilitators included male gender, younger age, higher education, income, provider recommendations, and flexible scheduling. Individual factors represented the primary domain affecting attendance.CONCLUSIONSThe results indicate comparable attendance rates and factors shaping attendance across acute illness rehabilitation/recovery programs, with ICU recovery programs being the most well-attended on average.REGISTRATIONPROSPERO CRD42022357261.