Prevalence and impact of psychiatric and neurocognitive comorbidities on pulmonary rehabilitation outcomes

Background Chronic respiratory diseases are associated with psychiatric/neurocognitive comorbidities; prevalence, clinical impact and responsiveness to in-patient pulmonary rehabilitation (PR) remain poorly characterized. Aims To assess prevalence of psychiatric and neurocognitive comorbidities in patients admitted to a PR programme, their associations with clinical and rehabilitation outcomes, and to explore sex- and age-related differences. Methods In this multicentre-observational-prospective-cohort study, consecutive admitted to in-patient PR programmes over 12 months were classified into six groups: diagnosed psychiatric disorders, psychotropic drug use without diagnosis, respiratory disease only, diagnosed neurocognitive disorders, psychiatric/cognitive impairment detected during hospitalisation and referral for diagnostic assessment. Clinical, functional and psychological data were collected at admission and discharge. Outcomes included changes in and achievement of minimal clinically important differences (MCIDs) for CAT, MRC dyspnea scale, Barthel Dyspnea Index and Six-Minute Walki Test. A composite responder outcome required achievement of all MCIDs. Multivariable logistic regression identified predictors of response. Results Among 975 patients (59% males, 70.2 years old), 49% had psychiatric (N = 245) and/or neurocognitive comorbidities (N = 45). Psychiatric disorders were more frequent in women, while cognitive impairment increased with age. PR significantly improved outcomes across all groups; however, patients with cognitive impairment showed the poorest multidimensional response, with none achieving the composite endpoint. In a relatively small group (N = 395) a formal psychiatric diagnosis independently predicted a lower probability of response. Conclusion Psychiatric and neurocognitive comorbidities are highly prevalent in inpatient PR. Although PR is effective overall, cognitive impairment markedly limits multidimensional benefit, highlighting need for routine mental health, cognitive screening and multidisciplinary care.