Beyond Frailty: The Prognostic Value of comorbidity in Non-invasive Ventilation Outcomes

Introduction: Several studies explored the role of frailty in predicting outcomes in critically ill patients. Frailty has been identified as an independent risk factor for all cause morbidity poor outcomes, including mortality, longer hospital stays and complications Rockwood et al. (2005). Muscedere et al. (2017) found that frailty is associated with worse outcomes in patients receiving mechanical ventilation, however there is limited focus on NIV. While NIV is widely used for managing acute respiratory failure, its effectiveness across varying levels of frailty and comorbidity remains unclear. This analysis aims to identify key predictors of mortality, focusing on age, the Clinical Frailty Scale (CFS), and the Charlson Comorbidity Score (CCS).

Methods: A retrospective cohort analysis was carried out over six months was conducted, including patients with a median age of 78 years. Associations were explored between age, CFS, CCS, and outcomes at 7, 30, and 90 days post-NIV. A logistic regression model evaluated predictors of 90-day mortality.

Results: Age was positively associated with both CFS and CCS but showed no significant relationship with NIV duration or short-term outcomes (7- and 30-day mortality). However, age and CFS were significantly associated with 90-day mortality (p < 0.05). CCS was the strongest predictor of mortality, with CCS 5–6 associated with 2.54 times increased odds of 90-day mortality (p = 0.0145), and CCS ≥7 with 4.89 times increased odds (p = 0.0004), compared to CCS 1–4. Neither age, CFS, nor NIV duration remained significant in the multivariable model. Survival probability by day 90 was below 30% for patients with CCS ≥7

Conclusion: The CCS is a robust predictor of 90-day mortality in patients receiving NIV, surpassing age, frailty, and NIV duration. These findings emphasize the need for comorbidity burden assessment in prognostication and care planning rather than age or frailty alone.