Mortality Predictors of COPD Exacerbation Patients in ICU

Abstract

Background: Chronic Obstructive Pulmonary Disease (COPD) is a leading cause of global mortality, with acute exacerbations frequently necessitating intensive care unit (ICU) admissions. Despite its significant burden, data on specific prognostic factors for ICU outcomes in COPD patients particularly in the Indian context remain limited.

Objective: This study aims to identify key clinical, laboratory, and radiological predictors of outcomes in COPD patients admitted to the ICU following acute exacerbations.

Methods: A prospective observational study was conducted from August 2022 to April 2024 at a tertiary centre of eastern India. Patients aged 40 years and above with a confirmed diagnosis of COPD (as per GOLD 2023/24 guidelines) and admitted for acute exacerbation were included. Exclusion criteria encompassed terminal illnesses and advanced organ failure. Data were collected using a predefined proforma with variables of demographic status, clinical findings, laboratory values, and radiological findings. Statistical analysis was performed using SPSS v26, with a p-value <0.05 considered statistically significant.

Results: Among 205 patients enrolled, the mean age was 64.3 ± 11.5 years, with a predominance of males (70%). ICU mortality was significantly higher
in patients aged ≥60 years (p<0.01). Malnutrition, reflected by a BMI <18.5 kg/m² in 45% of patients, was strongly associated with increased mortality
(p<0.01). Most patients belonged to GOLD Group D or E, with Group E showing the highest mortality risk (p<0.01). A history of previous exacerbation within the last year was also linked to worse outcomes (p<0.01).

Elevated inflammatory markers total leukocyte count >11,000/mm³ and high C-reactive protein (CRP) were significantly associated with poor prognosis (p<0.01). While non-invasive ventilation was the most commonly used modality (62%), and invasive ventilation was employed in 18%, no significant difference in mortality was found between ventilation strategies. The duration of ICU stay was notably longer among non-survivors (7.8 vs. 5.2 days; p<0.05).

Interestingly, common comorbidities such as hypertension, diabetes, and coronary artery disease did not independently predict ICU mortality, suggesting the dominance of acute respiratory derangement over chronic health conditions in short-term outcomes.

Conclusion: This study underscores the prognostic significance of advanced age, low BMI, prior exacerbation history, GOLD Group E classification, and systemic inflammatory markers in determining ICU outcomes in COPD patients. Surprisingly, the type of ventilatory support and comorbidities were not significant predictors of short-term mortality. These findings advocate for a more personalized, risk-based approach to ICU care in COPD, emphasizing early identification, nutritional intervention, and inflammatory monitoring.

Clinical Implications: Routine assessment of BMI and inflammatory markers such as CRP and TLC on admission can aid in early risk stratification. Nutritional support and proactive management strategies should be prioritized for high-risk patients. The use of composite indices like the BODE score may offer a more comprehensive prognostic framework than GOLD staging alone.