C-reactive protein and body mass index predict outcome in end-stage respiratory failure

To determine the predictive factors of morbidity and mortality in patients with end-stage respiratory disease.

Prospective, multicenter cohort study.

Thirteen outpatient chest clinics within the Association Nationale de Traitement à Domicile de l'Insuffisance Respiratoire.

Stable adult patients with chronic respiratory failure receiving long-term oxygen therapy and/or home mechanical ventilation (n = 446; 182 women and 264 men; aged 68.5 +/- 12.1 years [+/- SD]); Respiratory diseases were COPD in 42.8%, restrictive disorders in 36.3%, mixed respiratory failure in 13.5%, and bronchiectasis in 7.4%. Recruitment was performed during the yearly examination. Patients with neuromuscular diseases and sleeping apnea were excluded.

Hospitalization days and survival were recorded during a follow-up of 14.3 +/- 5.6 months. Body mass index (BMI), serum albumin, and transthyretin levels were considered for their predictive value of outcome, together with demographic data, underlying respiratory disease, respiratory function, hemoglobin, C-reactive protein, smoking habits, oral corticosteroid use, and antibiotic treatment courses. Overall, 1.8 +/- 1.7 hospitalizations (cumulative stay, 17.6 +/- 27.1 days) were observed in 254 of 446 patients (57%). Independent predictors of hospitalization were oral corticosteroids, FEV(1), and plasma C-reactive protein. One-year and 2-year cumulative survivals were 93% and 69%, respectively. Plasma C-reactive protein, BMI, Pao(2) on room air, and oral corticosteroids independently predicted survival in multivariate analysis.

Besides established prognosis factors such as FEV(1) and Pao(2), nutritional depletion as assessed by BMI and overall systemic inflammation as estimated by C-reactive protein appear as major determinants of hospitalization and death risks whatever the end-stage respiratory disease. BMI and C-reactive protein should be included in the monitoring of chronic respiratory failure. Oral corticosteroids as maintenance treatment in patients with end-stage respiratory disease are an independent risk factor of death, and should be avoided in most cases.