Standards of care and clinical predictors in patients hospitalised for a COPD exacerbation - The Italian SOS (Stratification Observational Study)

Background and aims. Hospitalisations for chronic obstructive pulmonary disease (COPD) exacerbations are major events in the natural history of the disease in terms of survival, quality of life and risk of further episodes of exacerbation. The aims of study were to evaluate: 1. adherence to recommended standards of care; and 2. clinical factors influencing major outcomes during hospitalisation for an episode of COPD exacerbation and within a 6-month follow-up. Methods. An observational, prospective study was conducted in 68 centres. Assessment of standards of care included diagnostic procedures (such as pulmonary function tests and microbiology) and management options (such as drug therapies, vaccinations and rehabilitation). Outcome measures relevant to the hospitalisation were: survival, need for mechanical ventilation, and length of stay (LOS). Outcomes at 6-months were: survival, exacerbations and hospitalisations for an exacerbation. Multivariate logistic regression was applied to evaluate the relation between clinical factors and outcomes. Results. 931 patients were enrolled. Only 556 patients (59.7%) were diagnosed COPD and stratified for severity with the support of spirometry (FEV1/VC ≤0.7) and were considered for outcome analysis. Among treatments, pulmonary rehabilitation and anti-smoking counselling were applied infrequently (14.5 and 8.1% of patients, respectively). Within six months 63 COPD patients (17.7%) had at least one episode of exacerbation prompting a further hospitalisation and 19 died (5.3%). Predictor of mortality was the co-morbidity Charlson index (odds ratio, OR 10.3, p=0.03 CI:1.25-84.96). A further hospitalisation was predicted by hospitalisation for an exacerbation in the previous 12 months (OR 3.59, p=0.003 CI:1.54-8.39). Conclusions. Standards of care were far lower than recommended, in particular 40% of patients were labelled as COPD without spirometry. COPD patients with a second hospitalisation in 12 months for an exacerbation had about 3 times the risk of suffering a new episode and hospitalisation in the following six months.