Does long-term oxygen therapy reduce hospitalisation in hypoxaemic chronic obstructive pulmonary disease?

The aim of this study was to determine whether long-term oxygen therapy (LTOT) reduces hospitalisation in hypoxaemic patients with chronic obstructive pulmonary disease (COPD). The circumstances of initiation of LTOT (start during hospitalisation versus start as an outpatient) and compliance with oxygen were also investigated (continuous oxygen therapy (COT) > or = 15 h daily versus noncontinuous oxygen therapy (NCOT) <15 h daily). A total 246 COPD patients were studied, with each patient acting as their own control. Patients were divided into four groups: 125 patients on COT who started LTOT in conjunction with hospitalisation, 37 patients on COT who started LTOT as outpatients, 58 patients on NCOT who started LTOT in conjunction with hospitalisation and 26 patients on NCOT who started LTOT as outpatients. Admission rates, days spent in hospital and number of patients with at least one hospitalisation (ever hospitalised) were compared in two periods of 10 months before and after initiation of LTOT. Overall during the LTOT period, in comparison with the preoxygen period, the admission rates, hospital days and "ever hospitalised" were reduced by 23.8%, 43.5% and 31.2%, respectively. Among patients who started LTOT as outpatients, a tendency towards a higher effect in the compliant group was observed. This study shows that in hypoxaemic chronic obstructive pulmonary disease patients, long-term oxygen therapy is associated with a reduction in hospitalisation.