The risk of burn injury during long-term oxygen therapy: a 17-year longitudinal national study in Sweden

BACKGROUND: Long-term oxygen therapy (LTOT) improves the survival time in hypoxemic chronic obstructive pulmonary disease. Despite warnings about potential dangers, a considerable number of patients continue to smoke while on LTOT. The incidence of burn injuries related to LTOT is unknown. The aim of this study was to estimate the rate of burn injury requiring health care contact during LTOT. METHODS: Prospective, population-based, consecutive cohort study of people starting LTOT from any cause between January 1, 1992 and December 31, 2009 in the Swedish National Register of Respiratory Failure (Swedevox). RESULTS: In total, 12,497 patients (53% women) were included. The mean (standard deviation) age was 72±9 years. The main reasons for starting LTOT were chronic obstructive pulmonary disease (75%) and pulmonary fibrosis (15%). Only 269 (2%) were active smokers when LTOT was initiated. The median follow-up time to event was 1.5 years (interquartile range, 0.55–3.1). In total, 17 patients had a diagnosed burn injury during 27,890 person-years of LTOT. The rate of burn injury was 61 (95% confidence interval, 36–98) per 100,000 person-years. There was no statistically significant difference in the rate of burn injury between ever-smokers and never-smokers, or between men and women. CONCLUSION: The rate of burn injuries in patients on LTOT seems to be low in Sweden. The strict requirements in Sweden for smoking cessation before LTOT initiation may contribute to this finding.