Long-term survival in patients hospitalized for chronic obstructive pulmonary disease: a prospective observational study in the Nordic countries

Abstract

Gunnar Gudmundsson,1,2 Charlotte Suppli Ulrik,3 Thorarinn Gislason,1,2 Eva Lindberg,4 Eva Brøndum,3 Per Bakke,5 Christer Janson31Department of Respiratory Medicine, Allergy and Sleep, National University Hospital, Reykjavik, Iceland; 2Faculty of Medicine, University of Iceland, Reykjavik, Iceland; 3Department of Respiratory Diseases, Hvidovre Hospital, University of Copenhagen, Copenhagen, Denmark; 4Department of Medical Sciences: Respiratory Medicine and Allergology, Uppsala University, Uppsala, Sweden; 5Haukeland University Hospital, Bergen, NorwayBackground and aim: Mortality rate is high in patients with chronic obstructive pulmonary disease (COPD). Our aim was to investigate long-term mortality and associated risk factors in COPD patients previously hospitalized for a COPD exacerbation.Methods: A total of 256 patients from the Nordic countries were followed for 8.7 ± 0.4 years after the index hospitalization in 2000–2001. Prior to discharge, the St George’s Respiratory Questionnaire was administered and data on therapy and comorbidities were obtained. Information on long-term mortality was obtained from national registries in each of the Nordic countries.Results: In total, 202 patients (79%) died during the follow up period, whereas 54 (21%) were still alive. Primary cause of death was respiratory (n = 116), cardiovascular (n = 43), malignancy (n = 28), other (n = 10), or unknown (n = 5). Mortality was related to older age, with a hazard risk ratio (HRR) of 1.75 per 10 years, lower forced expiratory volume in 1 second (FEV1) (HRR 0.80), body mass index (BMI) <20 kg/m2 (HRR 3.21), and diabetes (HRR 3.02). Older age, lower BMI, and diabetes were related to both respiratory and cardiovascular mortality. An association was also found between lower FEV1 and respiratory mortality, whereas mortality was not significantly associated with therapy, anxiety, or depression.Conclusion: Almost four out of five patients died within 9 years following an admission for COPD exacerbation. Increased mortality was associated with older age, lower lung function, low BMI, and diabetes, and these factors should be taken into account when making clinical decisions about patients who have been admitted to hospital for a COPD exacerbation.Keywords: acute exacerbation, long-term mortality, co-morbidity, diabetes, lung function