OBJECTIVES: This analysis estimates the health care costs (hospitalisations and outpatient visits) due to respiratory and co-morbid diseases in a cohort of subjects with and without COPD in Sweden. METHODS: A cohort of individuals was identified in earlier clinical examinations of the general population within the Obstructive Lung Disease in Northern Sweden (OLIN) Studies. The cohort consisted initially of 993 subjects fulfilling criteria (GOLD) for COPD and an age- and gender matched control group of same size without obstructive lung function impairment. Since 2005, these subjects have been invited to yearly interviews and examinations. The participation rate has been high, above 85%. This analysis is based on resource use data collected in 2006 (n=772 COPD, n=802 non-COPD). Unit costs from the Northern health-care region price list of 2010 were used. RESULTS: The mean health-care costs of all diseases amounted to €1,421 (median €236) annually per subject with COPD compared to €1,127 (median €169) for subjects without COPD (p=0.16, non-parametric Mann-Whitney). The mean costs in relation to disease severity were (GOLD criteria severity stage; p-value COPD vs. non-COPD): €1,166 (mild; p=0.66), €1,755 (moderate; p=0.28), €2,223 (severe+very severe; p<0.01).  A minor part of the costs was attributable to respiratory diseases; 6.2% in non-COPD subjects and 10.5% in subjects with COPD. Respiratory disease costs were statistically significantly higher among subjects with COPD in all disease severity stages. CONCLUSIONS: The mean annual health-care costs were €294 (median €67) higher for subjects with COPD. The difference in costs between subjects with severe+very severe COPD and subjects without the disease was statistically significant.