Health care costs almost $400 more per year for patients with chronic obstructive pulmonary disease who have a history of asthma, compared with those without asthma, according to a study using the health care and demographic records of over 45,000 adults in British Columbia.

From 1997 to 2012, the average annual health care cost for patients with COPD + asthma (n = 22,565) was $391 higher than for COPD patients who had no history of diagnosed asthma (n = 22,565), reported Dr. Mohsen Sadatsafavi of the University of British Columbia, Vancouver, and his associates (Ann Am Thorac Soc. 2016 Feb;13[2]:188-96).

The largest component of that excess was medication costs, which were $476 higher for patients with COPD + asthma, with outpatient services ($92) and community care ($19) making smaller contributions. These excesses were somewhat offset by hospitalization costs, which were $196 less per year for the COPD + asthma group, the investigators said. (All costs in the study were given in Canadian dollars and have been converted here to U.S. dollars.)

Among the respiratory medications, the drug class with the largest difference was inhaled corticosteroids/long-acting beta-agonists, which cost almost $178 more per year for the COPD + asthma patients. Inhaled corticosteroids were next, with a cost excess of $64 annually, followed by long-acting muscarinic agents ($59), short-acting beta-agonists ($46) and leukotriene receptor agonists ($19), Dr. Sadatsafavi and his associates said.

All subjects were aged 40 years or older (average, 67.8 years for COPD only and 68 years for COPD + asthma), and 57% of each group was female. Individuals were excluded if their date of first asthma-related resource use was less than 2 years before their first date of COPD-related resource use, they noted.