Respiratory viral infections in adults with and without chronic obstructive pulmonary disease

A longitudinal cohort study of older adults with chronic obstructive pulmon ary disease (COPD) who were stratified by FEV1 at enrollment was done to de fine the etiology, frequency, severity, and medical-care impact of respirat ory tract viral infections (RTVIs). Controls consisted of a group of subjec ts of comparable age with the patients. RTVIs were documented in 44% of obs erved acute respiratory illnesses in control subjects and in 27% of COPD su bjects, who were followed for mean periods of 35 and 26 mo, respectively. I n this heavily influenza-vaccinated cohort (similar to 90% vaccinated each year), picornaviruses, parainfluenza viruses, and coronaviruses were most c ommonly identified. Mean time to return to clinical baseline was approximat ely 2 wk in each group. Control and COPD subjects with mild airways obstruc tion (baseline FEV1 greater than or equal to 50% predicted) had few emergen cy-center visits or hospitalizations. Approximately half of COPD subjects w ith moderate/severe COPD (baseline FEV1 < 50% predicted) had at least one e mergency-center visit and/or hospitalization for acute respiratory illness. RTVIs were documented in 23% of hospitalizations and in 45% of patients ad mitted between December and March. RTVIs have a major impact on utilization of health care resources for COPD patients with moderate/severe airways ob struction.