Benzodiazepine use is associated with significantly increased risks of adverse respiratory outcomes in older adults with chronic obstructive pulmonary disease, researchers reported online April 17 in the European Respiratory Journal.
New benzodiazepine users were 45% more likely to receive outpatient respiratory medications and 92% more likely to visit the emergency department for respiratory reasons than were non–benzodiazepine users, reported Dr. Nicholas Vozoris of St. Michael’s Hospital and the University of Toronto and his associates.
"These findings are concerning, given that benzodiazepines are known to be frequently used among older adults with COPD and in suboptimal ways," the investigators wrote. "The findings suggest that the potential for adverse respiratory outcomes needs to be considered when administering benzodiazepines to older adults with COPD."
The retrospective population-based cohort study identified 177,355 adults with COPD who were at least 66 years old and lived in Ontario, Canada, during 2003-2010. The researchers used 1:1 propensity score matching without replacement to match 48,915 new benzodiazepine users with the same number of nonusers (Eur. Respir. J. 2014 April 17 [doi: 10.1183/09031936.00008014]).
New users of benzodiazepines were significantly more likely to be prescribed oral corticosteroids or respiratory antibiotics (relative risk, 1.45; 95% confidence interval, 1.36-1.54) and to visit the emergency department for COPD or pneumonia (RR, 1.92; 95% CI, 1.69-2.18).
Furthermore, in the subgroup of patients who had no exacerbation of COPD during the year before baseline, new benzodiazepine users had a significantly greater risk of receiving outpatient respiratory medications (RR, 1.63; 95% CI, 1.44-1.84), visiting an emergency department for COPD or pneumonia (RR, 2.46; 95% CI, 1.90-3.18), being hospitalized for either diagnosis (RR, 1.29; 95% CI, 1.07-1.56), or dying from any cause (RR, 1.19, 95% CI, 1.06-1.34).
The research is consistent with findings from previous smaller, shorter-duration studies, said Dr. Vozoris and his associates. They noted that their definition of COPD had a sensitivity of only 58%, which could limit the generalizability of the findings.
The Canadian Institutes of Health and the Institute for Clinical Evaluative Sciences funded the study. The investigators reported having no conflicts of interest.