Reduced antibiotic prescribing guided by CRP testing does not worsen outcomes in nursing home patients

Reference

Boere TM, van Buul LW, Hopstaken RM, et al. Effect of C reactive protein point-of-care testing on antibiotic prescribing for lower respiratory tract infections in nursing home residents: cluster randomised controlled trial. BMJ 2021;374:n2198.

Synopsis

This study was conducted in 11 nursing homes across the Netherlands. It included 84 physicians managing 241 patients with suspected lower respiratory infection (average age 84 years). Sites, rather than physicians or patients, were randomized to use either C-reactive protein (CRP) testing or provide usual care. Physicians at the CRP sites used the test at their discretion (and did so for 87% of patients) after receiving training on its use and interpretation. Antibiotic treatment was prescribed for 53.5% of the patients in the CRP group and 82.3% in the usual care group; patients in the CRP testing nursing homes had almost 5-fold higher odds of not being prescribed an antibiotic. There was no difference in mortality, the likelihood of hospital admission, or the full recovery rate between the 2 groups. I have 2 quibbles with this study: (1) There is a high likelihood of a Hawthorne effect, in which the participating physicians altered their prescribing because they were being watched; and (2) the unit of measure in this study was patients, although for purposes of determining whether physician practice is altered, the unit of measure should have been the 84 physicians (with only a measly average of 3 data points each).