Adults Hospitalized with CAP Have Low Rates of Antiviral Treatment, More Severe Disease

PHILADELPHIA, PA—Adults hospitalized with all-cause community-acquired pneumonia (CAP) had low rates of influenza antiviral treatment, which was associated with a positive influenza result earlier in the course of illness as well as more severe disease, according to a study reported at IDWeek 2014.

Reasons for the underutilization of antiviral treatment warrant exploration,” stated Ikwo Oboho, MD, ScM, of the Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, in presenting these results.

Noting data on the use of influenza antiviral treatment among patients hospitalized with all-cause CAP are limited, Dr. Oboho and colleagues enrolled 2,320 adults with CAP between January 2010 and June 2012 at 5 hospitals in Chicago and Nashville. Based on their clinical judgment, the clinicians ordered influenza tests (eg, rapid, direct fluorescent antigen, polymerase chain reaction [PCR]) and prescribed antivirals.

“Nasopharyngeal /oropharyngeal specimens for influenza PCR testing were systematically collected for the study, but results were unavailable to clinicians,” she noted. The investigators defined treatment as receipt of an oseltamivir, an influenza antiviral agent, during hospitalization. They compared factors associated with receipt and non-receipt of oseltamivir during the influenza season, October to April, for each year.

Of 1,487 (64%) adults enrolled during influenza season, 180 (12%) received treatment. Among the 581 patients (39%) for whom clinicians ordered influenza tests (96%, PCR), 48 had a positive result and 37 (77%) received an oseltamivir. Of the 100 influenza cases that were positive, 41 patients received oseltamivir.

Compared with those who did not receive treatment, adults who received oseltamivir were younger, 54 (interquartile range [IQR] 42-66) vs. 58 years (IQR 47-71; P<0.01); admitted earlier during illness, 3 (IQR 2–6) vs. 4 (IQR 2–8) days (P=0.03); less likely to have a chronic condition,73% vs.78% (P=0.14), and more likely to need intensive care unit admission, 38% vs. 19% (P<0.01) or invasive mechanical ventilation, 47% vs. 24% (P<0.01).

Overall, clinicians ordered influenza tests in less than half of the patients. Results show that “among adults hospitalized with all-cause CAP during the influenza season, testing for influenza was uncommon and receipt of oseltamivir was low,” concluded Dr. Oboho. She added that in order to improve the appropriate use of influenza testing and antiviral medications per guidelines, interventions should be evaluated.