Impact of oseltamivir treatment on influenza-related lower respiratory tract complications and hospitalizations.
BACKGROUND
Influenza causes lower respiratory tract complications (LRTCs), particularly bronchitis and pneumonia, in both otherwise healthy adults and those with underlying conditions. The aim of this study was to assess the effect of oseltamivir treatment on the incidence of LRTCs leading to antibiotic treatment and hospitalizations following influenza illness.


METHODS
We analyzed prospectively collected data on LRTCs and antibiotic use from 3564 subjects (age range, 13-97 years) with influenzalike illness enrolled in 10 placebo-controlled, double-blind trials of oseltamivir treatment.


RESULTS
In adults and adolescents with a proven influenza illness, oseltamivir treatment reduced overall antibiotic use for any reason by 26.7% (14.0% vs 19.1% with placebo; P<.001) and the incidence of influenza-related LRTCs resulting in antibiotic therapy by 55% (4.6% vs 10.3% with placebo; P<.001). In those subjects considered at increased risk of complications, 74 (18.5%) of 401 placebo recipients developed an LRTC leading to antibiotic use compared with 45 (12.2%) of 368 oseltamivir recipients (34.0% reduction; P =.02). Hospitalization for any cause occurred in 18 (1.7%) of 1063 placebo recipients compared with 9 (0.7%) of 1350 oseltamivir-treated patients (59% reduction; P =.02). In contrast, among subjects with an influenzalike illness but without a confirmed influenza infection, the incidence of LRTCs (6.7% vs 5.3%), overall antibiotic use (19.7% vs 19.3%), or hospitalizations (1.7% vs 1.9%) was similar between placebo and oseltamivir recipients, respectively.


CONCLUSIONS
Oseltamivir treatment of influenza illness reduces LRTCs, antibiotic use, and hospitalization in both healthy and "at-risk" adults.
Kaiser
Laurent
L
Hôpital Cantonal de Genève, Geneva, Switzerland.
Wat
Cynthia
C
Mills
Tracy
T
Mahoney
Paul
P
Ward
Penelope
P
Hayden
Frederick
F
D000081:Acetamides / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000998:Antiviral Agents / Q000627:therapeutic use*; D004311:Double-Blind Method; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D009980:Influenza A virus; D009981:Influenza B virus; D007251:Influenza, Human / Q000453:epidemiology / Q000628:therapy* / Q000821:virology*; D008875:Middle Aged; D053139:Oseltamivir; D011446:Prospective Studies; D012140:Respiratory Tract Diseases / Q000453:epidemiology / Q000628:therapy* / Q000821:virology*; D012307:Risk Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
D000081:Acetamides; D000900:Anti-Bacterial Agents; D000998:Antiviral Agents; D053139:Oseltamivir