Abstract
Background:. CARESS tracks palivizumab use and outcomes in high-risk infants. We compared hazards for hospitalization for respiratory illness (RIH) and RSV (RSVH) in CAA infants versus those prophylaxed for other medical disorders (MD) and standard indications (SD).
Methods: Infants receiving ≥1 dose of palivizumab in 2005-2012 RSV seasons recruited from 32 Canadian sites. Utilization and hospitalization collected monthly.
Results: 13,310 infants enrolled (309 CAA, 1816 MD, 11185 SD). There were statistically significant group differences (p<0.05) in: enrolment and gestational age, birth and enrolment weight, proportions of: Caucasians, daycare attendance, smoking exposure, siblings, multiple birth, household crowding, and atopy.CAA infants had RIH rate of 12.9%; MD (9.9%); SD (5.9%) with significantly increased hazard of hospitalization compared to MD (HR = 1.47, 95%CI 1.04-2.10, p = 0.030) and SD (HR = 1.92, 95%CI 1.39-2.67, p < 0.0005). 40/309 CAA infants were hospitalized for RI, 32 were tested for RSV; 4 were positive (RSVH rate: 1.61% versus 2.06% (MD), 1.47% (SD). ByCox proportional hazard analysis, CAA did not increase hazard of first RSVH compared to MD or SD infants (χ2 = 0.79, df = 2, p = 0.67). After risk factor adjustment for daycare attendance, siblings, smoking exposure and crowding, the model was significant (χ2 = 66.1, df = 10, p < 0.0005); individual groups as risk factors remained insignificant (p = 0.73).
Conclusions: This is the largest report of CAA infants receiving palivizumab . Despite differences in risk factors, the groups appear to have similar hazards in terms of RSVH.
- © 2014 ERS
