Table 1.

Risk Factors for RSV Rehospitalization Among Infants Discharged From the NICU Before the RSV Season, Kaiser Permanente Medical Care Program (Northern California), 1992–1996

Risk FactorTotal nHospitalized for RSV (%)
Gestation, wk
 23–324387.3*,
  23–289911.1
  29–323396.2
 33–36§ 12831.8
Birth weight, g
 <15002648.7*
 ≥150014572.2
Oxygen therapy, d
 <2815972.3
 ≥2812414.5*
Assisted ventilation, d
 <14 days16082.4
 ≥14 days11314.2*
Date of NICU discharge
 December–August 12382.2
 September–November4835.8*
Maternal race
 White10653.2
 Asian2202.3
 Black1422.1
 Latino2314.3
Sex
 Female7623.3
 Male9593.1
Multiple gestation
 No13342.9
 Yes3874.1
  • * P ≤ .001.

  • Versus 33 to 36 weeks.

  • P = .1 versus 29 to 32 weeks.

  • § No difference in hospitalization risk was seen when only infants born at 33 to 35 weeks were included in this group.

  • Within the group of infants discharged between December and August, risk of RSV hospitalization during the subsequent RSV season was uniform.