Association Between Intermittent Hypoxemia or Bradycardia and Late Death or Disability in Extremely Preterm Infants

IMPORTANCE: Extremely preterm infants may experience intermittent hypoxemia or bradycardia for many weeks after birth. The prognosis of these events is uncertain. OBJECTIVE: To determine the association between intermittent hypoxemia or bradycardia and late death or disability. DESIGN, SETTING, AND PARTICIPANTS: Post hoc analysis of data from the inception cohort assembled for the Canadian Oxygen Trial in 25 hospitals in Canada, the United States, Argentina, Finland, Germany, and Israel, including 1019 infants with gestational ages of 23 weeks 0 days through 27 weeks 6 days who were born between December 2006 and August 2010 and survived to a postmenstrual age of 36 weeks. Follow-up assessments occurred between October 2008 and August 2012. EXPOSURES: Episodes of hypoxemia (pulse oximeter oxygen saturation