Supplementary Material for: Recurrent Late-Onset Sepsis in Extremely Low Birth Weight Infants Is Associated with Motor Deficits in Early School Age

<b><i>Introduction:</i></b> Sepsis is regarded as a risk factor for brain injury in preterm infants. We herein hypothesize that extremely low birth weight infants (ELBWI, birth weight &lt;1,000 g) having survived recurrent blood culture-proven late-onset sepsis (LOS) episodes are more likely to have an adverse long-term neurologic outcome. <b><i>Methods:</i></b> In a large multicenter observational study of ELBWI ≤28 6/7 weeks, we evaluated the impact of recurrent LOS (blood culture-proven, after day 7 of life) on development at 5–6 years. Neurodevelopment, behavior, and motor qualities were tested by blinded investigators. Univariate and logistic regression analyses were performed. <b><i>Results:</i></b> The cohort consisted of 1343 ELBWI including 1,080 infants without LOS, 186 infants with one LOS, and 77 with recurrent LOS, i.e., 55 infants with two and 22 infants with three LOS episodes. After Bonferroni-Holm correction, multiple logistic regression analysis revealed recurrent sepsis to be significantly associated with adverse motor development (critical MABC-2 testing: 3.3 [1.5–7.3], <i>p</i> = 0.003, <i>p</i>_B = 0.012), whereas no significant impact of recurrent LOS was found on intelligence quotient and behavioral difficulties. Odds of having critical motor testing results for infants with recurrent LOS were 1.7 times (95% confidence interval 1.4–2.3) that of infants with one LOS. <b><i>Conclusion:</i></b> Recurrent sepsis in preterm infants is associated with adverse long-term motor development. However, infants with recurrent infections are also more likely to have preterm-related complications, and reasons for a worse neurodevelopmental outcome remain to be elucidated.