Objective: Cerebral palsy (CP) is associated with prenatal, perinatal and postnatal factors. This is a retrospective case-control study aiming to determine the frequency of CP and examine risk factors for CP among infants cared for in the Neonatal Intensive Care Unit (NICU) covering Northwest Greece.
Design and patients: All neonates who were admitted to the NICU during the period 1989-2003 inclusive, and subsequently developed CP, were enrolled in the study, with matched controls. The incidence of CP was evaluated according to gestational age (GA): GA<34 weeks (group A) and GA>34 (group B), and study period: 1989-1996 (period I) and 1997-2003 (period II, during which intrauterine transfer and prenatal steroids were used).
Results: CP was diagnosed in 78 children, 55 in group A and 23 in group B. The incidence of CP increased significantly with decreasing GA. Survival without CP increased significantly in children of GA<34 weeks during period II. The main factors associated with CP, identified by multivariate analysis, were (odds ratios, confidence interval), for group A: being small for gestational age (SGA) (2.5, 1.2-4.5) and patent ductus arteriosus (PDA) (3.4, 1.3-9.2) in period I, periventricular leucomalacia (PVL) (27, 4.8-209), prolonged rupture of membranes (PROM) (5.6, 1.8-18) and duration of mechanical ventilation (1.1, 1.05-1.2) in period II, and for group B: SGA (3.6, 1.3-9.9), neonatal transfer (3.06, 1.2-7.6), duration of mechanical ventilation (1.1, 1.06-1.25) and sepsis-meningitis (4.3, 1.2-16).
Conclusion: Improvement in survival without CP was observed in infants of GA<34 weeks during the later period of the study, and risk factors for CP in preterm infants depended on the study period. PVL, PROM and PDA were the most powerful independent predictors of CP in children of GA<34 weeks and SGA, neonatal transfer and sepsis/meningitis in children of GA>34 weeks.