Incidence of epilepsy in children born prematurely and small for gestational age at term gestation: A population-based cohort study.

AIM

This study assessed the incidence of epilepsy in preterm infants and those small for gestational age (SGA) at term and identified risk factors associated with higher epilepsy incidence in these children.

METHODS

We enrolled children (from 2000 to 2010) who were premature (n = 21 474) or SGA (n = 2206); we then included a matched control cohort (n = 94 720). Cox regression was used to assess the epilepsy risk in preterm and SGA children. To determine the associated factors for epilepsy, the preterm and SGA infants were divided into six groups according to the common complications related to brain development and were separated into three subgroups based on birthweight (BW).

RESULTS

The cumulative incidence of epilepsy was significantly higher in preterm or SGA children than in the control group. The overall incidence densities (per 1000 person-years) of epilepsy were: 0.37 in the control, 2.96 in the preterm, 2.90 in the SGA, 15.9 in the preterm with cerebral haemorrhage, 14.6 in the SGA with cerebral haemorrhage, 6.92 in the preterm with asphyxia, 3.82 in the SGA with asphyxia, 14.3 in the preterm with congenital brain anomalies, and 25.4 in the SGA with congenital brain anomalies cohorts. Infants with BW < 1000 g had a higher incidence of epilepsy than those with BW ≥2500 g.

CONCLUSIONS

Preterm and SGA infants had an increased risk of epilepsy in childhood, and the incidence of epilepsy increased with decreasing BW. Several perinatal factors (e.g. intracranial haemorrhage, birth asphyxia and congenital brain anomalies) are associated with a higher incidence of later epilepsy.