Socioeconomic inequalities in neonatal intensive care admission rates.

OBJECTIVE To examine socioeconomic inequalities in neonatal intensive care (NIC) admissions relating to preterm birth, intrauterine growth restriction (IUGR), multiple births and other conditions. METHODS Retrospective review of all NIC admissions from 1996 to 2001 throughout a geographically defined region. Area deprivation indices were grouped into quintiles from least (1) to most (5) deprived. Admissions were classified by predefined hierarchical criteria. RESULTS The rate of admissions was 31.4 per 1000 births. There was a J-shaped relation with socioeconomic group (28.1 NIC admissions per 1000 in quintile 1, 34.0 in quintile 5 and below 28 in the other quintiles). The most deprived areas had a rate 19% above the regional average. The relation with socioeconomic group differed significantly according to primary reason for admission. The rates of admissions with significant prematurity (34% of all admissions) and IUGR as primary reason were highest in quintile 5 (18% and 41% above the regional average, respectively). This contrasted with the rate of admission for multiple birth which was highest in quintile 1 (45% above average). These differences provided the main explanation for the J-shaped overall curve. CONCLUSIONS Measures to alleviate deprivation and to improve the preterm birth and IUGR rates in deprived groups would have the greatest potential to reduce inequality in need for NIC admission. Efforts to achieve targets for reduction in infant mortality need to take account of the different effects of socioeconomic inequalities for different conditions and groups of infants.