RISK-FACTORS FOR CEREBRAL-PALSY - A CASE-CONTROL STUDY IN GREECE

The purpose of this study was to investigate the relation between a se ries of maternal, antenatal, perinatal, socioeconomic and environmenta l variables and the occurrence of cerebral palsy (CP) in a setting dif ferent from those in which previous analytic epidemiologic studies had been undertaken. The study was of case-control design and included 10 3 children with cerebral palsy born between 1984 and 1988 and resident s of the Greater Athens area at any time during 1991 and 1992. Control s were chosen among the neighbors of the index case or were healthy si blings of children with neurological diseases other than CP seen by th e same neurologists as the children with CP; a total of 254 control ch ildren were eventually included. Statistical analysis was done by mode ling the data through unconditional logistic regression. Statistically significant (p<0.05) risk factors of potential causal importance were : twin membership (OR=10.2), gestational age (OR=0.5 per 4 weeks), bir th weight conditional on gestational age (OR=0.9 per 100 g), congenita l malformations (OR=7.5), unhealthy placenta (OR=6.6), placenta previa (6 cases, no controls), abnormal amniotic fluid (OR=3.6), head circum ference more than 36 cm (OR=9.0), general anesthesia during labor (OR= 4.3), forceps delivery (OR=6.8), and birth trauma (OR=11.5). Among chi ldren with no identifiable prenatal risk factors there was no excess p revalence of one or more perinatal risk factors in CP cases compared t o controls, which implies that the latter factors impart their effect through interactions with co-existing prenatal or other risk factors.