Preeclampsia and cerebral palsy in low-birth-weight and preterm infants: Implications for the current "ischemic model" of preeclampsia

Objective. One of the prevailing hypotheses for the pathogenesis of preecla mpsia is the "ischemic model." It assumes that reduced uteroplacental perfu sion is the primary step and the point of convergence of diverse pathogenic processes in the development of preeclampsia. One might expect a fetus und er such "ischemic conditions" to be at an increased risk of later developme nt of cerebral palsy (CP). The objective of this study was to test the hypo thesis that maternal preeclampsia increases the risk of CP in preterm and l ow-birth-weight infants. Methods. A meta-analysis was performed based on published articles identifi ed by searching computerized databases (MEDLINE, EMBASE, CINAHL. Current Co ntents. Biological Abstracts. and Dissertation Abstracts) from 1966 through 1999. Ten observational studies on the association between preeclampsia an d CP were identified based on prespecified inclusion criteria. Two independ ent reviewers extracted data and assessed the methodological quality of eli gible articles. Odds ratios (OR) of CP for preeclampsia from individual stu dies were pooled. Main Outcome Measure. Cerebral palsy. Results. In case-control studies, preeclampsia was associated with a statis tically significant decreased risk of CP [pooled adjusted OR, 0.50; 95% con fidence interval (CI), 0.33-0.81: p < 0.01]. In cohort studies. preeclampsi a was associated with a nonstatistically significant reduced risk of CP (po oled OR, 0.91;95% CI, 0.35-2.41: p > 0.05). Conclusions. Preeclampsia may be associated with a decreased risk of CP in preterm and low-birth-weight infants. This challenges the currently held be lief that reduced uteroplacental perfusion is the unique pathophysiological process in preeclampsia.