Complications in preterm infants. Clinical and genetic risk factors

Complications which are frequently observed in preterm infants, such as intraventricular hemorrhage and bronchopulmonary dysplasia (BPD), are still major determinants of mortality and long-term morbidity. This article gives a review of clinical and genetic risk factors for complications in preterm infants with a birth weight below 1500 g. An assessment of published epidemiological data and analysis of the current databank of the German Neonatal Network were carried out. During the last 5 years no relevant decline in the prevalence of typical complications has been observed. All complications were associated with unfavorable short-term and long-term outcomes. Clinical risk factors for complications were identified by epidemiological studies; however, the pathophysiology of many complications has not yet been clarified. Genetic studies have failed to identify specific biochemical pathways involved in the occurrence of typical complications. More recent genetic trial designs, such as Mendelian randomization studies, are basically feasible in preterm infants and will hopefully contribute to identification of relevant pathways and biomarkers in the near future. The reduction of complications associated with preterm birth will be a major goal in the forthcoming years as this will be one of the few opportunities to achieve a durable reduction in short-term and long-term morbidity.