Meta analysis of the relationship between small for gestational age and attention deficit/hyperactivity disorder

Objective To systematically review and meta-analyze the risk of small for gestational age (SGA) individuals to develop attention-deficit/hyperactivity disorder in childhood.Methods The cohort studies and case-control studies on the incidence of ADHD in underage SGA were searched in the Wan-fang database, CNKI, VIP, Pub Med and Cochrane databases, then the meta-analyses were conducted by using Stata 12.0 software based on the screened literature, the extracted data, and the evaluated methodological quality.Results In 9 studies, researchers showed that SGA subjects have a higher ADHD risk (OR: 1.63; 95%CI: 1.25-2.13). In subgroup analyses, studies relying on a categorical diagnosis showed SGA increased the risk of ADHD in childhood (OR: 2.55; 95%CI: 1.42-4. 56). We drew data from studies on ADHD symptomatology and found insignificant associations with inattention (OR: 1.34;95%CI: 0.98-1.83) and hyperactivity/impulsivity (OR: 1.27; 95%CI: 0.66-2.44) symptoms when compared with controls.Conclusion SGA subjects may have an increased risk of ADHD compared with controls, however, the results need further evaluation by high-quality clinical research.