The risk for attention-deficit/hyperactivity disorder was greater among preterm infants and infants with poor fetal growth, according to recent research published in Pediatrics.
“Each gestational week has significance for a child’s subsequent neurodevelopment and risk for [attention-deficit/hyperactivity disorder (ADHD)],” Minna Sucksdorff, MD, of the departments of child psychiatry and pediatrics at the University of Turku, Finland, and colleagues wrote. “We also showed that poor fetal growth increased the risk of ADHD.”
The researchers collected data from three Finnish nationwide registries of all singletons born from 1991 through 2005. Patients with ADHD (n = 10,321) were compared with a control cohort (n = 38,355) to determine the effects of preterm birth and fetal growth on developing ADHD.
Data showed that the risks for ADHD increased with each declining gestational week that a preterm infant was born. The risk for AHDH was significantly higher for infants born at weeks 23 and 24 (adjusted OR = 11.96; 95% CI, 3.6-39.72) than those born at week 43 (aOR = 0.99; 95% CI, 0.48-2.02). The researchers said the risk for ADHD remained moderately high until week 37 (aOR = 1.31; 95% CI, 1.16-1.47).
The risk for ADHD also was associated with poor fetal growth. Infants born small for gestational age had a risk for ADHD that ranged from significant, at a weight for gestational age 1 SD below the mean (aOR = 1.13; 95% CI, 1.04-1.24), to more than double the risk, at 2 SD below the mean (aOR = 1.8; 95% CI, 1.58-2.05).
“Becoming aware of the long-term outcomes of children born late preterm is noteworthy, because approximately 72% of infants born prematurely are born during that period,” the researchers wrote. “Thus, even a modest increase in the ADHD risk observed in this group, as seen in our data, results in a substantial number of ADHD cases at the population level.” – by David Costill
Disclosure: The researchers report no relevant financial disclosures.