CHICAGO – A study that compares babies who develop neonatal abstinence syndrome (NAS) with a control group of healthy newborns found largely what researchers expected to see – lower gestational ages, lower birth weights, and substance use in 100% of the mothers in the affected group. It’s when they looked at the control group of healthy newborns and their mothers that they got a surprise.
“Something that was very alarming in our study is [that] one in four of the control mothers was also positive for illicit drugs. That is something we definitely didn’t expect,” said Pallavi Karunakaran MD, a pediatric resident at Children’s Hospital of Michigan in Detroit.
The investigators compared 222 infants diagnosed with NAS and 490 healthy baby controls through a chart review at Hutzel Women’s Hospital in Detroit during Nov. 2011-Dec. 2016. Among the NAS infants, 80% were white, and among controls, 89% were white.The investigators also looked at maternal characteristics in both groups, with data available on 198 mothers whose babies developed the syndrome and 490 controls. “Interestingly enough, we expected that the mothers of the NAS babies would have some kind of drug use, [but] a lot of the NAS cohort mothers tested positive for additional drugs, other than methadone, which is usually how babies end up developing neonatal abstinence syndrome,” Dr. Karunakaran said at the annual meeting of the American Academy of Pediatrics. Drug use in mothers of affected babies included opioids among 81% (including methadone for 70%); heroin, 42%; cocaine, 29%; marijuana, 26%; benzodiazepines, 18%; buprenorphine, 6%; and barbiturates, 2%.
Among the control group mothers, drug use included marijuana among 20.4%; opioids, 1.8%; cocaine, 1.2%; benzodiazepines, 0.6%; heroin, 0.2%; and barbiturates, 0.2%.
Mean gestational age for affected infants was 38 weeks versus 39 weeks in controls, a significant difference (P less than .001). Mean birth weight for affected infants was 2,930 grams versus 3,145 grams in controls (P = .018). The average length of hospital stay was 21 days for infants who developed NAS, compared with 3 days among control infants (P less than .001). Mean Apgar scores were not significantly different between groups.
“The next step in terms of taking care of our population – is we’re trying to see how we can catch those one in four control mothers who are having well babies because we want to make sure we’re also taking care of them while they’re pregnant,” Dr. Karunakaran said. “If they’re involved in drug use, we want to get them the right resources and the right doctors they may need.”
Dr. Karunakaran had no relevant financial disclosures.