The authors are commended for attempting to elucidate the poorly understood consequences of neonatal abstinence syndrome (NAS), a current global public health concern.1 Contrasting school test results from children diagnosed with NAS with matched controls and other children, the authors conclude that NAS is “strongly associated with poor and deteriorating school performance.” Determining academic risk for substance-exposed children could inform the need for early intervention services; therefore, the information could be important. We are concerned that this conclusion is not supported by the methodological approach, potentially leading to inaccurate perceptions by the public and policymakers.
The article uses only minimal criteria to match NAS cases. Mothers of infants of matched controls were older, far less likely to be Indigenous, with more education and more antenatal care; control infants had higher birth weights and were less likely to be admitted to an ICU. The baseline differences between groups increase the likelihood that observed associations were the result of unmeasured confounding. Unevaluated were myriad critical factors that significantly affect the developing child, including antenatal and postnatal maternal substance use and treatment, NICU versus other NAS care, length of NAS pharmacotherapy (if all cases received pharmacotherapy), child custody, violence exposure, psychiatric comorbidity and medications, poverty, lack of medical care, or any number of other factors that could independently or collectively affect development of a child of a mother with a substance use disorder.
Second, the diagnosis of NAS is potentially oversimplistic and represents a heterogeneous group of diagnoses ranging from any (minor) symptom of opioid withdrawal, opioid withdrawal necessitating treatment, or withdrawal symptoms caused or potentiated by other substances (such as selective serotonin reuptake inhibitors, alcohol, nicotine, benzodiazepines). Maternal polysubstance use is common among high-risk populations, and other antenatal exposures, such as teratogenic alcohol, could have an independent effect on school test performance. Because the population of mothers of infants with NAS is more likely to be Indigenous, and this status is related to higher alcohol consumption,2 this missing variable is notable. Similarly, nicotine exposure, also more likely in Indigenous pregnant women,3 is another important and unrecognized consideration. Lastly, there are multiple determinants of school performance, and reliance on standardized testing alone, particularly for Indigenous children, is overly simplistic in that it neglects the school environment and other factors affecting student engagement.4
Consequently, study results should be interpreted cautiously. Our principal concern is that the conclusion that NAS is associated with poor school performance will hark back to the “crack baby” epidemic of the 1980s; it took years of research to undo the damage that early reports of lower IQ in cocaine-exposed children portended. Many women with opioid use disorders seek necessary medication-assisted treatment, which can imply risk for NAS in the infant. The perhaps inaccurate association between NAS and poor academic outcomes may drive women away from essential treatment, which is damaging to public health. Long-term outcomes of opioid-exposed infants and those with NAS remain an important area of inquiry. There is an urgent need for well-funded, prospective studies evaluating developmental outcomes of this vulnerable population.
POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.
- Oei JL,
- Melhuish E,
- Uebel H, et al
- Ockenden L
- Copyright © 2017 by the American Academy of Pediatrics