Validation of hospital discharge coding for neonatal abstinence syndrome.

AIM: To validate the diagnostic discharge coding of neonatal abstinence syndrome (NAS) (International Classification of Diseases [ICD]-10-AM, P96.1). METHODS: Retrospective record review of infants diagnosed with NAS (P96.1) in a non-tertiary Australian hospital between 2000 and 2016. NAS criteria were predetermined to include the following: (i) maternal opioid use; (ii) infant requiring NAS medication and (iii) at least one score of ≥8 on the Finnegan Neonatal Abstinence Scoring Tool (FNAST). RESULTS: Of the 253 infants coded with P96.1, 82/146 (56%) opioid-exposed infants and 9/107(18%) infants exposed to non-opioid drugs only received withdrawal medication: sensitivity 56.2 (95% confidence interval: 47.7-64.3), specificity 91.6 (84.2-95.8%), positive predictive value (PPV) 90.1 (81.6-95.1%) and negative predictive value (NPV) 60.5 (52.5-68.0%) for all three criteria. Using the criterion of ≥1 FNAST score ≥8 resulted in 58.0 (51.3-64.4%) sensitivity, 63.6 (40.8-82.0%) specificity, 94.4 (88.8-97.4%) PPV and 12.6 (7.3-20.6%) NPV for identifying need for NAS medications. CONCLUSION: A diagnosis of P96.1 is highly specific and predictive but poorly sensitive for identifying opioid-exposed infants requiring medications for withdrawal.

Epidemiological Evidence for a Decreasing Incidence of Neonatal Abstinence Syndrome, 2000-11.

BACKGROUND: This study analyses the incidence of Neonatal Abstinence Syndrome (NAS) in a large geographically defined population in Australia. METHOD: Database linkage analysis of all births between 2000 and 2011 in New South Wales (NSW), Australia. The diagnosis of NAS was derived from hospital coding P96.1, 'Neonatal withdrawal symptoms from maternal use of drugs of addiction'. Temporal trends were studied by comparing epoch 1 (2000-05) with epoch 2 (2006-11). The relationship with changes in maternal factors was further analysed. RESULTS: The NAS was coded in 3842 of 1 022 263 live born infants (0.38%). NAS incidence peaked at 5.07 per 1000 live births in 2002, decreasing to 3.18 in 2011 and was negatively correlated with maternal age (r = -0.7). The rate of NAS in epoch 2 (3.4 per 1000 births, 95% CI 3.28, 3.58) was significantly lower than in epoch 1 (4.1 per 1000 births, 95% CI 3.96, 4.33). Epoch 2 mothers were significantly older (mean 29.8 years vs. 28.3 years), less likely to be multiparous (OR 0.7, 95% CI 0.6, 0.9) or smoke (OR 0.4, 95% CI 0.4, 0.5). They were more likely to engage in antenatal care earlier (mean first visit: 14.1 vs. 18.9 weeks). Most infants (~80%) were born at term (>37 weeks gestation). CONCLUSION: The incidence of NAS as a discharge diagnosis has decreased in our population since 2002. Mothers are also older and engaging earlier in prenatal care. Whether these changes alter NAS presentation and diagnosis or whether pregnant women are using drugs that do not cause typical NAS (e.g. amphetamines) is uncertain and requires further study.

Neonatal Abstinence Syndrome and High School Performance.

BACKGROUND AND OBJECTIVES: Little is known of the long-term, including school, outcomes of children diagnosed with Neonatal abstinence syndrome (NAS) (International Statistical Classification of Disease and Related Problems [10th Edition], Australian Modification, P96.1). METHODS: Linked analysis of health and curriculum-based test data for all children born in the state of New South Wales (NSW), Australia, between 2000 and 2006. Children with NAS (n = 2234) were compared with a control group matched for gestation, socioeconomic status, and gender (n = 4330, control) and with other NSW children (n = 598 265, population) for results on the National Assessment Program: Literacy and Numeracy, in grades 3, 5, and 7. RESULTS: Mean test scores (range 0-1000) for children with NAS were significantly lower in grade 3 (359 vs control: 410 vs population: 421). The deficit was progressive. By grade 7, children with NAS scored lower than other children in grade 5. The risk of not meeting minimum standards was independently associated with NAS (adjusted odds ratio [aOR], 2.5; 95% confidence interval [CI], 2.2-2.7), indigenous status (aOR, 2.2; 95% CI, 2.2-2.3), male gender (aOR, 1.3; 95% CI, 1.3-1.4), and low parental education (aOR, 1.5; 95% CI, 1.1-1.6), with all Ps < .001. CONCLUSIONS: A neonatal diagnostic code of NAS is strongly associated with poor and deteriorating school performance. Parental education may decrease the risk of failure. Children with NAS and their families must be identified early and provided with support to minimize the consequences of poor educational outcomes.

Dopamine D2 receptor gene polymorphisms in newborn infants of drug-using women.

OBJECTIVES: To determine the characteristics of dopamine D2 receptor gene (DRD2) polymorphisms in drug-exposed and unexposed neonates and the relationship to neonatal abstinence syndrome (NAS). DESIGN: Retrospective case-control analysis between drug-exposed and unexposed infants between DRD2 polymorphisms, drug exposure and NAS treatment. PATIENTS: Drug-exposed (n=48) and drug-free (n=49) infants born between March 1999 and December 2006. METHODS: Analysis of DNA for the Taq1A, -141Ins/Del and Ser311Cys DRD2 polymorphisms. Drug exposure was determined by antenatal maternal drug and alcohol history. Frequency measures of DRD2 polymorphisms were compared between drug-exposed infants, treatment NAS medication and with control infants. SETTING: Tertiary maternity hospital, Sydney, Australia. MAIN OUTCOME MEASURES: All infants were born in a good condition (25.7% <37 weeks gestation). Opiates (methadone and heroin) were used by 45 (93.8%) of drug-exposed mothers. The A2A2 allele was more common in drug-exposed infants (37 (77.0%) versus 23 (46.9%), p=0.003) but the A1A2 allele was more common in control infants (23 (46.9%) versus 4 (8.3%), p=0.00002). The-ins allele was more common in control (39 (79.6%) versus 20 (41.7%), p=<0.01) and unmedicated drug-exposed (14/25 (56%) versus 5/23 (21.7%), p=0.02) infants. The majority of infants (41 (83.7%) controls versus 41 (85.4%), p=1.000) expressed the least common, Ser polymorphism. CONCLUSIONS: DRD2 polymorphisms are detectable from DNA obtained from stored blood spots. The -ins allele is more common in control and unmedicated drug-exposed infants. Further study is recommended to explore postneonatal outcomes especially in relation to neuropsychiatric behaviours.

Effects of breast milk on the severity and outcome of neonatal abstinence syndrome among infants of drug-dependent mothers.

OBJECTIVE: The purpose of this research was to assess the effects of breast milk on the severity and outcome of neonatal abstinence syndrome. METHODS: We conducted a retrospective chart review of 190 drug-dependent mother and infant pairs. Patients were categorized according to the predominant type of milk consumed by the infant on the fifth day of life (breast milk: n = 85 or formula: n = 105). The Finnegan's scoring system was used to monitor withdrawal, and medication was commenced if there were 2 scores of > or = 8. RESULTS: Mean Finnegan scores were significantly lower in the breast milk group during the first 9 days of life even after stratifying for prematurity and exposure to polydrug and methadone. Significantly fewer infants required withdrawal treatment in the breast milk group. The median time to withdrawal occurred considerably later in breast milk group. In a multivariate analysis controlled for exposure to drugs of high risk of neonatal abstinence syndrome, polydrug, and prematurity, breast milk group was associated with lower need for neonatal abstinence syndrome treatment. CONCLUSIONS: Breast milk intake is associated with reduced neonatal abstinence syndrome severity, delayed onset of neonatal abstinence syndrome, and decreased need for pharmacologic treatment, regardless of the gestation and the type of drug exposure.