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

Hannah Uebel; Ian M Wright; Lucy Burns; Lisa Hilder; Barbara Bajuk; Courtney Breen; Mohamed E Abdel-Latif; Meredith Ward; John Eastwood; John M Feller; Janet Falconer; Sara Clews; Ju Lee Oei

doi:10.1111/ppe.12282

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

Paediatr Perinat Epidemiol. 2016 May;30(3):267-73. doi: 10.1111/ppe.12282. Epub 2016 Feb 5.

Authors

Hannah Uebel¹, Ian M Wright^{2

3}, Lucy Burns⁴, Lisa Hilder^{1

5}, Barbara Bajuk⁶, Courtney Breen⁴, Mohamed E Abdel-Latif^{7

8}, Meredith Ward^{1

9}, John Eastwood^{1

10

11}, John M Feller^{1

12}, Janet Falconer¹³, Sara Clews¹³, Ju Lee Oei^{1

9

11}

Affiliations

¹ School of Women's and Children's Heath, University of New South Wales, Kensington, NSW, Australia.
² Illawarra Health and Medical Research Institute and Graduate School of Medicine, The University of Wollongong, Wollongong, NSW, Australia.
³ Department of Paediatrics, The Wollongong Hospital, Wollongong, NSW, Australia.
⁴ National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
⁵ Centre for Big Data Research in Health, University of New South Wales, Sydney, NSW, Australia.
⁶ Perinatal Services Network, Westmead, NSW, Australia.
⁷ Department of Neonatology, The Canberra Hospital, Garran, ACT, Australia.
⁸ Faculty of Medicine, the Australian National University, Deakin, ACT, Australia.
⁹ Department of Newborn Care, Royal Hospital for Women, Randwick, NSW, Australia.
¹⁰ Sydney Local Health District, Sydney, NSW, Australia.
¹¹ Ingham Institute of Applied Medicine, University of New South Wales, Liverpool, NSW, Australia.
¹² Sydney Children's Hospital, Randwick, NSW, Australia.
¹³ The Langton Centre, Surry Hills, NSW, Australia.

PMID: 26849178
DOI: 10.1111/ppe.12282

Abstract

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.

Keywords: incidence; linkage; neonatal abstinence syndrome.

MeSH terms

Adolescent
Adult
Australia / epidemiology
Female
Health Knowledge, Attitudes, Practice
Hospitalization / trends*
Humans
Incidence
Infant
Infant Mortality / trends*
Infant, Newborn
Information Storage and Retrieval
Male
Neonatal Abstinence Syndrome / epidemiology*
Neonatal Abstinence Syndrome / etiology
New South Wales / epidemiology
Opioid-Related Disorders / complications
Opioid-Related Disorders / epidemiology*
Pregnancy
Pregnancy Complications / epidemiology*
Pregnancy Complications / etiology