Maricopa County Monitors Neonatal Abstinence Cases

Maricopa County health officials are monitoring cases of Neonatal Abstinence Syndrome among newborns exposed to drugs before birth, relying on hospital discharge data to identify affected infants.

NAS affects newborns under 28 days old who withdraw from substances their mothers used during pregnancy. While opioids account for most cases, exposure to benzodiazepines, barbiturates, and antidepressants can also trigger the condition.

The Maricopa County Department of Public Health analyzes hospital discharge records from all Arizona-licensed hospitals in the county, excluding federal facilities. Researchers identify NAS cases by searching for the ICD-10-CM diagnostic code P96.1, which indicates neonatal withdrawal from maternal drug use, following methodology established by the Council of State and Territorial Epidemiologists in 2019.

The department removes duplicate records to count each newborn only once, even if they had multiple hospital visits within 28 days of birth.

About 15.7% of NAS cases in the data lack a specific substance diagnosis code, listing instead "other drugs of addiction." Providers have continued using the general code because many substance-specific codes for newborn exposure only became available in October 2018.

Arizona healthcare facilities have been required to report NAS cases to the state's disease surveillance system since June 2017, but incomplete reporting led the county to rely on hospital discharge data instead.