422 - Medical Marijuana Legalization in Oklahoma: Effects on Neonatal Exposure to Opiates

Poster Number: 422
Publication Number: 422.136

Shanna Rolfs, University of Oklahoma College of Medicine, Edmond, OK, United States; Lise DeShea, University of Oklahoma College of Medicine, Oklahoma City, OK, United States; Mike McCoy, Oklahoma Childrens Hospital at OU Health, Oklahoma City, OK, United States; Will Beasley, University of Oklahoma HSC, Oklahoma City, OK, United States; Edgardo Szyld, University of Oklahoma College of Medicine, oklahoma city, OK, United States; Abhishek Makkar, Oklahoma Childrens Hospital at OU Health, Oklahoma City, OK, United States

Background: The US opioid epidemic in the last two decades has been characterized by increases in opioid misuse, overdose deaths and neonatal opioid withdrawal syndrome. The implementation of medical cannabis laws has the potential to reduce maternal use of opioids and, therefore, neonatal exposure to the drugs. Alternatively, increased access to medical marijuana could be directly related to greater drug use. No prior studies could be found that examined the effect of legalized medical marijuana on positive drug test results in newborns.

Objective: To examine the association between Oklahoma’s legalization of medical marijuana and neonatal exposure to opioids.

Design/Methods: Retrospective chart review conducted at two sites (Oklahoma Children’s Hospital and Comanche County Memorial Hospital in Lawton). Results of cord, urine and meconium screens for eight categories of drugs (amphetamines, barbiturates, benzodiazepines, cocaine, ethanol, opiates, phencyclidine and tetrahydrocannabinol [THC]) were extracted from electronic medical records. Two review periods were compared: 19 months before Oklahoma’s medical marijuana law took effect and 19 months after legalization began. Chi square analyses were used to determine whether positive testing rates changed significantly for each drug category.

Results: A total of 16,804 babies were born alive at the two sites during the study period, with 1,502 infants (8.9% of the sample) tested for intrauterine drug exposure. The rate of positive THC tests per 1000 liveborn significantly increased from 16.2 per 1000 during the pre-law period to 22.2 per 1000 during the post-law period, p = 0.0044. Neonatal opioid exposure incidence showed a non-significant decrease from 7.6 positive tests per 1000 liveborn to 6.8 per 1000 from the pre-law to the post-law period, p = 0.517 Table 1). Similar drug positivity trends were noted at both centers (Table 2).Conclusion(s): Marijuana legalization was related to significant increases in positive test rates for THC, but no significant change/association was noted for neonatal exposure to opioids.
Table 1. Number and rates of positive drug tests before and after medical marijuana legalizationa No inferential statistics were calculated because of lack of positive tests.
b Chi square (df = 1) = 8.124, p = .0044, indicated a significant increase in the rate of babies testing positive. No other rates of significant tests changed pre-law versus post-law.
c Totals contain some babies testing positive for more than one drug, so rates per live birth would be inflated and unreliable. Therefore, the total rates were not calculated.
Table 2. Number and rates of positive drug tests by center before and after medical marijuana legalizationa No inferential statistics were calculated because of lack of positive tests.
b No ethanol tests were conducted at Lawton.
c Chi square (df = 1) = 5.69, p = 0.017, indicated THC testing rates increased significantly in Oklahoma City. No other Oklahoma City rates and none of the Lawton rates changed significantly.
d Totals contain some babies testing positive for more than one drug, so rates per live birth would be inflated and unreliable. Therefore, the total rates were not calculated.