Cigarette smoking in opioid-dependent pregnant women: neonatal and maternal outcomes

Abstract

Background: The relationship between cigarette smoking and neonatal and maternal clinical outcomes among opioid-agonist-treated pregnant patients is sparse.

Objectives: (1) Is smoking measured at study entry related to neonatal and maternal outcomes in pregnant women receiving opioid-agonist medication? (2) Is it more informative to use a multi-item measure of smoking dependence or a single-item measure of daily smoking? (3) Is the relationship between smoking at study entry and outcomes different between methadone and buprenorphine?

Methods: Secondary analyses examined the ability of the tobacco dependence screener (TDS) and self-reported past 30-day daily average number of cigarettes smoked, both measured at study entry, to predict 12 neonatal and 9 maternal outcomes in 131 opioid-agonist-maintained pregnant participants.

Results: Past 30-day daily average number of cigarettes smoked was significantly positively associated with total amount of morphine (mg) needed to treat neonatal abstinence syndrome (NAS), Adjusted Odds Ratio (AOR)=1.06 (95% CI: 1.02, 1.09), number of days medicated for NAS, AOR=1.04 (95% CI: 1.01, 1.06), neonatal length of hospital stay in days, AOR=1.03 (95% CI: 1.01, 1.05), and negatively associated with 1-AOR=.995 (95% CI: .991,.999) and 5-min Apgar scores, AOR=.996 (95% CI: .994,.998). Simple effect tests of the two significant TDS×medication condition effects found TDS was unrelated to non-normal presentation and amount of voucher money earned in the methadone [AORs=.90 (95% CI: .74, 1.08, p>.24) and 1.0 (95% CI: .97, 1.03, p>.9)] but significant in the buprenorphine condition [AORs=1.57 (95% CI: 1.01, 2.45, p<.05) and 1.08 (95% CI: 1.04, 1.12, p<.01)].

Conclusions: Regardless of prenatal methadone or buprenorphine exposure, heavier cigarette smoking was associated with more compromised birth outcomes.

Trial registration: ClinicalTrials.gov NCT00271219.

Keywords: Agonist treatment; Neonatal abstinence syndrome; Neonate; Opioid dependence; Pregnancy; Smoking.

Figure 1. Bar Charts of Neonatal Outcome Measures at Selected Values of Past 30-Day Average Number of Cigarettes Smoked

Poisson regression analyses were used to test the relationship between these 5 outcome variables and the past-30 day daily average number of cigarettes smoked, adjusting for medication condition, site, and estimated gestational age at study entry. Estimates are exponentiated parameter estimates. Estimates were calculated at 4 values of the predictor variable of past-30 day daily average number of cigarettes smoked: No cigarette smoking; below-average cigarette smoking, defined as 5.88 cigarettes/day (−1 SD); average cigarette smoking, defined as 13.66 cigarettes/day (Mean); and, above-average cigarette smoking, defined as 21.44 cigarettes/day (+1 SD).