Methadone and the pregnant user: a matter for careful clinical consideration

Predictors of neonatal outcomes amongst a methadone- and/or heroin-dependent population referred to a multidisciplinary Perinatal and Family Drug Health Service

BACKGROUND AND AIMS

Although methadone maintenance therapy is the standard of care for opioid-dependent pregnant women, there exists controversy over the benefits and side effects of treatment to the neonate. Our aim was to document predictors of neonatal outcomes within an opioid-using population, with particular reference to methadone treatment in the context of continued heroin use.

METHODS

Analysis was performed on a cohort of 183 opioid-using pregnant women seen by the Sydney South West Area Health Service between 2004 and 2007 and between 2009 and 2011. Neonatal outcomes were analysed according to maternal opioid use: methadone only, methadone and heroin, or heroin only. Logistic regression was used to examine independent predictors of neonatal outcomes.

RESULTS

No difference in the frequency of low birth weight neonates or the rate of prematurity was found between the methadone-only, methadone-and-heroin and heroin-only groups (P = 0.30; P = 0.42). Methadone treatment was not found to increase the treatment requirement for neonatal abstinence syndrome compared with those using heroin only (P = 0.91). Women using methadone only were more likely to retain custody of their child at hospital discharge than women using methadone and heroin and heroin only (80.4, 59.0, 40.0%; P < 0.001).

CONCLUSIONS

Methadone treatment was beneficial in predicting the discharge custody status of the neonate. Engagement with antenatal care was found to reduce the likelihood of preterm birth and to be independently associated with the neonate being discharged in the care of the mother. Women who continue to use heroin should not be denied methadone treatment for fear of worse neonatal outcomes.

Auricular acupuncture for chemically dependent pregnant women: a randomized controlled trial of the NADA protocol

Background

The prevalence of maternal drug use during pregnancy in North America has been estimated to be as high as 6-10%. The consequences for the newborn include increased risk for perinatal mortality and ongoing physical, neurobehavioral, and psychosocial problems. Methadone is frequently used to wean women off street drugs but is implicated as a cause of adverse fetal/neonatal outcomes itself. The purpose of our study was to test the ability of maternal acupuncture treatment among mothers who use illicit drugs to reduce the frequency and severity of withdrawal symptoms among their newborns.

Methods

We randomly assigned chemically dependent pregnant women at BC Women’s Hospital in Vancouver, British Columbia to daily acupuncture treatments versus usual care. By necessity, neither our participants nor acupuncturists were blinded as to treatment allocation. Our primary outcome was days of neonatal morphine treatment for symptoms of neonatal withdrawal. Secondary neonatal outcomes included admission to a neonatal ICU and transfer to foster care.

Results

We randomized 50 women to acupuncture and 39 to standard care. When analyzed by randomized groups, we did not find benefit of acupuncture; the average length of treatment with morphine for newborns in the acupuncture group was 2.7 (6.3) compared to 2.8 (7.0) in the control group. Among newborns of women who were compliant with the acupuncture regime, we observed a reduction of 2.1 and 1.5 days in length of treatment for neonatal abstinence syndrome compared to the non-compliant and control groups, respectively. These differences were not statistically significant.

Conclusions

Acupuncture may be a safe and feasible treatment to assist mothers to reduce their dosage of methadone. Our results should encourage ongoing studies to test the ability of acupuncture to mitigate the severity of neonatal abstinence syndrome among their newborns.

Clinical Trial Registration

http://www.clinicaltrials.gov registry: W05-0041

The effects of maternally administered methadone, buprenorphine and naltrexone on offspring: review of human and animal data

Most women using heroin are of reproductive age with major risks for their infants. We review clinical and experimental data on fetal, neonatal and postnatal complications associated with methadone, the current "gold standard", and compare these with more recent, but limited, data on developmental effects of buprenorphine, and naltrexone. Methadone is a micro-opioid receptor agonist and is commonly recommended for treatment of opioid dependence during pregnancy. However, it has undesired outcomes including neonatal abstinence syndrome (NAS). Animal studies also indicate detrimental effects on growth, behaviour, neuroanatomy and biochemistry, and increased perinatal mortality. Buprenorphine is a partial micro-opioid receptor agonist and a kappa-opioid receptor antagonist. Clinical observations suggest that buprenorphine during pregnancy is similar to methadone on developmental measures but is potentially superior in reducing the incidence and prognosis of NAS. However, small animal studies demonstrate that low doses of buprenorphine during pregnancy and lactation lead to changes in offspring behaviour, neuroanatomy and biochemistry. Naltrexone is a non-selective opioid receptor antagonist. Although data are limited, humans treated with oral or sustained-release implantable naltrexone suggest outcomes potentially superior to those with methadone or buprenorphine. However, animal studies using oral or injectable naltrexone have shown developmental changes following exposure during pregnancy and lactation, raising concerns about its use in humans. Animal studies using chronic exposure, equivalent to clinical depot formulations, are required to evaluate safety. While each treatment is likely to have maternal advantages and disadvantages, studies are urgently required to determine which is optimal for offspring in the short and long term.

Medical illness and comorbidities in drug users: implications for addiction pharmacotherapy treatment

Providing effective medical care to those with substance use disorders can be a challenge to clinicians. In this article, we briefly summarize issues that occur frequently in the medical treatment of substance users. The focus of this article is twofold. The first is to briefly summarize common co-occurring medical illnesses in those manifesting substance use disorders with an emphasis on issues related to providing effective treatment for these diseases in this population. Using specific examples of frequently occurring comorbid medical illness in substance users, including infectious diseases (hepatitis C and HIV disease), sexually transmitted diseases, and pregnancy as examples, the complexities of medical care for this population is demonstrated. Second, this article addresses some of the difficulties encountered in pharmacotherapy aimed specifically at treatment of substance use disorders. For example, difficulties in managing concomitant opiate therapy in those requiring medications for medical illness that may have strong and adverse interactions with opiates are addressed. Adverse events reported for some substance use disorder pharmacotherapies are also highlighted. We conclude with a brief review of models of care that have been effective in addressing the needs of this challenging population that can provide additional means for enhancing the clinical care of substance users.