Psychosocial treatments for cocaine dependence: the role of depressive symptoms

Background

The association between cocaine use and depression has been frequently observed. However, less is known about the significance of depression in the treatment of cocaine use disorders. This study examined possible interrelations between drug use and depression severity among cocaine-dependent patients in psychosocial treatments for cocaine dependence.

Methods

Monthly assessed drug use and depression severity scores of N = 487 patients during 6-month psychosocial treatments for cocaine dependence were analyzed using hybrid latent growth models.

Results

Results indicated a moderate but statistically significant (z = 3.13, p < .01) influence of depression severity on increased drug use in the upcoming month, whereas drug use did not affect future depression severity.

Conclusions

Findings suggest that depression symptoms are an important predictor of drug use outcomes during psychosocial treatments for cocaine dependence and, hence, underline the importance of adequately addressing depression symptoms to improve treatment outcomes.     

Smoke-free policies in drinking venues predict transitions in alcohol use disorders in a longitudinal U.S. sample

Background

Smoke-free legislation prohibiting smoking in indoor public venues, including bars and restaurants, is an effective means of reducing tobacco use and tobacco-related disease. Given the high comorbidity between heavy drinking and smoking, it is possible that the public health benefits of smoke-free policies extend to drinking behaviors. However, no prior study has examined whether tobacco legislation impacts the likelihood of alcohol use disorders (AUDs) over time. The current study addresses this gap in the literature using a large, prospective U.S. sample.

Method

Using data from the National Epidemiological Survey on Alcohol and Related Conditions (NESARC), we utilized logistic regression to examine whether the implementation of state-wide smoke-free legislation in bars and restaurants between Waves I (2001–2002) and II (2004–2005) predicted changes in DSM-IV AUD status (remission, onset, recurrence) in current drinkers at Wave I (n = 19,763) and participants who drank in public ≥once per month (n = 5913).

Results

Individuals in states that implemented smoke-free legislation in drinking venues had a higher likelihood of AUD remission compared to participants in states without such legislation. Among public drinkers, smoke-free legislation was associated with a greater likelihood of AUD remission and a lower likelihood of AUD onset. These findings were especially pronounced among smokers, men, and younger age groups.

Discussion

These results demonstrated the protective effects of smoke-free bar and restaurant policies on the likelihood of AUDs; furthermore, these findings call attention to an innovative legislative approach to decrease the morbidity and mortality associated with AUDs.     

Low-dose naltrexone augmentation of nicotine replacement for smoking cessation with reduced weight gain: A randomized trial

Background

Fear of weight gain is a significant obstacle to smoking cessation, preventing some smokers from attempting to quit. Several previous studies of naltrexone yielded promising results for minimization of post-quit weight gain. Given these encouraging findings, we endeavored to test whether minimization of weight gain might translate to better quit outcomes for a population that is particularly concerned about gaining weight upon quitting.

Methods

Smokers (N = 172) in this investigation were prospectively randomized to receive either 25 mg naltrexone or placebo for 27 weeks (1 week pre-, 26 weeks post-quit) for minimization of post-quit weight gain and smoking cessation. All participants received open label therapy with the nicotine patch for the first 8 weeks post-quit and behavioral counseling over the 27-week treatment. The 2 pre-specified primary outcomes were change in weight for continuously abstinent participants and biologically verified end-of-treatment 7-day point-prevalence abstinence at 26 weeks after the quit date.

Results

The difference in weight at 26 weeks post-quit between the naltrexone and placebo groups (naltrexone: 6.8 lbs ± 8.94 vs placebo: 9.7 lbs ± 9.19, p = 0.45) was not statistically different. Seven-day point-prevalence smoking abstinence rates at 26 weeks post-quit was not significantly different between the 2 groups (naltrexone: 22% vs placebo: 27%, p = 0.43).

Conclusions

For smokers high in weight concern, the relatively small reduction in weight gain with low-dose naltrexone is not worth the potential for somewhat lower rates of smoking abstinence.     

The reinforcing value of alcohol in a drinking to cope paradigm

Background

Alcohol use is often regarded as a means of coping with sadness and distress. The present research was conducted to explore the relation between negative mood and the reinforcing value of alcohol, while clarifying the role of coping motives.

Methods

Participants with a history of recent alcohol use (N = 44; 72% female) attended a laboratory session and were randomly assigned to either a negative (n = 22) or a neutral (n = 22) mood condition. A manipulation check confirmed that participants in the negative mood condition, but not the neutral mood condition, displayed a significant increase in negative affect. The multiple choice procedure (MCP) was used to measure the reinforcing value of alcohol after the mood manipulation.

Results

Regression models employing the MCP crossover point as the dependent variable and mood condition (neutral or negative) and drinking to cope as predictors indicated that a model with an interaction term accounted for the most variance.

Conclusions

These results suggest that the relation between mood and the reinforcing value of alcohol is moderated by drinking to cope, and help clarify the conditions under which drinking to cope may lead to negative outcomes.     

Use patterns and self-reported effects of Salvia divinorum: An internet-based survey

Background

There is growing use of Salvia divinorum (SD), a psychoactive plant that produces hallucinogen-like effects through a kappa opioid receptor (KOR) mechanism. Little is known about KOR agonist effects in humans and about users of SD.

Objectives

To characterize the reasons, methods, and reported consequences of SD use.

Methods

Individuals reading SD-related pages of a drug-information website were invited to anonymously complete an online questionnaire if they had used SD.

Results

Participants (N = 500) were 92.6% male and 23.4 ± 8.7 (mean ± s.d.) years old. They had used a median of six times (range 1-250). 80.6% probably or definitely would use SD again. Most participants (92.6%) typically smoked or vaporized SD product. When smoked, the drug's main effects were estimated to last 14.1 ± 12.8 (range 0.5-120) minutes. When asked to compare SD effects to other methods of altering consciousness, the most common answer was that SD was unique (38.4%). 25.8% reported persisting (≥24 h) positive effects (often described as increased sense of well-being) on at least one occasion. 4.4% reported persisting negative effects (most often anxiety).

Conclusions

SD is typically smoked, acute effects are brief, and persistent adverse effects are uncommon. In addition to acute hallucinogenic effects, SD may produce subacute increases in subjective well-being. Such a subacute effect would be unusual for a drug that is used non-medically, as withdrawal from other drugs typically either does not affect mood or causes dysphoria. Findings from this convenience sample should be confirmed and extended using surveys of random samples and controlled clinical studies.     

Depressive mood and tobacco use: moderating effects of gender and emotional attention

Introduction

Depressive symptomatology is a predictive variable of tobacco use. The objective of the present study was to evaluate the influence that this symptomatology has on tobacco use when moderated by emotional attention.

Methods

A total of 289 participants (127 males, 162 females) completed a survey to measure perceived emotional intelligence, depressive symptomatology, tobacco use and sociodemographic variables. Results were analyzed using a multiple regression model that included self-perceived emotional attention as a moderating variable.

Results

In women, an interaction was found between depressive symptomatology and gender for predicting the number of cigarettes smoked (t = 2.45; p = .01), but not in men (t = −.74; p = .45). This interaction was moderated by emotional attention (t = 2.83; p = .005), such that women with medium and high levels of attention consumed a larger number of cigarettes.

Conclusions

In women, the effect of depressive symptomatology on tobacco use was moderated by the amount of attention that women paid to those symptoms. Such a moderating effect of attention was not observed in men. We recommend that smoking cessation programs incorporate interventions designed specifically for women, in particular to help them manage depressive symptomatology.     

The psychological impact of heavy drinking among the elderly on their co-residents: the 10/66 group population based survey in the Dominican Republic

Background

There is very limited literature on alcohol use among the elderly and little is known about the impact it has on family and caregivers, especially in low and middle income countries.

Aim

To estimate the independent effect of heavy alcohol use among the elderly on the psychological health of their co-residents.

Methods

This is a secondary analysis using data from the comprehensive cross-sectional survey of the 10/66 dementia research group population-based research programme in the Dominican Republic. The characteristics of the elderly participants as well as the co-residents were described. The independent association of heavy drinking among the participants with psychological morbidity in their co-residents was estimated. Different models were generated to rule out potential mediating effects of disability and behavioural symptoms.

Results

Prevalence of heavy alcohol use in the elderly in Dominican Republic was 10.6%. There was a statistically significant independent effect of heavy alcohol use by the elderly on their co-residents mental health (PR = 1.47; 95% CI 1.07-2.01) which was not accounted by disability (Sobel-Goodman test, p = 0.15). Severity of psychological and behavioural symptoms partially (29.1% of the total effect) explained this association (Sobel-Goodman mediation test, p = 0.006).

Conclusions

Health services for the elderly in low and middle income countries will have to be configured around detection of alcohol problems among the elderly as well as offering appropriate support to their co-residents.     

Effects of cigarette smoking status on delay discounting in schizophrenia and healthy controls

Background

Delay discounting is a measure of future-oriented decision-making and impulsivity. Cigarette smoking is associated with rapid discounting of the value of delayed outcomes. In schizophrenia, however, cigarette smoking improves certain neurocognitive impairments associated with the disorder which may explain the high smoking rates in this population. This study examined the relationship between cigarette smoking and delay discounting in schizophrenia and control participants.

Methods

A total of N = 130 participants, including those with schizophrenia (n = 68) and healthy controls (n = 62) were assessed on the Kirby Delay Discounting Task and compared across smoking status (smokers; non-smokers) and smoking history (current, former; never smokers).

Results

Smokers exhibited higher discounting rates (i.e., were more impulsive) than non-smokers of the same diagnostic group. Current and former smokers with schizophrenia exhibited similar and significantly higher discounting rates than never smokers, suggesting that in schizophrenia delay discounting is a trait-dependent phenomenon independent of current cigarette smoking. Consistent with previous studies, there was a trend for higher discounting rates in control current smokers compared to control former and never smokers.

Conclusions

Smokers with and without schizophrenia have higher rates of delay discounting than non-smokers. However, in schizophrenia, rapid delay discounting appears to be a trait associated with having ever been a smoker (i.e., current and former smoking).     

Prevalence and factors related to syringe sharing behaviours among female injecting drug users who are also sex workers in China

Background

Female injecting drug users who are sex workers (IDUFSWs) are at high risk of contracting HIV. They may bridge HIV transmissions from injecting drug users to clients of female sex workers.

Methods

A total of 216 non-institutionalised IDUFSWs were recruited by snowball sampling methods. Anonymous face-to-face interviews were conducted to collect data. Univariate, multivariate and hierarchical logistic regression models were fitted to investigate the associations between background characteristics, cognitive variables, psychological stress and syringe sharing behaviours among IDUFSWs.

Results

Respectively 33.8% and 27.8% of the respondents injected drugs with others’ used syringes and gave used syringes to others for drug injection in the last month. These two syringe sharing behaviours were significantly associated with inconsistent condom use during commercial sex (OR = 5.00 and 1.92, p < 0.05). Over 90% of the respondents reported at least one type(s) of psychological distress included in this study. Adjusting for significant background variables, all variables that are related to the Theory of Planned Behaviour (attitude, norm, perceived control and behavioural intention) and psychological distress (except for depression) were significantly associated with injecting drugs with others’ used syringes (adjusted OR = 2.08-6.25, p < 0.05), whilst variables related to perceived control, behavioural intention and insomnia were significantly associated with providing used syringes to others for injection (adjusted OR = 2.00-3.56, p < 0.05). In two separate summary multivariate models, variables related to the Theory of Planned Behaviours and psychological distress were independently associated with injecting drugs with others’ used syringes (OR = 1.98-4.02, p < 0.05) and giving used syringes to others for injection (OR = 2.06-3.59, p < 0.05).

Conclusions

Syringe sharing behaviours were prevalent among IDUFSWs and were associated with cognitive and psychological factors. Effective integrative intervention programmes targeting IDUFSWs are warranted.     

Deficits in default mode network activity preceding error in cocaine dependent individuals

Background

Cocaine dependence is associated with cognitive deficits and altered task-related cerebral activation in cognitive performance (see Li and Sinha, 2008, for a review). Relatively little is known whether these individuals are also impaired in regional brain activation of the default mode network (DMN). We demonstrated previously that greater activation of the default brain regions precedes errors in a stop signal task performed by healthy controls (SST, Li et al., 2007). We seek to determine whether individuals with cocaine dependence are impaired in DMN activity, specifically activity preceding error, as compared to the healthy people. We also examine the relation to years of cocaine use.

Methods

Individuals with cocaine dependence (CD, n = 23) and demographics-matched healthy controls (HC, n = 27) performed a SST that employed a tracking procedure to adjust the difficulty of stop trials and elicit errors approximately half of the time. Blood oxygenation level dependent (BOLD) signals of go trials preceding stop error as compared to those preceding stop success trials were extracted with generalized linear models using statistical parametric mapping.

Results

HC showed activation of bilateral precuneus and posterior cingulate cortices and ventromedial prefrontal cortex (vmPFC) preceding errors during the SST. In contrast, despite indistinguishable stop signal performance, CD did not show these error predicting activations. Furthermore, the effect size of error-preceding vmPFC activation was inversely correlated with years of cocaine use.

Conclusions

These findings indicate DMN deficits and could potentially add to our understanding of the effects of chronic cocaine use on cerebral functions in cocaine dependence. Work to further clarify potential changes in functional connectivity and gray matter volume is warranted to understand the relevance of DMN to the pathology of cocaine misuse.     

In vitro P-glycoprotein efflux inhibition by atypical antipsychotics is in vivo nicely reflected by pharmacodynamic but less by pharmacokinetic changes

Background

P-glycoprotein (P-gp), an efflux transporter of the blood-brain barrier, limits the access of multiple xenobiotics to the central nervous system (CNS). Thus drug-dependent inhibition, induction or genetic variation of P-gp impacts drug therapy.

Methods

We investigated atypical antipsychotics and their interaction with P-gp. Amisulpride, clozapine, N-desmethylclozapine, olanzapine, and quetiapine were assessed in vitro on their inhibitory potential and in vivo on their disposition in mouse serum and brain, and behaviourally on the RotaRod test. In vivo wildtype (WT) and mdr1a/1b double knockout mice (mdr1a/1b (−/−, −/−); KO) were investigated.

Results

In rhodamine 123 efflux assay drugs inhibitory potency to P-gp could be ranked quetiapine > N-desmethylclozapine > clozapine > olanzapine. When treating WT and KO mice i.p. and assessing brain and serum levels by HPLC analysis, P-gp expression has the highest but a rather short effect on the distribution of amisulpride, whereas the others ranked N-desmethylclozapine > olanzapine > quetiapine > clozapine; contrasted by in vivo behavioral changes at various time points. Here quetiapine > clozapine > olanzapine impacts behavior most when P-gp is lacking. Present results indicate the relevance of P-gp expression for CNS-drug therapy.

Conclusions

Combination of in vitro, and in vivo methods highlights that inhibitory potency did not reflect P-gp related drug disposition. But, when drugs were ranked for inhibitory potency, this order is reflected in pharmacodynamic changes or vice versa. Pharmacodynamic effects otherwise were at most correlated to drug brain levels, which however, were present only to a limited extent (by positron emission tomography) accessible in humans.     

Flunitrazepam in combination with alcohol engenders high levels of aggression in mice and rats

Rationale

Higher doses of benzodiazepines and alcohol induce sedation and sleep; however, in low to moderate doses these drugs can increase aggressive behavior.

Objectives

To assess firstly the effects of ethanol, secondly the effects of flunitrazepam, a so-called club drug, and thirdly the effects of flunitrazepam plus alcohol on aggression in mice and rats.

Methods

Exhaustive behavioral records of confrontations between a male resident and a male intruder were obtained twice a week, using CF-1 mice and Wistar rats. The salient aggressive and non-aggressive elements in the resident's repertoire were analyzed. Initially, the effects of ethanol (1.0 g/kg), and secondly flunitrazepam (0; 0.01; 0.1; and 0.3 mg/kg) were determined in all mice and rats; subsequently, flunitrazepam or vehicle, given intraperitoneally (0; 0.01; 0.1; and 0.3 mg/kg) was administered plus ethanol 1.0 g/kg or vehicle via gavage.

Results

The most significant finding is the escalation of aggression after a moderate dose of ethanol, and a low dose of flunitrazepam. The largest increase in aggressive behavior occurred after combined flunitrazepam plus ethanol treatment in mice and rats.

Conclusions

Ethanol can heighten aggressive behavior and flunitrazepam further increases this effect in male mice and rats.     

Malnutrition in a population of HIV-positive and HIV-negative drug users living in Chennai, South India

Background

Malnutrition is a strong predictor of poor outcomes in people living with HIV (PLHIV). Drug users are at increased risk of malnutrition regardless of whether or not they are infected with HIV. Little data exists on the nutritional status of drug users (with or without HIV infection) in India.

Methods

We describe and compare the nutrition and metabolic status of 107 HIV-positive and 193 HIV-negative male clients of a community-based drop-in center for injection drug users in Chennai, India. Measures of nutrition and metabolic status include body composition, dietary intake, food insecurity, and serum lipid levels.

Results

We found poor overall nutritional status in both the HIV-positive and HIV-negative clients, with HIV-positive men faring worse on some parameters. Both groups had extremely low percent body fat, but levels in HIV-positive participants were significantly lower (6.5% versus 7.9%, p = .01). HIV-positive men also had significantly lower total caloric and fat intakes compared to HIV-negative men. A considerable proportion (70%) of both HIV-positive and HIV-negative drug users were food insecure. HDL cholesterol levels were significantly lower and below normal range in the HIV-positive compared to HIV-negative men.

Conclusions

The high levels of food insecurity and poor nutritional status in this population, regardless of HIV status, indicates critical need for intervention. Improving nutritional status in those who are infected with HIV prior to initiation of antiretroviral treatment may help patients to reap the full benefits of therapy.     

Cigarette smoking status in pathological gamblers: association with impulsivity and cognitive flexibility

Background

While the majority of pathological gamblers are current cigarette smokers (CS), some have quit smoking (former smokers, FS) while others never smoked (never smokers, NS). The reasons for elevated smoking rates in pathological gambling are not known, but gamblers may use nicotine as a putative cognitive enhancer. This study evaluated impulsivity and cognitive flexibility in a sample of pathological gamblers with differing smoking status.

Methods

Fifty-five subjects with pathological gambling (CS, n = 34; FS, n = 10; NS, n = 11) underwent cognitive assessments using the Stop-Signal (SST) and Intradimensional/Extra-dimensional (ID/ED) set-shift tasks.

Results

CS reported less severe gambling problems than either FS or NS on the Yale Brown Obsessive Compulsive Scale modified for Pathological Gambling, and CS was associated with significantly fewer directional errors on the SST task, compared to NS. In addition, in CS, higher daily cigarette consumption was associated with fewer total errors on the ID/ED task.

Conclusions

The potential role of nicotine as a cognitive enhancer was supported by objective tests of impulsivity and cognitive flexibility. Human laboratory studies using nicotine challenges in pathological gambling will shed further light on this relationship.     

Validation of the Cannabis Expectancy Questionnaire (CEQ) in adult cannabis users in treatment

Background

Outcome expectancies are a key cognitive construct in the etiology, assessment and treatment of Substance Use Disorders. There is a research and clinical need for a cannabis expectancy measure validated in a clinical sample of cannabis users.

Method

The Cannabis Expectancy Questionnaire (CEQ) was subjected to exploratory (n = 501, mean age 27.45, 78% male) and confirmatory (n = 505, mean age 27.69, 78% male) factor analysis in two separate samples of cannabis users attending an outpatient cannabis treatment program. Weekly cannabis consumption was clinically assessed and patients completed the Severity of Dependence Scale-Cannabis (SDS-C) and the General Health Questionnaire (GHQ-28).

Results

Two factors representing Negative Cannabis Expectancies and Positive Cannabis Expectancies were identified. These provided a robust statistical and conceptual fit for the data. Internal reliabilities were high. Negative expectancies were associated with greater dependence severity (as measured by the SDS) and positive expectancies with higher consumption. The interaction of positive and negative expectancies was consistently significantly associated with self-reported functioning across all four GHQ-28 scales (Somatic Concerns, Anxiety, Social Dysfunction and Depression). Specifically, within the context of high positive cannabis expectancy, higher negative expectancy was predictive of more impaired functioning. By contrast, within the context of low positive cannabis expectancy, higher negative expectancy was predictive of better functioning.

Conclusions

The CEQ is the first cannabis expectancy measure to be validated in a sample of cannabis users in treatment. Negative and positive cannabis expectancy domains were uniquely associated with consumption, dependence severity and self-reported mental health functioning.     

Results of a pilot randomized controlled trial of buprenorphine for opioid dependent women in the criminal justice system

Aims

Recent studies have demonstrated the efficacy of both methadone and buprenorphine when used with opioid dependent men transitioning from prison to the community, but no studies have been conducted with women in the criminal justice (CJ) system. The aim of this study was to determine the efficacy of buprenorphine for relapse prevention among opioid dependent women in the CJ system transitioning back to the community.

Methods

36 women under CJ supervision were recruited from an inpatient drug treatment facility that treats CJ individuals returning back to the community. Nine were enrolled in an open label buprenorphine arm then 27 were randomized to buprenorphine (n = 15) or placebo (n = 12; double-blind). All women completed baseline measures and started study medication prior to release. Participants were followed weekly, provided urine drug screens (UDS), received study medication for 12 weeks, and returned for a 3-month follow-up. Intent-to-treat analyses were performed for all time points through 3 month follow-up.

Results

The majority of participants were Caucasian (88.9%), young (M ± SD = 31.8 ± 8.4 years), divorced/separated (59.2%) women with at least a high school/GED education (M ± SD = 12 ± 1.7 years). GEE analyses showed that buprenorphine was efficacious in maintaining abstinence across time compared to placebo. At end of treatment, 92% of placebo and 33% of active medication participants were positive for opiates on urine drug screen (Chi-Square = 10.9, df = 1; p < 0.001). However, by the three month follow-up point, no differences were found between the two groups, with 83% of participants at follow-up positive for opiates.

Conclusions

Women in the CJ system who received buprenorphine prior to release from a treatment facility had fewer opiate positive UDS through the 12 weeks of treatment compared to women receiving placebo. Initiating buprenorphine in a controlled environment prior to release appears to be a viable strategy to reduce opiate use when transitioning back to the community.     

The needle and the damage done: clinical and behavioural markers of severe femoral vein damage among groin injectors

Aim

To identify factors associated with severe femoral vein (FV) damage among groin injectors (GIs) on oral opioid substitution treatment.

Design

A cohort study.

Setting

Drug treatment centres in South East England.

Participants

GIs attending an ultrasound ‘health-check’ clinic.

Measures

Femoral ultrasonography and clinical grading of venous disease in each leg.

Method

Comparison of 67 GIs with severely damaged FV and 86 GIs with minimal/moderate damage.

Findings

The majority were men (69.3%) and the mean age was 36.2 years with mean duration of injecting drug use (IDU) of 13.3 years. There were no significant between-group differences in age, gender or duration of IDU. Severe FV damage was associated with longer duration of groin injecting (GI; P < 0.005), use of thick needles (blue-hub, 23G; or green-hub, 21G; P < 0.001), benzodiazepine injection (P < 0.005), history of deep vein thrombosis (DVT, P < 0.001) and recurrent DVT (P < 0.001), presence of depressed groin scar (P < 0.001) and chronic venous disease (CVD, P < 0.001). Logistic regression analysis revealed needle size (β 1.2, Wald 4.9, P < 0.05) and DVT (β 3.3, Wald 38.5, P < 0.001) as the main predictors of severe FV damage.

Conclusion

Needle and syringe exchange services should consider only supplying appropriate lengths of orange-hub needle (25G) on request from GIs. Early cessation of GI, avoidance of benzodiazepine injection and prompt diagnosis and treatment of DVT might also reduce the prevalence of severe FV damage among GIs and the associated healthcare burden. Routine examination of injecting sites among these patients should include an assessment of severity of venous disease in each leg.     

Oral and transdermal DL-methylphenidate-ethanol interactions in C57BL/6J mice: potentiation of locomotor activity with oral delivery

Purpose

Many abusers of dl-methylphenidate co-abuse ethanol. The present animal study examined behavioral effects of oral or transdermal dl-methylphenidate in combination with a high, depressive dose of ethanol to model co-abuse.

Methods

Locomotor activity of C57BL/6J mice was recorded for 3 h following dosing with either oral dl-methylphenidate (7.5 mg/kg) or transdermal dl-methylphenidate (Daytrana®;1/4 of a 12.5 cm² patch; mean dose 7.5 mg/kg), with or without oral ethanol (3 g/kg). Brains were enantiospecifically analyzed for the isomers of methylphenidate and the transesterification metabolite ethylphenidate.

Results

An otherwise depressive dose of ethanol significantly potentiated oral dl-methylphenidate induced increases in total distance traveled for the first 100 min (p < 0.05). Transdermal dl-methylphenidate increased total distance traveled after a latency of 80 min, though this effect was not potentiated by concomitant ethanol. Mean 3 h brain d-methylphenidate concentrations were significantly elevated by ethanol in both the oral (65% increase) and transdermal (88% increase) groups. The corresponding l-ethylphenidate concentrations were 10 ng/g and 130 ng/g.

Conclusions

Stimulant induced motor activity in rodents may correlate with abuse liability. Potentiation of dl-methylphenidate motor effects by concomitant ethanol carries implications regarding increased abuse potential of dl-methylphenidate when combined with ethanol.     

Prenatal exposure to bisphenol A and phthalates and infant neurobehavior

Objective

To examine the association of prenatal exposure to bisphenol A and select common phthalates with infant neurobehavior measured at 5 weeks.

Methods

We compared the concentration of maternal urinary metabolites of bisphenol A and phthalates at two distinct time points in pregnancy (16w, 26w) with scores on the NICU Network Neurobehavioral Scale (NNNS) at 5 weeks of age in a cohort of 350 mother/infant pairs.

Results

Prenatal exposure to BPA was not significantly associated with neurobehavioral outcomes at 5 weeks. Significant associations between prenatal exposure to measured phthalates and infant neurobehavioral outcomes differed by type of phthalate and were only seen with exposure measured at 26 weeks. Higher total di-butyl phthalate (DBP) metabolites at 26w were associated with improved behavioral organization evidenced by decreased arousal (p = .04), increased self-regulation (p = .052), and decreased handling (p = .02). In males, higher total di-2-ethylhexyl phthalate (DEHP) metabolites at 26w were associated with more nonoptimal reflexes (p = .02).

Conclusion

The association between prenatal phthalate exposure and infant neurobehavior differed by type of phthalate and was evident only with exposure measured at 26w. Prenatal exposure to DBP was associated with improved behavioral organization in 5-week-old infants. Prenatal exposure to DEHP was associated with nonoptimal reflexes in male infants. There was no evidence of an association between prenatal BPA exposure and infant neurobehavior.