Serum brain-derived neurotrophic factor level and its relation with cannabis use disorder and schizophrenia: A cross-sectional exploratory study in patients at a tertiary care hospital

BACKGROUND

Brain-derived neurotrophic factor (BDNF) has considerable relevance in neural growth and differentiation. It has been evaluated as a biomarker for individuals with various psychiatric disorders such as substance-related disorders and psychotic disorders.

OBJECTIVE

The present study explored differences in the levels of BDNF (in serum) among subjects using cannabis (with and without schizophrenia).

METHODS

This cross-sectional observational study compared the serum BDNF level in male subjects aged 18-45 years. Four groups of 20 subjects each were included: individuals with tobacco use disorder only, patients having schizophrenia, patients with cannabis use disorder, and finally patients with comorbid cannabis use disorder and schizophrenia.

RESULTS

The BDNF levels were found to be significantly different across the four groups. The BDNF levels in subjects with concurrent schizophrenia and cannabis use disorder were higher than each of the other three groups (cannabis use disorder, schizophrenia, and tobacco use disorder only).

CONCLUSION

We find that BDNF may be higher when cannabis use disorder and schizophrenia co-occur, as compared to either of the conditions alone. The findings should be interpreted with caution due to the low sample size and potential confounders.

Marijuana use is associated with hypersensitivity to multiple allergens in US adults

BACKGROUND

The recent legalization of marijuana use for both medical and recreational purposes in several states of the United Sates is expected to further increase the already high prevalence of marijuana use. Although allergic reactions are uncommon, the potential of marijuana use and cultivation to cause allergy should be considered. We aimed to investigate whether marijuana use is associated with the prevalence of sensitization to specific allergens.

METHODS

A total of 2671 adults (aged 20-59 years) who participated in the 2005-2006 National Health and Nutrition Examination Survey were included. Participants completed a questionnaire on marijuana use and underwent sensitization tests to 19 specific allergens. Those who reported marijuana use for at least 1 day in the past 30 days were considered marijuana users.

RESULTS

No difference was found in the history of allergy between marijuana users and non-users. Compared with marijuana non-users as a reference group, the adjusted odds ratio (AOR) of sensitization to a specific allergen among marijuana users was significantly greater for antibodies against the following: Alternaria alternata (AOR=1.67; 95% confidence interval (CI), 1.04-2.70), D. farinae (AOR=1.68; 95% CI, 1.27-2.22), D. pteronyssin (AOR=1.65; 95% CI, 1.32-2.06), ragweed (AOR=1.84; 95% CI, 1.30-2.59), rye grass (AOR=1.49; 95% CI, 1.12-1.97), Bermuda grass (AOR=1.55; 95% CI, 1.03-2.33), oak (AOR=1.76; 95% CI, 1.14-2.70), birch (AOR=2.09; 95% CI, 1.23-3.55), peanut (AOR=1.91; 95% CI, 1.25-2.92), and cat dander (AOR=1.51; 95% CI=1.13-2.03).

CONCLUSIONS

We provide preliminary findings to suggest that marijuana use is associated with sensitization to specific allergens, including molds, dust mites, plants, and cat dander.

THC and CBD in blood samples and seizures in Norway: Does CBD affect THC-induced impairment in apprehended subjects?

BACKGROUND AND AIMS

Several publications have suggested increasing cannabis potency over the last decade, which, together with lower amounts of cannabidiol (CBD), could contribute to an increase in adverse effects after cannabis smoking. Naturalistic studies on tetrahydrocannabinol (THC) and CBD in blood samples are, however, missing. This study aimed to investigate the relationship between THC- and CBD concentrations in blood samples among cannabis users, and to compare cannabinoid concentrations with the outcome of a clinical test of impairment (CTI) and between traffic accidents and non-accident driving under the influence of drugs (DUID)-cases. Assessment of THC- and CBD contents in cannabis seizures was also included.

METHODS

THC- and CBD concentrations in blood samples from subjects apprehended in Norway from April 2013-April 2015 were included (n=6134). A CTI result was compared with analytical findings in cases where only THC and/or CBD were detected (n=705). THC- and CBD content was measured in 41 cannabis seizures.

RESULTS

Among THC-positive blood samples, 76% also tested positive for CBD. There was a strong correlation between THC- and CBD concentrations in blood samples (Pearson's r=0.714, p<0.0005). Subjects judged as impaired by a CTI had significantly higher THC- (p<0.001) and CBD (p=0.008) concentrations compared with not impaired subjects, but after multivariate analyses, impairment could only be related to THC concentration (p=0.004). Analyzing seizures revealed THC/CBD ratios of 2:1 for hashish and 200:1 for marijuana.

CONCLUSIONS

More than ¾ of the blood samples testing positive for THC, among subjects apprehended in Norway, also tested positive for CBD, suggesting frequent consumption of high CBD cannabis products. The simultaneous presence of CBD in blood does, however, not appear to affect THC-induced impairment on a CTI. Seizure sample analysis did not reveal high potency cannabis products, and while CBD content appeared high in hashish, it was almost absent in marijuana.

Marijuana Use Is Associated with Behavioral Approach and Depressive Symptoms in Adolescents and Emerging Adults

BACKGROUND

Repeated CB1 binding due to THC results in downregulation of the endocannabinoid system in cortex and limbic regions, perhaps disrupting frontolimbic functioning. This is particularly a concern in young adults who are still undergoing neurodevelopment in frontal and limbic regions. Such disruptions may be linked to increased depressive symptoms, anxiety symptoms, and executive dysfunction, and decreased behavioral approach.

OBJECTIVES

Here we examine the influence of young adult marijuana use on anxiety, depressive symptoms, behavioral approach, and executive dysfunction. The influence of alcohol and gender were also assessed.

METHODS

84 participants (42 MJ, 42 controls) aged 18-25 were balanced for gender (39 F). Exclusion criteria included: MRI contraindications, left handed, comorbid Axis-I disorders, major medical or neurologic disorders, prenatal issues, or prenatal alcohol/illicit drug exposure, or excessive other drug use. Participants completed the FrsBE, BIS/BAS, State-Trait Anxiety Inventory (State), and BDI-II. Multiple regressions were run to predict anxiety, depressive symptoms, behavioral approach, and executive dysfunction from MJ group status, past year alcohol use, gender, and MJ*gender interactions, controlling for cotinine and ecstasy.

RESULTS

MJ group predicted increased depressive symptoms (p =.049). Decreased fun-seeking (p =.04), reward response (p =.01), and BAS total (p =.01) were predicted by MJ group. Gender predicted decreased reward responsiveness in females (p =.049) and decreased BIS in females (p =.03). Female marijuana users had increased anxiety symptoms (p =.04) and increased disinhibition (p =.04). Increased cotinine predicted increased drive (p =.046), reward responsiveness (p =.008) and BAS Total (p =.02). Apathy and Executive Dysfunction were not predicted by any measures. All results had small effect sizes.

CONCLUSIONS/IMPORTANCE

Depressive symptoms were greater in MJ users, while behavioral approach was decreased. Cotinine levels predicted increased behavioral approach. Female MJ users also had greater anxiety and disinhibition. In sum, these findings suggest sub-clinical threshold deficits related to regular marijuana use that are indicative of a need to prevent marijuana use in adolescents and young adults.

Cannabis Hyperemesis Syndrome in the Emergency Department: How Can a Specialized Addiction Team Be Useful? A Pilot Study

BACKGROUND

Chronic cannabis users may experience cyclical episodes of nausea and vomiting and learned behavior of hot bathing. This clinical condition, known as cannabis hyperemesis syndrome, was first reported in 2004.

OBJECTIVE

Our aim was to promote early recognition of this syndrome in emergency departments (EDs) and to increase referral to addiction specialists.

METHODS

Cannabis abusers were admitted to the ED for vomiting or abdominal pain from June 1, 2014 to January 1, 2015 and diagnosed with cannabis hyperemesis syndrome by a specialized addiction team. Then, medical records were examined retrospectively.

RESULTS

Seven young adults were included. Their mean age was 24.7 years (range 17-39 years) and the majority were men (male-to-female ratio 1.2). Biological and toxicological blood samples were taken in all patients. Tetrahydrocannabinol blood level was measured in 4 patients, with a mean blood concentration of 11.6 ng/mL. Radiographic examination including abdominal computed tomography and brain imaging were negative, as was upper endoscopy. Five patients compulsively took hot baths in an attempt to decrease the symptoms. Treatment was symptomatic. Five patients have started follow-up with the specialized addiction team.

CONCLUSIONS

Cannabis hyperemesis syndrome is still under-diagnosed 10 years after it was first described. Physicians should be aware of this syndrome to avoid repeated hospitalizations or esophageal complications. Greater awareness should lead to prompt treatment and prevention of future recurrence through cannabis cessation. Addiction specialists, as well as medical toxicologists, are experts in the management of cannabis abusers and can help re-establish the role of medical care in this population in collaboration with emergency physicians.

Invited Commentary: The Association Between Marijuana Use and Male Reproductive Health

Approximately 15% of all couples are unable to conceive after a year and are labeled infertile. In recent years, increasing attention has been given to lifestyle factors that may impact fertility. In the United States, it is estimated that there are more than 17 million current users of marijuana with 4.6 million using marijuana almost daily. Although common, to date, little data exist on the impact of marijuana use on male fertility. In the current issue of the Journal, Gundersen et al. (Am J Epidemiol. 2015;182(6):473-481) provide data examining the relationship between marijuana use and semen quality from young men recruited out of the general Danish population. Men who reported daily marijuana use displayed significant lower sperm concentration and sperm counts compared with nonusers, while testosterone levels were higher. The current report provides important information for patients and providers regarding the negative association of marijuana use on semen quality. Although the benefit of marijuana cessation on recovery is uncertain, further study on the impact of marijuana use on male reproductive health is warranted as more states explore marijuana legalization.

Association Between Use of Marijuana and Male Reproductive Hormones and Semen Quality: A Study Among 1,215 Healthy Young Men

A total of 1,215 young Danish men aged 18-28 years were recruited between 2008 and 2012 when they attended a compulsory medical examination to determine their fitness for military service. The participants delivered a semen sample, had a blood sample drawn, and underwent a physical examination. They responded to questionnaires including information on marijuana and recreational drug use during the past 3 months (no use, use once per week or less, or use more than once per week). A total of 45% had smoked marijuana within the last 3 months. Regular marijuana smoking more than once per week was associated with a 28% (95% confidence interval (CI): -48, -1) lower sperm concentration and a 29% (95% CI: -46, -1) lower total sperm count after adjustment for confounders. The combined use of marijuana more than once per week and other recreational drugs reduced the sperm concentration by 52% (95% CI: -68, -27) and total sperm count by 55% (95% CI: -71, -31). Marijuana smokers had higher levels of testosterone within the same range as cigarette smokers. Our findings are of public interest as marijuana use is common and may be contributing to recent reports of poor semen quality.

Self-reported lifetime marijuana use and interleukin-6 levels in middle-aged African Americans

BACKGROUND

Research examining the relationship between marijuana and cytokine function has been well developed in the biochemical literature. However, scant literature exists regarding this relationship between inflammatory markers and marijuana use in public health or behavioral studies and is virtually nonexistent in non-neurologically compromised African American samples.

METHODS

The current study examined the differences in serum interleukin-6 (IL-6), a proinflammatory cytokine, between non-drug users (n=78), marijuana only users (n=46) and marijuana plus other drugs users (n=45) in a community-based sample of middle aged African Americans. Participants included 169 African American adults (50.30% female), with a mean age of 45.68 years (SD=11.72 years) from the Washington, DC metropolitan area. Serum was drawn upon entry into the study and the participants completed a demographic questionnaire, which included questions regarding drug use history.

RESULTS

After adjusting for demographic and physiological covariates, analysis of covariance revealed a significant difference between the three groups, F(2,158)=3.08, p=0.04). Post hoc analyses revealed lifetime marijuana only users had significantly lower IL-6 levels (M=2.20 pg/mL, SD=1.93) than their lifetime nonuser counterparts (M=3.73 pg/mL, SD=6.28). No other comparisons among the groups were statistically significantly different.

CONCLUSION

The current findings extend previous cellular and biochemical literature, which identifies an inverse association between IL-6 and marijuana use. Examining this relationship in the psychological and behavioral literature could be informative to the development of clinical interventions for inflammatory diseases.

Plasma cannabinoid concentrations during dronabinol pharmacotherapy for cannabis dependence

BACKGROUND

Recently, high-dose oral synthetic delta-9-tetrahydrocannabinol (THC) was shown to alleviate cannabis withdrawal symptoms. The present data describe cannabinoid pharmacokinetics in chronic, daily cannabis smokers who received high-dose oral THC pharmacotherapy and later a smoked cannabis challenge.

METHODS

Eleven daily cannabis smokers received 0, 30, 60, or 120 mg/d THC for four 5-day medication sessions, each separated by 9 days of ad libitum cannabis smoking. On the fifth day, participants were challenged with smoking one 5.9% THC cigarette. Plasma collected on the first and fifth days was quantified by two-dimensional gas chromatography mass spectrometer for THC, 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH). Linear ranges (ng/mL) were 0.5-100 for THC, 1-50 for 11-OH-THC, and 0.5-200 for THCCOOH.

RESULTS

During placebo dosing, THC, 11-OH-THC, and THCCOOH concentrations consistently decreased, whereas all cannabinoids increased dose dependently during active dronabinol administration. THC increase over time was not significant after any dose, 11-OH-THC increased significantly during the 60- and 120-mg/d doses, and THCCOOH increased significantly only during the 120-mg/d dose. THC, 11-OH-THC, and THCCOOH concentrations peaked within 0.25 hours after cannabis smoking, except after 120 mg/d THC when THCCOOH peaked 0.5 hours before smoking.

CONCLUSIONS

The significant withdrawal effects noted during placebo dronabinol administration were supported by significant plasma THC and 11-OH-THC concentration decreases. During active dronabinol dosing, significant dose-dependent increases in THC and 11-OH-THC concentrations support withdrawal symptom suppression. THC concentrations after cannabis smoking were only distinguishable from oral THC doses for 1 hour, too short a period to feasibly identify cannabis relapse. THCCOOH/THC ratios were higher 14 hours after overnight oral dronabinol abstinence but cannot distinguish oral THC dosing from the smoked cannabis intake.

Drug use disorder (DUD) questionnaire: scale development and validation

BACKGROUND

Despite the ample interest in the measurement of substance abuse and dependence, obtaining biological samples from participants as a means to validate a scale is considered time and cost intensive and is, subsequently, largely overlooked.

OBJECTIVES

To report the psychometric properties of the drug use disorder (DUD) questionnaire including oral fluid and blood sample screening indicators measuring the three most commonly used illicit substances--marijuana, cocaine, and extramedicinal painkillers.

SUBJECTS

Participants were a subset (N = 2,702) of the 2007 U.S. National Roadside Survey that was administered to daytime and nighttime weekend drivers in the 48 contiguous states to examine the prevalence of substance use and misuse.

MEASURES

Participants completed demographic and substance use questions as well as the DUD--a 12-item measure assessing substance abuse and dependence. Participants could potentially have completed the DUD three times for each of the three substances. Subscales of abuse and dependence were created using Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition Text Revision [DSM-IV-TR]) criteria of these diagnoses.

RESULTS

The DUD displayed adequate internal consistency on both subscales of substance abuse and dependence (Cronbach's α ranging from .71 to .84 and .83 to .92, respectively). The DUD also demonstrated construct validity in comparison to biological markers of each substance.

CONCLUSIONS

The DUD is a biologically validated instrument that is both easy to utilize and may have valuable implications as a research tool among both clinical and nonclinical populations.

[Variability of cannabinoid findings in blood]

Cannabis products have been administered for many centuries; today, cannabis is the most widely used illegal drug all over the world. Nevertheless, the interpretation of cannabis findings in blood with regard to consumption behaviour and/or estimating the elapsed time since the last cannabis use is still a very challenging task. A wide variation of pharmacokinetic parameters has been observed even in experimental studies. Different chemical structures of precursors, smoking dynamics, pyrolysis of phytocannabinoids and frequency of drug use affect the amount of THC absorbed. Polymorphic enzymes are involved in phase-I-metabolism of THC. Pharmacological effects of other cannabinoids or medication on the pharmacokinetics of THC have not yet been studied in detail. Hydrolysis of cannabis conjugates may occur during storage of blood samples and processing of specimens for analysis; knowledge on the stability of cannabinoids in forensic specimens is still poor. Whether determination of cannabinoid conjugates may be useful is a matter of further consideration. At present, the broad variation of pharmacokinetic parameters and the limiting factors discussed in the present paper should be taken into account when using data from experimental studies for interpretation of analytical results in forensic case work.

Chronic viral hepatitis is a significant contributor to the immunosenescent phenotype of parenteral drug addiction

Intravenous drug addiction is known to be associated with an inordinate morbidity and mortality. As our previous report had identified an immune phenotype consistent with accelerated ageing, we wished to investigate how much of this change may have been related to chronic viral hepatitis. A total of 12 409 clinical pathology results from the period 1995-2007 were reviewed. To control for the differences in age, only patients less than 48 years of age were considered. A total of 636 substance use disorder (SUD) and 6103 non-SUD (N-SUD) patients were studied. They had comparable ages (mean +/- SD 31.32 +/- 6.90 versus 31.57 +/- 9.23, P-value not significant), but the SUD group had more males (74.37% versus 53.20%, P < 0.001). For most of the changes examined splitting the two SUD groups into hepatitis C positive (HCV+) and hepatitis C negative (HCV-) demonstrated that the majority of the described changes were most marked in the HCV+ group. The globulins were higher in the HCV+ group and the albumin was lower and fell more markedly with age than in N-SUD or HCV- (all P < 0.001). The globulin/albumin ratio was significantly higher in HCV+ than HCV- or N-SUD (both P < 0.0001) and rose more with age. These changes were paralleled by the ESR, elevations in the CRP and lymphocyte count. Transaminases were elevated in SUD and HCV+ groups compared with N-SUD (all P < 0.02). At multivariate analysis ESR, lymphocyte count, dual hepatitis B and C seropositivity, AST and HCVAb were significant predictors of the serum globulin level and accounted for 21% of the variance. These data extend our earlier report and show that much of the immunosenescent phenotype of SUD, encompassing the known immunosuppression and the observed immunostimulation, is statistically related to chronic viral hepatitis. Important theoretical and practical management (vaccination) implications ensue.

N-acetylaspartate (NAA) correlates inversely with cannabis use in a frontal language processing region of neocortex in MDMA (Ecstasy) polydrug users: a 3 T magnetic resonance spectroscopy study

Impaired verbal memory is common in MDMA (Ecstasy) polydrug users. The contributions of Ecstasy or polydrug exposure to reduced verbal memory are unclear, as is the neural basis for this cognitive deficit. Ecstasy users have reduced gray matter in brain regions mediating verbal memory (BA 18, 21 and 45). N-acetylaspartate (NAA) as a neuronal marker and myoinositol (mI) as a glial marker are inconsistently affected in Ecstasy users. We used 3 T MRS in 17 recreational drug users to test the hypothesis that Ecstasy polydrug use would be associated with altered NAA or mI in BA 18, 21 and 45. No effects were seen for mI. Metabolite ratios for NAA (mean+/-SD) were: BA 18-NAA/Cr (2.030+/-0.188); BA 21-NAA/Cr (1.861+/-0.325); BA 45-NAA/Cr (1.925+/-0.329). Lifetime cannabis use was significantly associated with BA 45 NAA/Cr (r=-0.687, p=0.014) but not with NAA in BA 18 or 21. In contrast, there were no statistically significant associations for lifetime use of Ecstasy, alcohol, or cocaine with NAA. These findings suggest that cannabis use may contribute to altered neuronal integrity in Ecstasy polydrug users in a brain region associated with verbal memory processing.

Functional MRI of inhibitory processing in abstinent adolescent marijuana users

BACKGROUND

Marijuana intoxication appears to impair response inhibition, but it is unclear if impaired inhibition and associated brain abnormalities persist after prolonged abstinence among adolescent users. We hypothesized that brain activation during a go/no-go task would show persistent abnormalities in adolescent marijuana users after 28 days of abstinence.

METHODS

Adolescents with (n = 16) and without (n = 17) histories of marijuana use were compared on blood oxygen level dependent (BOLD) response to a go/no-go task during functional magnetic resonance imaging (fMRI) after 28 days of monitored abstinence. Participants had no neurological problems or Axis I diagnoses other than cannabis abuse/dependence.

RESULTS

Marijuana users did not differ from non-users on task performance but showed more BOLD response than non-users during inhibition trials in right dorsolateral prefrontal, bilateral medial frontal, bilateral inferior and superior parietal lobules, and right occipital gyri, as well as during "go" trials in right prefrontal, insular, and parietal cortices (p < 0.05, clusters > 943 microl). Differences remained significant even after controlling for lifetime and recent alcohol use.

CONCLUSIONS

Adolescent marijuana users relative to non-users showed increased brain processing effort during an inhibition task in the presence of similar task performance, even after 28 days of abstinence. Thus, increased brain processing effort to achieve inhibition may predate the onset of regular use or result from it. Future investigations will need to determine whether increased brain processing effort is associated with risk to use.

Adequate antipsychotic treatment normalizes serum nerve growth factor concentrations in schizophrenia with and without cannabis or additional substance abuse

Neurotrophins such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are important for the development and maintenance of neuron function. Neurodevelopment is thought to be impaired in schizophrenia, and vulnerable schizophrenic brains may be more sensitive to toxic influences. Thus, cannabis as a neurotoxin (and other substances) may be more harmful to schizophrenic brains than to non-schizophrenic brains, when used chronically. In a previous study we demonstrated an earlier disease onset and significantly higher serum NGF concentrations in drug-naïve schizophrenic patients with previous long-term cannabis abuse than in schizophrenics without cannabis abuse or cannabis abusers without schizophrenia. We therefore investigated whether this difference is still observed after treatment. Serum NGF measured in 114 treated schizophrenic patients (schizophrenia alone, n=66; schizophrenia plus cannabis abuse, n=42; schizophrenia plus multiple substance abuse, n=6) no longer differed significantly among those groups and from the control groups (healthy controls, n=51; cannabis controls, n=24; multiple substance controls, n=6). These results were confirmed by an additional prospective study in 28 patients suffering from schizophrenia (S) or schizophrenia with cannabis abuse (SC). Previously elevated serum NGF levels in the drug-naïve state, also differing between the groups (S: 83.44+/-265.25 pg/ml; SC: 246.89+/-310.24 pg/ml, S versus SC: p=0.03) dropped to 10.72+/-14.13 pg/ml (S) and 34.19+/-38.96 pg/ml (SC) (S versus SC, p>0.05), respectively, after adequate antipsychotic treatment. We thus conclude that antipsychotic treatment leads to recovery of neural integrity, as indicated by renormalized NGF values.

Review of Biologic Matrices (Urine, Blood, Hair) as Indicators of Recent or Ongoing Cannabis Use

Especially for cannabinoids, analytical procedures for the verification of recent use and generally for the assessment of the extent of drug abuse are of interest in clinical and forensic toxicology. For confirmation of abstinence, urine analysis seems to be a useful tool. Serial monitoring of THC-COOH to creatinine ratios can differentiate between recent drug use and residual THC-COOH excretion (THC-COOH/creatinine ratio > or = 0.5 compared with previous specimen ratio). For an assessment of the extent of cannabis use, the determination of free and bound THC-COOH and especially of THC and 11-OH-THC glucuronides are suggested as useful but need further confirmation. Blood analysis is preferred for the interpretation of acute effects after cannabis abuse. The cannabis influence factor (CIF) was demonstrated as a better tool to interpret the concentrations of THC and its metabolites in blood in forensic cases and therefore it was proposed to assume absolute driving inability because of cannabis intoxication from a CIF > or = 10. Additionally, a higher CIF is indicative of a recent cannabis abuse. Also discrimination between occasional use of cannabis and regular drug consumption is possible by analysis of THC-COOH in blood samples because of the long plasma half-life of THC-COOH and its accumulation in the blood of frequent cannabis consumers. In routine tests, blood samples have to be taken within a prescribed 8-day-period, and a THC-COOH concentration >75 ng/mL is assumed to be associated with regular consumption of cannabis products, whereas plasma THC-COOH concentrations <5 ng/mL are associated with occasional consumption. In contrast to other illicit drugs, hair analysis lacks the sensitivity to act as a detector for cannabinoids. THC and especially the main metabolite THC-COOH have a very low incorporation rate into hair and THC is not highly bound to melanin, resulting in much lower concentrations in hair compared with other drugs. Additionally, THC is present in cannabis smoke and also can be incorporated into the hair only by contamination. For the determination of the main metabolite THC-COOH in the picogram or femtogram per milligram range, which indicates an active consumption, special analytical procedures, such as GC/MS/MS techniques, are required.

[Schizophrenia and cannabis consumption: epidemiology and clinical symptoms]

More and more young people consume cannabis in sometimes high dosage at an age when their brain is not yet fully developed and reacts particularly sensitive to toxic influences. Cannabis can induce and exacerbate psychotic symptoms and it can deteriorate the disease process in schizophrenic patients. First-episode schizophrenic patients with long-term cannabis consumption were significantly younger at disease-onset, mostly male and suffered more often from paranoid schizophrenia (with a better prognosis) than those without cannabis consumption in our investigation. The significance of higher serum neurotrophin levels in cannabis consuming schizophrenics as compared to those without cannabis consumption remains equivocal so far. The cognitive functions of this patient group are at least not worse than in those with schizophrenia alone. Taken together, the effect of cannabis on the brain vulnerable to schizophrenia is not yet completely understood; besides the undoubtedly deleterious effects, there may also be some neuroprotective effects.

Cannabis intoxication and fatal road crashes in France: population based case-control study

OBJECTIVES

To evaluate the relative risk of being responsible for a fatal crash while driving under the influence of cannabis, the prevalence of such drivers within the driving population, and the corresponding share of fatal crashes.

DESIGN

Population based case-control study.

PARTICIPANTS

10 748 drivers, with known drug and alcohol concentrations, who were involved in fatal crashes in France from October 2001 to September 2003.

MAIN OUTCOME MEASURES

The cases were the 6766 drivers considered at fault in their crash; the controls were 3006 drivers selected from the 3982 other drivers. Positive detection of cannabis was defined as a blood concentration of Delta9tetrahydrocannabinol of over 1 ng/ml. The prevalence of positive drivers in the driving population was estimated by standardising controls on drivers not at fault who were involved in crashes resulting in slight injuries.

RESULTS

681 drivers were positive for cannabis (cases 8.8%, controls 2.8%), including 285 with an illegal blood alcohol concentration (> or = 0.5 g/l). Positive cannabis detection was associated with increased risk of responsibility (odds ratio 3.32, 95% confidence interval 2.63 to 4.18). A significant dose effect was identified; the odds ratio increased from 2.18 (1.22 to 3.89) if 0 < Delta9tetrahydrocannabinol < 1 ng/ml to 4.72 (3.04 to 7.33) if Delta9tetrahydrocannabinol > or = 5 ng/ml. The effect of cannabis remains significant after adjustment for different cofactors, including alcohol, with which no statistical interaction was observed. The prevalence of cannabis (2.9%) estimated for the driving population is similar to that for alcohol (2.7%). At least 2.5% (1.5% to 3.5%) of fatal crashes were estimated as being attributable to cannabis, compared with 28.6% for alcohol (26.8% to 30.5%).

CONCLUSIONS

Driving under the influence of cannabis increases the risk of involvement in a crash. However, in France its share in fatal crashes is significantly lower than that associated with positive blood alcohol concentration.

The relationship between performance on the standardised field sobriety tests, driving performance and the level of Δ9-tetrahydrocannabinol (THC) in blood

The consumption of Delta9-tetrahydrocannabinol (THC) as cannabis has been shown to result in impaired and culpable driving. Testing drivers for the presence of THC in blood is problematic as THC and its metabolites may remain in the blood for several days following its consumption, even though the drug may no longer have an influence on driving performance. In the present study, the aim was to assess whether performance on the standardised field sobriety tests (SFSTs) provides a sensitive measure of impaired driving behaviour following the consumption of THC. In a repeated measures design, 40 participants consumed cigarettes that contained either 0% THC (placebo), 1.74% THC (low dose) or 2.93% THC (high dose). For each condition, after smoking a cigarette, participants performed the SFSTs on three occasions (5, 55 and 105 min after the smoking procedure had been completed) as well as a simulated driving test on two occasions (30 and 80 min after the smoking procedure had been completed). The results revealed that driving performance was not significantly impaired 30 min after the consumption of THC but was significantly impaired 80 min after the consumption of THC in both the low and high dose conditions. The percentage of participants whose driving performance was correctly classified as either impaired or not impaired based on the SFSTs ranged between 65.8 and 76.3%, across the two THC conditions. The results suggest that performance on the SFSTs provides a moderate predictor of driving impairment following the consumption of THC and as such, the SFSTs may provide an appropriate screening tool for authorities that wish to assess the driving capabilities of individuals suspected of being under the influence of a drug other than alcohol.

Two cases of "cannabis acute psychosis" following the administration of oral cannabis

BACKGROUND

Cannabis is the most commonly used illegal drug and its therapeutic aspects have a growing interest. Short-term psychotic reactions have been described but not clearly with synthetic oral THC, especially in occasional users.

CASE PRESENTATIONS

We report two cases of healthy subjects who were occasional but regular cannabis users without psychiatric history who developed transient psychotic symptoms (depersonalization, paranoid feelings and derealisation) following oral administration of cannabis. In contrast to most other case reports where circumstances and blood concentrations are unknown, the two cases reported here happened under experimental conditions with all subjects negative for cannabis, opiates, amphetamines, cocaine, benzodiazepines and alcohol, and therefore the ingested dose, the time-events of effects on behavior and performance as well as the cannabinoid blood levels were documented.

CONCLUSION

While the oral route of administration achieves only limited blood concentrations, significant psychotic reactions may occur.

[Use of cannabis: screening strategy and evaluation of severity factors]

Cannabis consumption occupies a front place in the field of addictions in France, not only by the levels of consumption but also by the related health harms induced with a growing potentially problematic use of cannabis among young men (14% of those aged 14 to 18 in 2001). Therefore, it is not only an educational problem but also a public health issue. Harmful cannabis use must be systematically researched by history taking on the consumption of tobacco, alcohol and drugs as an integrated part of the patient's social history. The diagnostic of cannabis abuse is made by a clinical evaluation of harmful use, the frequency and quantity of consumption, the search for complications. The practitioner must also evaluate the factors of severity (modalities of consumption and parameters predictive of poor outcome like precocity of first experiences, auto-therapeutic use and the various types of individual and social vulnerability: personality characteristics, psychiatric pathology, family characteristics and social environment). The physician may also be helped by drug screening diagnostic and evaluation instruments like validated autoquestionnaires. Urinary screening can be used especially in public health or forensic medicine fields. Some situational risks must be known while cannabis intoxicated: pregnant women, mentally ill, driving, working. Finally, professionals must know that present situation is very different from what we knew in the seventies and that they have to cope with this fast moving issue.

Brain-derived neurotrophic factor serum concentrations are increased in drug-naive schizophrenic patients with chronic cannabis abuse and multiple substance abuse

Neurotrophins such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are critically implicated in development and maintenance of function of neurons. Neurodevelopment is reported to be impaired in schizophrenia and vulnerable schizophrenic brains may be more sensitive to toxic influences. Thus, cannabis as a neurotoxin, may be more harmful to schizophrenic brains than to non-schizophrenic brains when used chronically. And neurotoxic events may promote disease-onset and lead to exaggerated release of neurotrophins. We investigated 157 drug-naive first-episode schizophrenic patients and found significantly elevated BDNF serum concentrations (by up to 34%) in patients with chronic cannabis abuse (n = 35, p < 0.001) or multiple substance abuse (n = 20, p < 0.001) prior to disease onset. Drug-naive schizophrenic patients without cannabis consumption showed similar results to normal controls and cannabis controls without schizophrenia. Thus, raised BDNF serum levels are not related to schizophrenia and/or substance abuse itself but may reflect a cannabis-related idiosyncratic damage of the schizophrenic brain. In line with this hypothesis, disease onset was 5.2 years earlier in the cannabis-consuming group (p = 0.0111).

Drugs and driving: the Finnish perspective

Drugs can cause behavioural impairment of the driver's ability to operate safely That impairment of driving ability can be documented, and biological fluids can be tested for drugs. Most countries have legislation that covers driving under the influence of alcohol and/or drugs. Some countries have introduced zero-tolerance laws (per se laws), which prohibit the operation of a motor vehicle while an illicit drug or its metabolite is present in the body, whether or not impairment is manifested. There is growing interest in using saliva (oral fluid) in preliminary roadside testing. Legislation in the state of Victoria, Australia, already allows the use of oral fluid for evidentiary testing in the case of cannabis and methamphetamine. Nevertheless, blood testing will probably remain the most common form of evidentiary testing. It has been estimated that the prevalence of illicit drug use among the general driving population in Europe is in the range of 1-5 per cent, while the prevalence of licit drugs, such as benzodiazepines, affecting driving performance is higher: 5-10 per cent. Epidemiological research is often carried out on offenders and drivers involved in collisions. Among drivers suspected of driving under the influence of drugs, there is a high percentage of licit and/or illicit drug use, as the statistics for Finland in the present article show. The drugs of most concern are amphetamine and amphetamine-type substances, cocaine, cannabis, opiates and benzodiazepines and other sedative-hypnotics. The handling of drugs and driving cases are presented, and a summary of areas for further study are provided.

Chronic cannabis abuse raises nerve growth factor serum concentrations in drug-naive schizophrenic patients

Long-term cannabis abuse may increase the risk of schizophrenia. Nerve growth factor (NGF) is a pleiotropic neurotrophic protein that is implicated in development, protection and regeneration of NFG-sensitive neurones. We tested the hypothesis that damage to neuronal cells in schizophrenia is precipitated by the consumption of cannabis and other neurotoxic substances, resulting in raised NGF serum concentrations and a younger age for disease onset. The NGF serum levels of 109 consecutive drug-naive schizophrenic patients were measured and compared with those of healthy controls. The results were correlated with the long-term intake of cannabis and other illegal drugs. Mean (+/- SD) NGF serum levels of 61 control persons (33.1 +/- 31.0 pg/ml) and 76 schizophrenics who did not consume illegal drugs (26.3 +/- 19.5 pg/ml) did not differ significantly. Schizophrenic patients with regular cannabis intake (> 0.5 g on average per day for at least 2 years) had significantly raised NGF serum levels of 412.9 +/- 288.4 pg/ml (n = 21) compared to controls and schizophrenic patients not consuming cannabis (p < 0.001). In schizophrenic patients who abused not only cannabis, but also additional substances, NGF concentrations were as high as 2336.2 +/- 1711.4 pg/ml (n = 12). On average, heavy cannabis consumers suffered their first episode of schizophrenia 3.5 years (n = 21) earlier than schizophrenic patients who abstained from cannabis. These results indicate that cannabis is a possible risk factor for the development of schizophrenia. This might be reflected in the raised NGF-serum concentrations when both schizophrenia and long-term cannabis abuse prevail.

Auditory-evoked potentials and selective attention: different ways of information processing in cannabis users and controls

The present study tested the hypothesis that chronic cannabis use leads to persistent attentional dysfunctions and that age of onset of cannabis use is a potential predictor of impaired test performance and information processing. Brain event-related potentials (ERPs) during a complex auditory selective attention task were recorded from 21 cannabis users divided into two groups according to age of onset and from 13 controls comparable with respect to age, IQ and educational background. Participants were instructed to detect target tones of a particular location, pitch and duration from a total sample of random frequencies. The study reveals that the latency of the greatest negative peak of ERPs (200 and 300 ms) to target tones was shorter in controls, while there was no clear difference between target and non-target within cannabis users. In addition, users displayed a reduced P3 to target tones. This was more pronounced in early-onset cannabis users. These data suggest that chronic cannabis use relates to different types of information processing under conditions of selective attention. There is some evidence that users employed different strategies of attention allocation. The results are discussed with respect to possible underlying mechanisms and clinical implications.

[Postmortem detection of hemp intoxication]

The diagnostic tools applicable to the forensic medical expertise of cadavers in cannabinoid intoxication (CI) were evaluated. Histochemistry with incubation of stable blue "B" (SBB) were used for the detection of cannabinoids in the bronchi and lungs. Hyperemia and capillarostasis in the mucous tunics of the mouth and stomach as well as hyperemia and edema in the lungs and brain were histochemically detected in CI. The histochemical activity of aldehyde dehydrogenase (AlDG) was most essentially decreasing in the adrenal glands and brain of younger persons. The SBB reaction in the bronchial and alveolar epithelia was positive in 85% of cases. A high proof value of the CI diagnostics was pointed out in cadaver expertise.

Platelet adenylyl cyclase activity as a state or trait marker in alcohol dependence: results of the WHO/ISBRA Study on State and Trait Markers of Alcohol Use and Dependence

BACKGROUND

There has been considerable interest in identifying biochemical markers indicative of a genetic predisposition to alcohol dependence ("trait markers"), as well as biochemical markers of recent alcohol drinking ("state markers"). Platelet adenylyl cyclase activity has been suggested as a trait and/or as a state marker related to alcohol dependence. We have now measured platelet adenylyl cyclase activity in more than 1400 well-characterized subjects, which allows us to investigate the influence of a broad range of factors on this activity.

METHODS

Subjects were recruited as part of the WHO/ISBRA Study on State and Trait Markers of Alcohol Use and Dependence and were interviewed by using the WHO/ISBRA Interview Schedule. Adenylyl cyclase activity (basal, cesium fluoride [CsF]-, forskolin- and Gpp(NH)p-stimulated activities) was measured in platelet samples that were obtained at the time of interview. Data were analyzed by multivariate regression analyses.

RESULTS

The multivariate analyses revealed that recent abstinence from alcohol was associated with diminutions in platelet adenylyl cyclase activities. A positive family history of alcohol dependence was associated with higher levels of adenylyl cyclase activities, and there was a significant interaction between the effect of alcohol consumption in the past month and family history of alcohol dependence; that is, the influence of alcohol consumption depended on whether the individual had a positive family history. A history of marijuana abuse also was associated with higher levels of platelet adenylyl cyclase activities, and a history of major depression was associated with lower levels of forskolin- and CsF-stimulated activities. Sex, race, and site of recruitment also affected some adenylyl cyclase activities, but there was no significant association of alcohol dependence or abuse with any of the platelet adenylyl cyclase activities.

DISCUSSION

The large population and extensive characterization of subjects in this study provided an advantage over previous studies in which only the association of a few individual factors with adenylyl cyclase activity was investigated. The results demonstrate that although platelet adenylyl cyclase activity could be useful as a trait marker of alcohol dependence, its reliability in this regard is diminished by the influence of recent alcohol drinking and other variables. The associations between platelet adenylyl cyclase activities and marijuana abuse, as well as a history of depression, suggest that it may be worthwhile to study the genetic association of adenylyl cyclases (e.g., polymorphisms in the genes that code for particular adenylyl cyclase isoforms) with a predisposition to depression as well as to alcohol or marijuana abuse/dependence.

Bloodborne sexually transmitted infections in patients presenting for substance abuse treatment in Jamaica

BACKGROUND

Substance use, including alcohol and illicit drugs, increases the risk for the acquisition and transmission of sexually transmitted infection (STI).

GOAL

To determine the prevalence of bloodborne STI including HIV, human T-cell lymphotrophic virus type 1, hepatitis B virus, and syphilis in residents of a detoxification and rehabilitation unit in Jamaica.

STUDY DESIGN

The demographic characteristics and the results of laboratory investigations for STI in 301 substance abusers presenting during a 5-year period were reviewed. The laboratory results were compared with those of 131 blood donors.

RESULTS

The substances used by participants were alcohol, cannabis, and cocaine. None of the clients was an IV drug user. Female substance abusers were at higher risk for STI. The prevalence of STI in substance abusers did not differ significantly from that in blood donors (12% versus 10%); however, the prevalence of syphilis in substance abusers was significantly higher than that in blood donors (6% versus 3%, P < 0.05). The prevalence of syphilis was dramatically increased in female substance abusers and female blood donors (30%, P < 0.001 and 13%, P < 0.05, respectively). An excess of human T-cell lymphotrophic virus type 1 was also observed in female compared with male substance abusers. Unemployment was identified also as a risk factor for sexually transmitted disease in substance abusers.

CONCLUSION

The results endorsed the policy of screening detoxification clients for STI and indicate a need for gender-specific approaches to the control of substance abuse and STI in Jamaica.

[Cannabis and automobile driving]

Cannabis use has increased considerably during the last 15 years. One of the major problems dealing with cannabis use is driving under the influence of drugs. With the exception of ethyl alcohol, the majority of the epidemiological studies have shown that cannabis is the most frequently detected substance in people suspected of driving under the influence of drugs. Experimental studies are therefore needed to assess cannabis effects on driving capability. Many studies indicate that cannabis impairs psychomotor performance. This impairment becomes obvious when high doses of cannabis are taken, when ethyl alcohol or other drugs are simultaneously ingested, or when sustained attention is needed. Moreover, cannabis effects are qualitatively different from those observed after ethyl alcohol consumption. In forensic practice, cannabis impairment of driving performance must be related to cannabinoids blood concentrations. To facilitate the interpretation of cannabinoids blood levels, several models were set up recently. These models must be further improved in order to fit in with all circumstances of cannabis use.

Dietary intake and nutritional status of US adult marijuana users: results from the Third National Health and Nutrition Examination Survey

OBJECTIVES

This study examined dietary intakes and nutritional status of marijuana users and non-current marijuana users in US adults aged 20 to 59 years.

METHODS

We used data from the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994. Information on self-reported drug use, including marijuana, was obtained as part of the NHANES III physical examination component. Nutritional status was assessed using height and weight, and blood biochemistries. Dietary intake was assessed using a 24-hour recall and a food-frequency questionnaire.

RESULTS

Among adults 20-59 years of age, 45% reported ever having used marijuana in their lifetime. A total of 8.7% reported using marijuana in the past month. Current marijuana users had higher intakes of energy and nutrients than non-current marijuana users; however, body mass index (BMI) was slightly lower. We found higher cigarette-smoking rates and higher consumption of sodas and alcohol, specifically beer, among marijuana users than among non-current marijuana users. Marijuana users also consumed more sodium, fewer fruits, and more pork, cheese, and salty snacks. Nutritional status, using indicators of serum nutrients, serum albumin, haematocrit and haemoglobin, was similar between marijuana users and non-current marijuana users. Serum carotenoid levels were lower among marijuana users, independent of cigarette smoking.

CONCLUSION

Dietary intake was different among marijuana users than among non-current marijuana users. Although overall nutritional status was similar, serum carotenoid levels were lower in marijuana users. The long-term health effects of these differences in marijuana users deserve careful consideration in future research.

Blockade of effects of smoked marijuana by the CB1-selective cannabinoid receptor antagonist SR141716

BACKGROUND

SR141716, a recently developed CB1 cannabinoid receptor antagonist, blocks acute effects of Delta-9-tetrahydrocannabinol (THC) and other CB1 cannabinoid agonists in vitro and in animals. These findings suggest that CB1 receptors mediate many of the effects of marijuana, but this has not been evaluated in humans.

METHODS

Sixty-three healthy men with a history of marijuana use were randomly assigned to receive oral SR141716 or a placebo in an escalating dose (1, 3, 10, 30, and 90 mg) design. Each subject smoked an active (2.64% THC) or placebo marijuana cigarette 2 hours later. Psychological effects associated with marijuana intoxication and heart rate were measured before and after antagonist and marijuana administration.

RESULTS

Single oral doses of SR141716 produced a significant dose-dependent blockade of marijuana-induced subjective intoxication and tachycardia. The 90-mg dose produced 38% to 43% reductions in visual analog scale ratings of "How high do you feel now?" "How stoned on marijuana are you now?" and "How strong is the drug effect you feel now?" and produced a 59% reduction in heart rate. SR141716 alone produced no significant physiological or psychological effects and did not affect peak THC plasma concentration or the area under the time x concentration curve. SR141716 was well tolerated by all subjects.

CONCLUSIONS

SR141716 blocked acute psychological and physiological effects of smoked marijuana without altering THC pharmacokinetics. These findings confirm, for the first time in humans, the central role of CB1 receptors in mediating the effects of marijuana.

The prevalence of alcohol, cannabinoids, benzodiazepines and stimulants amongst injured drivers and their role in driver culpability: part ii: the relationship between drug prevalence and drug concentration, and driver culpability

Blood samples from 2,500 injured drivers were analysed for alcohol, cannabinoids (measured by the presence of THC), benzodiazepines and stimulants. The relationship between the prevalence and concentration of drugs and the culpability of the driver was examined using an objective method for assessing culpability. There were no significant differences between males and females with respect to culpability. However, there was a relationship between age and culpability: drivers under 26 years and over 60 years were more likely to be culpable. Drivers who tested positive for alcohol only, benzodiazepines only and the combinations of alcohol and THC and alcohol and benzodiazepines were significantly more likely to be culpable for the crash compared with the drug-free group. Conversely, a lower percentage of drivers who only tested positive for THC were culpable for the crash compared with drug-free drivers. This difference was not statistically significant. For car drivers in single-vehicle crashes, the majority of drivers were judged culpable irrespective of drug use. In multiple-vehicle crashes, car drivers testing positive for alcohol only or benzodiazepines only were more likely to be culpable for the crash compared with drug-free drivers. For motorcycle riders in both single- and multiple-vehicle crashes, there were no significant differences between the drug-positive and drug-free groups. A higher percentage of drug-free riders in multiple-vehicle crashes were culpable compared with riders who only tested positive for THC, but this difference was not statistically significant. There was a significant concentration-dependent relationship between alcohol and culpability: as blood alcohol concentration increased, so did the percentage of culpable drivers. When THC was used alone, there was no significant increase in culpability. For those drivers with benzodiazepines at therapeutic concentrations and above, there was a significant increase in culpability. The relationship between stimulants and culpability was not significant, although a higher proportion of stimulant-positive drivers were culpable compared with drug-free drivers. The combinations of alcohol and THC, and alcohol and benzodiazepines also produced a significant increase in culpability, but this increase was not significantly greater than that produced by alcohol alone.

Platelet dense granule secretion and aggregation in adolescents with conduct disorder: effects of marijuana use

BACKGROUND

We had previously reported a decrease in agonist-induced platelet dense granule secretion in blood samples from male adolescents with and without Conduct Disorder (CD). In an augmented sample, we have now employed multivariate modeling to examine the simultaneous effects of CD and regular monthly alcohol and marijuana use on both the dense granule secretion and aggregation phases of agonist-induced platelet responses.

METHODS

Blood samples were obtained from adolescents with and without a CD diagnosis. Platelet dense granule secretion and aggregation responses to a variety of agonists were examined in the laboratory.

RESULTS

Significant multivariate interactions of CD status with regular marijuana use were found for responses to collagen, ADP alone, and ADP plus 0.2 microgram. of serotonin. Responses in platelets from youth with CD, but without regular marijuana use differed from other subjects. Multivariate main effects of marijuana use alone on platelet responses to arachidonic acid and ADP plus 1.0 microgram. of serotonin were found. No effects of alcohol use were found.

CONCLUSIONS

The results demonstrate an interaction between CD and the effects of chronic marijuana use for several agonists in this platelet model system, and further support the possibility of a variation in signal transduction mechanisms in CD.

GC-MS-MS confirmation of unusually high delta 9-tetrahydrocannabinol levels in two postmortem blood samples

Unusually high levels of delta 9-tetrahydrocannabinol (delta 9-THC) were detected in two postmortem blood samples. Because of sample decomposition, the major metabolite, 11-nor-9-carboxy-tetrahydrocannabinol (delta 9-THCCOOH), could not be determined using the routine EI-MS technique, which cast some doubt on the delta 9-THC result. Analysis of the sample extracts by GC-MS-MS confirmed the presence of delta 9-THC, although no delta 9-THCCOOH was detected.

The effect of drug exposure on thyroid hormone levels of newborns

This study examines the effect of women's alcohol abuse during pregnancy on the thyroid-stimulating hormone (TSH) and thyroxine (T4) levels of their babies at birth. Forty-seven babies were born to mothers identified as substance abusers. Maternal use of marijuana and/or cocaine did not result in newborns' TSH and T4 hormone levels being significantly different from non-substance-abusing controls' TSH and T4 levels. Alcohol use, however, was significantly linked to lower newborn TSH levels, lower than TSH levels of a control sample of newborns whose mothers used marijuana and/or cocaine, and lower than a control sample of newborns whose mothers abused no substances. This finding suggests further investigation of possible links between thyroid functioning and fetal alcohol syndrome (FAS).

Effects of chronic marijuana use on testosterone, luteinizing hormone, follicle stimulating hormone, prolactin and cortisol in men and women

To investigate possible effects of chronic marijuana use on reproductive and stress hormones, we assayed testosterone, luteinizing hormone, follicle stimulating hormone, prolactin, and cortisol in 93 men and 56 women with a mean (+/- S.E.) age of 23.5 +/- 0.4 years. Hormone values were compared among groups of subjects stratified according to frequency of marijuana use (frequent, moderate and infrequent; N = 27, 18, and 30, respectively) and non-using controls (N = 74). Chronic marijuana use showed no significant effect on hormone concentrations in either men or women.

Prolonged apparent half-life of delta 1-tetrahydrocannabinol in plasma of chronic marijuana users

The aim of this study was to characterize the elimination half-life of delta 1-tetrahydrocannabinol in blood plasma in chronic marijuana users. The subjects smoked four cigarettes during a two day period, each cigarette containing 15 mg deuterium-labelled delta 1-tetrahydrocannabinol. The plasma concentrations of deuterium-labelled tetrahydrocannabinol were measured for 13 days using gas chromatography-mass spectrometry equipped with selected ion monitoring. The elimination half-life for delta 1-tetrahydrocannabinol in blood plasma was calculated to be 4.1 +/- 1.1 days (range 2.9-5.0 days) from the two week plasma level curves. Albeit the present results are based upon a small sample, an elimination half-life of delta 1-tetrahydrocannabinol in blood plasma of about 4 days is more in line with apparent half-life excretion of delta 1-tetrahydrocannabinol metabolites in the urine of chronic marijuana smokers.

[Circadian neuroendocrinologic profile in patients with multiple drug abuse]

13 cases of politoxicomania that had undergone stationary treatment and, at the time of observation, were in rehabilitation, comprised the case load of this study. They were compared with 10 test persons in good state of health. In order to obtain circadine hormone profiles for melatonine, cortisol, human growth hormones (HGH) and thyroid stimulating hormones (TSH), blood samples were taken every hour from 6 pm until 7 am the following morning. The test cycle commenced with obtainment of a biochemical blood profile and a drug-oriented urine analysis. The cases were assorted into three therapy groups: Group 1: complete abstinence. Group 2: no hard drug intake. Group 3: acute relapse after a prolonged period of abstinence. This categorization (i.e. abstinence, soft or hard drug intake) was clearly mirrored by significant differences in the hormone profiles: the group of "abstinents" showed remarkably higher melatonine and cortisole levels than the acute relapsive cases. HGH and TSH profiles showed partly pathological levels which appeared unrelated, however, to the incidence of abstinence, or the manner of drug intake. Compared to the healthy control group, the test cases showed an increase of liver enzymes (Gamma-GT, SGOT, SGPT and LDH) but there was no marked difference between the 3 user categories themselves. The pathological neuroendocrine findings identified in test patients after a long period of abstinence are indicative of changes possibly based on genetic disposition rather than on abusive habits. The issue of self-inflicted damage, therefore, becomes a questionable one.

Acute effects of natural and synthetic cannabis compounds on prolactin levels in human males

Plasma prolactin levels were determined in 23 adult males prior to and following administration of delta 9-tetrahydrocannabinol (THC) (17.5 mg orally), a synthetic cannabis compound, Nabilone (2 mg orally), a 1-g marihuana cigarette containing 1.83% THC, smoked under controlled conditions and placebo capsules and cigarettes for each of the active cannabis compounds. In order to control for possible influence of previous cannabis use history on prolactin response, three groups of subjects were studied--regular (daily) marihuana users, intermittent (weekly) marihuana users, and occasional (monthly) marihuana users. Each subject served as his own control for each drug condition. Double blind studies were conducted on a residential research ward. All baseline prolactin values were within the normal range for healthy adult males. There were no statistically significant differences in plasma prolactin levels among the three subject groups prior to administration of THC, Nabilone, marihuana or their respective placebos. There were no statistically significant changes in prolactin levels following TCH, Nabilone or marihuana smoking. Only placebo administration to regular and occasional marihuana users was followed by a significant increase in plasma prolactin levels. These findings indicate that acute administration of cannabis compounds, either orally or via smoking, does not significantly affect plasma prolactin levels in adult human males.

Effects of acute cannabis use and short-term deprivation on plasma prolactin and dopamine-beta-hydroxylase in long-term users

Six long-term cannabis users (10 - 44 years of use) were studied for four days during which cannabis smoking was followed by three days deprivation and smoking on the fourth day. Blood samples were taken at - 30, + 30 and + 120 minutes from each smoking and once in every deprivation day. Pulse rate and blood pressure were measured before each blood sample. Prolactin and dopamine-beta-hydroxylase activity were estimated in plasma. On the third deprivation day, both prolactin and dopamine-beta-hydroxylase were significantly elevated compared to the pre-smoking values, but returned to them after the second cannabis use. The mean arterial pressure followed the same course. The data suggest that cannabis use in man reduces noradrenergic and enhances dopaminergic activity, while deprivation has the opposite effect, possibly through presynaptic receptor mechanisms.

Thiocyanate and drinking during pregnancy

Alcohol appears to have a relatively direct effect in decreasing fetal growth; however, it also appears that other factors associated with alcohol consumption may also contribute to lowered birthweight. Three studies have suggested that beverage source of alcohol may be a determinant of decreased intrauterine growth and that beer may have a comparatively greater effect than wine and liquor. Since beer is reported to contain thiocyanate (SCN), a substance which has been implicated as a determinant of fetal growth retardation in relation to cigarette smoking, we studied maternal and fetal serum SCN levels in 82 pregnancies. After controlling for maternal characteristics, gestational age, and tobacco and marijuana use, the quantity of beer consumed was found to have a significant positive correlation with fetal serum SCN (p less than 0.005). Consumption of other types of alcoholic beverages was not significantly associated with elevated fetal serum SCN, although the numbers of wine and liquor drinkers in this study were limited. Further research is warranted to explore the possibility that the correlation of beer consumption with increased SCN might provide at least one explanation for the reported linkage of diminished fetal growth and beer drinking.

Measurement of delta 1-tetrahydrocannabinol in plasma to the low picogram range by gas chromatography-mass spectrometry using metastable ion detection

A method for the assay of delta 1-tetrahydrocannabinol (delta 1-THC) in plasma using combined gas chromatography-mass spectrometry with metastable ion monitoring is described. delta 1-THC was extracted with hexane and the extracts were methylated with diazomethane to shift the peaks produced by endogenous plasma constituents away from the cannabinoid region. The delta 1-THC was then converted into its trimethylsilyl derivative and quantitated using the metastable ion at m/z 371 formed in the M+ leads to [M - CH3]+ transition with [1",1",2",2"-2H4]cannabinol as the internal standard. delta 1-THC could be measured to 5 pg/ml in plasma. This assay is 20-100 times more sensitive than existing assays and has the advantage of not needing the usual extensive purification step.

Levels of erythrocyte 2,3 DPG and ATP in heavy hashish smokers

The variations in concentration of ATP and 2,3 DPG, and in lactic acid production as a function of time, were measured in the erythrocytes of heavy smokers. Results indicate that the most remarkable reduction in concentration of the compounds examined occurred at 30 and 45 min after hashish smoking. The findings are discussed in connection with the possible influence of hashish components, especially delta 9-THC, on the erythrocyte glycolytic pathway.