THCCOOH concentrations in whole blood: Are they useful in discriminating occasional from heavy smokers?

Some forensic and clinical circumstances require knowledge of the frequency of drug use. Care of the patient, administrative, and legal consequences will be different if the subject is a regular or an occasional cannabis smoker. To this end, 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) has been proposed as a criterion to help to distinguish between these two groups of users. However, to date this indicator has not been adequately assessed under experimental conditions. We carried out a controlled administration study of smoked cannabis with a placebo. Cannabinoid levels were determined in whole blood using tandem mass spectrometry. Significantly high differences in THCCOOH concentrations were found between the two groups when measured during the screening visit, prior to the smoking session, and throughout the day of the experiment. Receiver operating characteristic (ROC) curves were determined and two threshold criteria were proposed in order to distinguish between these groups: a free THCCOOH concentration below 3 µg/L suggested an occasional consumption (≤ 1 joint/week) while a concentration higher than 40 µg/L corresponded to a heavy use (≥ 10 joints/month). These thresholds were tested and found to be consistent with previously published experimental data. The decision threshold of 40 µg/L could be a cut-off for possible disqualification for driving while under the influence of cannabis. A further medical assessment and follow-up would be necessary for the reissuing of a driving license once abstinence from cannabis has been demonstrated. A THCCOOH level below 3 µg/L would indicate that no medical assessment is required. Copyright © 2013 John Wiley & Sons, Ltd.

Do Swiss adolescents perceive the negative effects of their illegal substance use?

This study explores adolescents' perceptions of adverse consequences linked to their illegal psychoactive substance (IPS) use, as they are often thought to minimise them. From a Swiss nationally representative sample of 8740 adolescents aged 16 to 20 pursuing post-mandatory education, 2515 participants reported IPS use in the past month on a self-administered anonymous questionnaire. The percentages of participants reporting problems in four areas (individual, school, relationships and sexual) were assessed, depending on the type of IPS consumption over the last 30 days: occasional cannabis users: ≤2 times; regular cannabis users: ≥3 times; and poly-consumers: cannabis plus at least one other substance used. The percentages varied significantly across these three groups with 26.9% of occasional users, 53.8% of regular users, and 73.3% of poly-consumers reporting at least one problem. Compared to occasional cannabis users, poly-consumers were more likely to report problems in all four categories [relative risk ratio (RRR): 3.38 to 5.44], while regular cannabis users often reported only school and relationship problems [RRR: 2.43 to 3.23]. Thus, many adolescents seem to perceive the negative effects of their IPS use, with heavier consumption being associated with increasing problems. Physicians should feel confident questioning adolescents on the adverse consequences of their IPS consumption, as they are likely to be responsive on this issue.

Inferring about individual drug and schizotypy effects on cognitive functioning in polydrug using mephedrone users before and after clubbing

Objective: Mephedrone has been recently made illegal in Europe, but little empirical evidence is available on its impact on human cognitive functions. We investigated acute and chronic effects of mephedrone consumption on drug-sensitive cognitive measures, while also accounting for the influence of associated additional drug use and personality features. Method: Twenty-six volunteers from the general population performed tasks measuring verbal learning, verbal fluency and cognitive flexibility before and after a potential drug-taking situation (pre- and post-clubbing at dance clubs, respectively). Participants also provided information on chronic and recent drug use, schizotypal (O-LIFE) and depressive symptoms (Beck depression inventory), sleep pattern and premorbid IQ. Results: We found that i) mephedrone users performed worse than non-users pre-clubbing, and deteriorated from the pre-clubbing to the post-clubbing assessment, ii) pre-clubbing cannabis and amphetamine (not mephedrone) use predicted relative cognitive attenuations, iii) post-clubbing, depression scores predicted relative cognitive attenuations, and iv) schizotypy was largely unrelated to cognitive functioning, apart from a negative relationship between cognitive disorganisation and verbal fluency. Conclusion: Results suggest that polydrug use and depressive symptoms in the general population negatively affect cognition. For schizotypy, only elevated cognitive disorganisation showed potential links to a pathological cognitive profile previously reported along the psychosis dimension.

Duration of untreated psychosis: a proposition regarding treatment definition.

Aim: Duration of untreated psychosis (DUP) refers to the time elapsing between psychosis onset and treatment initiation. Despite a certain degree of consensus regarding the definition of psychosis onset, the definition of treatment commencement varies greatly between studies and DUP may be underestimated due to lack of agreement. In the present study, three sets of criteria to define the end of the untreated period were applied in a first-episode psychosis cohort to assess the impact of the choice of definition on DUP estimation. Methods: The DUP of 117 patients admitted in the Treatment and Early Intervention in Psychosis Program Psychosis in Lausanne was measured using the following sets of criteria to define treatment onset: (i) initiation of antipsychotic medication; (ii) entry into a specialized programme; and (iii) entry into a specialized programme and adequate medication with a good compliance. Results: DUP varied greatly according to definitions, the most restrictive criteria leading to the longest DUP (median DUP1 = 2.2 months, DUP2 = 7.4 months and DUP3 = 13.6 months). A percentage of 19.7 of the patients who did not meet these restrictive criteria had poorer premorbid functioning and were more likely to use cannabis. Longer DUP3 was associated with poorer premorbid functioning and with younger age at onset of psychosis. Conclusion: These results underline the need for a unique and standardized definition of the end of DUP. We suggest that the most restrictive definition of treatment should be used when using the DUP concept in future research.

Non-medical prescription drug and illicit street drug use among young Swiss men and associated mental health issues.

Non-medical use of prescription drugs (NMUPD) is increasing among the general population, particularly among teenagers and young adults. Although prescription drugs are considered safer than illicit street drugs, NMUPD can lead to detrimental consequences. The aim of the present study was to investigate the relationship between drug use (NMUPD on the one side, illicit street drugs on the other side) with mental health issues and then compare these associations. A representative sample of 5719 young Swiss men aged around 20 years filled in a questionnaire as part of the ongoing baseline Cohort Study on Substance Use Risk Factors (C-SURF). Drug use (16 illicit street drugs and 5 NMUPDs, including sleeping pills, sedatives, pain killers, antidepressants, stimulants) and mental health issues (depression, SF12) were assessed. Simple and multiple linear regressions were employed. In simple regressions, all illicit and prescription drugs were associated with poorer mental health. In multiple regressions, most of the NMUPDs, except for stimulants, were significantly associated with poorer mental health and with depression. On the contrary, the only associations that remained significant between illicit street drugs and mental health involved cannabis. NMUPD is of growing concern not only because of its increasing occurrence, but also because of its association with depression and mental health problems, which is stronger than the association observed between these problems and illicit street drug use, excepted for cannabis. Therefore, NMUPD must be considered in screening for substance use prevention purposes.

On the cellular site of two-pore channel TPC1 action in the Poaceae.

The slow vacuolar (SV) channel has been characterized in different dicots by patch-clamp recordings. This channel represents the major cation conductance of the largest organelle in most plant cells. Studies with the tpc1-2 mutant of the model dicot plant Arabidopsis thaliana identified the SV channel as the product of the TPC1 gene. By contrast, research on rice and wheat TPC1 suggested that the monocot gene encodes a plasma membrane calcium-permeable channel. To explore the site of action of grass TPC1 channels, we expressed OsTPC1 from rice (Oryza sativa) and TaTPC1 from wheat (Triticum aestivum) in the background of the Arabidopsis tpc1-2 mutant. Cross-species tpc1 complementation and patch-clamping of vacuoles using Arabidopsis and rice tpc1 null mutants documented that both monocot TPC1 genes were capable of rescuing the SV channel deficit. Vacuoles from wild-type rice but not the tpc1 loss-of-function mutant harbor SV channels exhibiting the hallmark properties of dicot TPC1/SV channels. When expressed in human embryonic kidney (HEK293) cells OsTPC1 was targeted to Lysotracker-Red-positive organelles. The finding that the rice TPC1, just like those from the model plant Arabidopsis and even animal cells, is localized and active in lyso-vacuolar membranes associates this cation channel species with endomembrane function.

Beverage preferences and associated drinking patterns, consequences and other substance use behaviours.

BACKGROUND: Studies about beverage preferences in a country in which wine drinking is relatively widespread (like Switzerland) are scarce. Therefore, the main aims of the present study were to examine the associations between beverage preferences and drinking patterns, alcohol-related consequences and the use of other substances among Swiss young men. METHODS: The analytical sample consisted of 5399 Swiss men who participated in the Cohort Study on Substance Use Risk Factors (C-SURF) and had been drinking alcohol over the preceding 12 months. Logistic regression analyses were conducted to study the associations between preference for a particular beverage and (i) drinking patterns, (ii) negative alcohol-related consequences and (iii) the (at-risk) use of cigarettes, cannabis and other illicit drugs. RESULTS: Preference for beer was associated with risky drinking patterns and, comparable with a preference for strong alcohol, with the use of illicit substances (cannabis and other illicit drugs). In contrast, a preference for wine was associated with low-risk alcohol consumption and a reduced likelihood of experiencing at least four negative alcohol-related consequences or of daily cigarette smoking. Furthermore, the likelihood of negative outcomes (alcohol-related consequences; use of other substances) increased among people with risky drinking behaviours, independent of beverage preference. CONCLUSIONS: In our survey, beer preference was associated with risky drinking patterns and illicit drug use. Alcohol polices to prevent large quantities of alcohol consumption, especially of cheaper spirits like beer, should be considered to reduce total alcohol consumption and the negative consequences associated with these beverage types.

Drugs, schizotypy and cognition: Cognitive attenuations seem more consistently associated with substance use than schizotypal symptoms

Psychosis is a debilitating disease, causing harm to the individual and society. Since early detection of the disease is associated with a more benign course, factors are warranted that enable the early detection of psychosis. In the present thesis we will be focusing on two potential risk factors, namely schizotypy and drug use. The schizotypy concept, originally developed by Meehl (1962), states that schizophrenia symptoms exist on a spectrum, with symptoms ranging from the most severe in patients with schizophrenia to the least affected individual in the general population. Along the schizophrenia spectrum cognitive impairments are commonly found, for instance reduced hemispheric asymmetry or frontal lobe functions. The second risk factor (drug use), affects similar cognitive functions as those attenuated along the schizophrenia spectrum, and drug use is elevated in schizophrenia and people scoring high on schizotypy. Therefore, we set out to investigate whether cognitive attenuations formerly allocated to schizotypal symptoms could have been influenced by elevated substance use in this population. To test this idea, we assessed various drugs (nicotine, cannabis, mephedrone, general substance dependence) and schizotypy symptoms (O-LIFE), and measured either hemispheric asymmetry of function (left hemisphere dominance for language, and right hemisphere dominance for facial processing) or functions largely relying on the frontal lobes (such as cognitive flexibility, working memory, verbal short-term memory, verbal learning and verbal fluency). Results of all studies suggest that it is mostly drugs, and not schizotypy in general that predict cognitive functioning. Therefore, cognitive attenuations subscribed to schizotypy dimensions are likely to have been affected by enhanced drug use. Future studies should extend the list of potential risk factors (e.g. depression and IQ) to acquire a comprehensive overview of the most reliable predictors of disadvantageous cognitive profiles.

Sexual dysfunctions among young men: prevalence and associated factors.

PURPOSE: The purposes of this study are to measure the prevalence of premature ejaculation (PE) and erectile dysfunction (ED) among a population of Swiss young men and to assess which factors are associated with these sexual dysfunctions in this age-group. METHODS: For each condition (PE and ED), we performed separate analyses comparing young men suffering from the condition with those who were not. Groups were compared for substance use (tobacco, alcohol, cannabis, other illegal drugs, and medication without a prescription), self-reported body mass index, sexual orientation, physical activity, professional activity, sexual experience (sexual life length and age at first intercourse), depression status, mental health, and physical health in a bivariate analysis. We then used a log-linear analysis to consider all significant variables simultaneously. RESULTS: Prevalence rates for PE and ED were 11% and 30%, respectively. Poor mental health was the only variable to have a direct association with both conditions after controlling for potential confounders. In addition, PE was directly associated with tobacco, illegal drugs, professional activity, and physical activity, whereas ED was directly linked with medication without a prescription, length of sexual life, and physical health. CONCLUSIONS: In Switzerland, one-third of young men suffer from at least one sexual dysfunction. Multiple health-compromising factors are associated with these dysfunctions. These should act as red flags for health professionals to encourage them to take any opportunity to talk about sexuality with their young male patients.

Body mass index and health-related quality of life among young Swiss men.

BACKGROUND: Studies about the association between body mass index (BMI) and health-related quality of life (HRQOL) are often limited, because they 1) did not include a broad range of health-risk behaviors as covariates; 2) relied on clinical samples, which might lead to biased results; and 3) did not incorporate underweight individuals. Hence, this study aims to examine associations between BMI (from being underweight through obesity) and HRQOL in a population-based sample, while considering multiple health-risk behaviors (low physical activity, risky alcohol consumption, daily cigarette smoking, frequent cannabis use) as well as socio-demographic characteristics. METHODS: A total of 5 387 young Swiss men (mean age = 19.99; standard deviation = 1.24) of a cross-sectional population-based study were included. BMI was calculated (kg/m²) based on self-reported height and weight and divided into 'underweight' (<18.5), 'normal weight' (18.5-24.9), 'overweight' (25.0-29.9) and 'obese' (≥30.0). Mental and physical HRQOL was assessed via the SF-12v2. Self-reported information on physical activity, substance use (alcohol, cigarettes, and cannabis) and socio-demographic characteristics also was collected. Logistic regression analyses were conducted to study the associations between BMI categories and below average mental or physical HRQOL. Substance use variables and socio-demographic variables were used as covariates. RESULTS: Altogether, 76.3% were normal weight, whereas 3.3% were underweight, 16.5% overweight and 3.9% obese. Being overweight or obese was associated with reduced physical HRQOL (adjusted OR [95% CI] = 1.58 [1.18-2.13] and 2.45 [1.57-3.83], respectively), whereas being underweight predicted reduced mental HRQOL (adjusted OR [95% CI] = 1.49 [1.08-2.05]). Surprisingly, obesity decreased the likelihood of experiencing below average mental HRQOL (adjusted OR [95% CI] = 0.66 [0.46-0.94]). Besides BMI, expressed as a categorical variable, all health-risk behaviors and socio-demographic variables were associated with reduced physical and/or mental HRQOL. CONCLUSIONS: Deviations from normal weight are, even after controlling for important health-risk behaviors and socio-demographic characteristics, associated with compromised physical or mental HRQOL among young men. Hence, preventive programs should aim to preserve or re-establish normal weight. The self-appraised positive mental well-being of obese men noted here, which possibly reflects a response shift, might complicate such efforts.

Dépendances [Addiction]

This year review emphasizes three aspects coming from addiction psychiatry: 1. Psychosis and cannabis: a motivational approach. 2. Connection between addiction services and psychiatric wards. 3. Use of antiepileptic agents in addiction medicine.

Identification and characterization of the members of the pho1 gene family in moss and rice

Inorganic phosphate (Pi) is one of the main nutrients limiting plant growth anddevelopment in many agro-ecosystems. In plants, phosphate is acquired from the soil by theroots, and is then transferred to the shoot via the xylem. In the model plant Arabidopsisthaliana, PHO1 was previously identified as being involved in loading Pi into the xylem ofroots. AtPHO1, belongs to a multigenic family composed of 10 additional members, namelyAtPHO1;H1 to AtPHO1;10. In this study, we aimed at further investigating the role of thePHO1 gene family in Pi homeostasis in plants, and to this end we isolated and characterizedthe PHO1 members of two main model plants, the moss Physcomitrella patens and the riceOryza sativa.In the bryophyte P. patens, bioinformatic analyses revealed the presence of seven AtPHO1homologues, highly similar to AtPHO1. The seven moss PHO1 genes, namely PpPHO1;1 toPpPHO1;7 appeared to be differentially regulated, both at the tissue level and in response toPi status. However only PpPHO1;1 and PpPHO1;7 were specifically up-regulated upon Pistarvation, suggesting a potential role in Pi homeostasis. We also characterized the responseof P. patens to Pi starvation, showing that higher and lower plants share some commonstrategies to adapt to Pi-deficiency.In the second part, focusing on the monocotyledon rice, we showed the existence of threePHO1 homologues OsPHO1;1 to OsPHO1;3, with the unique particularity of each havingNatural Antisense Transcripts (NATs). Molecular analyses revealed that both the sense andthe antisense OsPHO1;2 transcripts were by far the most abundantly expressed transcripts ofthe family, preferentially expressed in the roots. The stable expression of OsPHO1;2 in allconditions tested, in opposition with the highly induced antisense transcript upon Pistarvation, suggest a putative role for the antisense in regulating the sense transcript.Moreover, mutant analyses revealed that OsPHO1;2 plays a key role in Pi homeostasis, intransferring Pi from the root to the shoot. Finally, complementing the pho1 mutant inArabidopsis, characterized by low Pi in the shoot and reduced growth, with the riceOsPHO1;2 gene revealed a new role for PHO1 in Pi signaling. Indeed, the complementedplants showed normal growth, with however low Pi content.

Health risk behaviors in adolescents with chronic conditions

OBJECTIVE: The objective of this study was to compare the frequency of risk behaviors and to measure the extent of co-occurrence of these behaviors in chronically ill and healthy adolescents. METHODS: Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health database, a nationally representative survey of 7548 adolescents in postmandatory school aged 16 to 20 years. There were 760 subjects who reported a chronic illness and/or a disability. The comparison group consisted of 6493 subjects who answered negatively to both questions. We defined 8 risk behaviors: daily smoking, alcohol misuse, current cannabis use, current use of any other illegal drug, early sexual debut, eating disorder, violent acts, and antisocial acts. We analyzed each behavior and the sum of behaviors, controlling for age, gender, academic track, parents' education level, depression, and health status. Results are given as adjusted odds ratios using the comparison group as the reference category. RESULTS: Youth with a chronic condition were more likely to smoke daily, to be current cannabis users, and to have performed violent or antisocial acts. Youth with a chronic condition were also more likely to report 3 or >or=4 risk behaviors. CONCLUSIONS: These results indicate that having a chronic condition carries additional risks for engaging in health risk behaviors and emphasize the importance of health risk screening and preventive counseling for young people in general and among those suffering from chronic conditions in particular.