Marco Colizzi

Effects of continuation, frequency, and type of cannabis use on relapse in the first 2 years after onset of psychosis: an observational study

BACKGROUND Although cannabis use after a first episode of psychosis has been associated with relapse, little is known about the determinants of this most preventable risk factor for relapse of psychosis. Here we aimed to study whether the effects on outcome vary depending on the type of cannabis consumed and usage pattern. METHODS In this observational study, we prospectively recruited and followed up patients aged 18-65 years who presented with their first episode of psychosis to psychiatric services in south London, London, UK. Relapse of psychosis within 2 years after onset of psychosis was defined as risk of subsequent admission to hospital. We classified patients into different patterns of cannabis use based on continuity of use after onset of psychosis, potency of cannabis consumed, and frequency of use after the onset of their illness. We used multiple regression analyses (logistic or binominal) to compare the different cannabis use groups and propensity score analysis to validate the results. FINDINGS Between April 12, 2002, and July 26, 2013, 256 patients presented with a first episode of psychosis. We did follow-up assessments for these patients until September, 2015. Simple analyses showed that former regular users of cannabis who stopped after the onset of psychosis had the most favourable illness course with regards to relapse. In multiple analysis, continued high-frequency users (ie, daily use in all 24 months) of high-potency (skunk-like) cannabis had the worst outcome, indexed as an increased risk for a subsequent relapse (odds ratio [OR] 3·28; 95% CI 1·22-9·18), more relapses (incidence rate ratio 1·77; 95% CI 0·96-3·25), fewer months until a relapse occurred (b -0·22; 95% CI -0·40 to -0·04), and more intense psychiatric care (OR 3·16; 95% CI 1·26-8·09) after the onset of psychosis. INTERPRETATION Adverse effects associated with continued use of cannabis after the onset of a first episode of psychosis depend on the specific patterns of use. Possible interventions could focus on persuading cannabis-using patients with psychosis to reduce use or shift to less potent forms of cannabis. FUNDING National Institute for Health Research (NIHR).

Hormonal Treatment Reduces Psychobiological Distress in Gender Identity Disorder, Independently of the Attachment Style

INTRODUCTION Gender identity disorder may be a stressful situation. Hormonal treatment seemed to improve the general health as it reduces psychological and social distress. The attachment style seemed to regulate distress in insecure individuals as they are more exposed to hypothalamic-pituitary-adrenal system dysregulation and subjective stress. AIM The objectives of the study were to evaluate the presence of psychobiological distress and insecure attachment in transsexuals and to study their stress levels with reference to the hormonal treatment and the attachment pattern. METHODS We investigated 70 transsexual patients. We measured the cortisol levels and the perceived stress before starting the hormonal therapy and after about 12 months. We studied the representation of attachment in transsexuals by a backward investigation in the relations between them and their caregivers. MAIN OUTCOME MEASURES We used blood samples for assessing cortisol awakening response (CAR); we used the Perceived Stress Scale for evaluating self-reported perceived stress and the Adult Attachment Interview to determine attachment styles. RESULTS At enrollment, transsexuals reported elevated CAR; their values were out of normal. They expressed higher perceived stress and more attachment insecurity, with respect to normative sample data. When treated with hormone therapy, transsexuals reported significantly lower CAR (P < 0.001), falling within the normal range for cortisol levels. Treated transsexuals showed also lower perceived stress (P < 0.001), with levels similar to normative samples. The insecure attachment styles were associated with higher CAR and perceived stress in untreated transsexuals (P < 0.01). Treated transsexuals did not expressed significant differences in CAR and perceived stress by attachment. CONCLUSION Our results suggested that untreated patients suffer from a higher degree of stress and that attachment insecurity negatively impacts the stress management. Initiating the hormonal treatment seemed to have a positive effect in reducing stress levels, whatever the attachment style may be.

Effect of cannabis on glutamate signalling in the brain: A systematic review of human and animal evidence.

Use of cannabis or delta-9-tetrahydrocannabinol (Δ9-THC), its main psychoactive ingredient, is associated with psychotic symptoms or disorder. However, the neurochemical mechanism that may underlie this psychotomimetic effect is poorly understood. Although dopaminergic dysfunction is generally recognized as the final common pathway in psychosis, evidence of the effects of Δ9-THC or cannabis use on dopaminergic measures in the brain is equivocal. In fact, it is thought that cannabis or Δ9-THC may not act on dopamine firing directly but indirectly by altering glutamate neurotransmission. Here we systematically review all studies examining acute and chronic effects of cannabis or Δ9-THC on glutamate signalling in both animals and man. Limited research carried out in humans tends to support the evidence that chronic cannabis use reduces levels of glutamate-derived metabolites in both cortical and subcortical brain areas. Research in animals tends to consistently suggest that Δ9-THC depresses glutamate synaptic transmission via CB1 receptor activation, affecting glutamate release, inhibiting receptors and transporters function, reducing enzyme activity, and disrupting glutamate synaptic plasticity after prolonged exposure.

Functional genetic variation of the cannabinoid receptor 1 and cannabis use interact on prefrontal connectivity and related working memory behavior

Cannabinoid signaling is involved in different brain functions and it is mediated by the cannabinoid receptor 1 (CNR1), which is encoded by the CNR1 gene. Previous evidence suggests an association between cognition and cannabis use. The logical interaction between genetically determined cannabinoid signaling and cannabis use has not been determined. Therefore, we investigated whether CNR1 variation predicts CNR1 prefrontal mRNA expression in postmortem prefrontal human tissue. Then, we studied whether functional variation in CNR1 and cannabis exposure interact in modulating prefrontal function and related behavior during working memory processing. Thus, 208 healthy subjects (113 males) were genotyped for the relevant functional SNP and were evaluated for cannabis use by the Cannabis Experience Questionnaire. All individuals performed the 2-back working memory task during functional magnetic resonance imaging. CNR1 rs1406977 was associated with prefrontal mRNA and individuals carrying a G allele had reduced CNR1 prefrontal mRNA levels compared with AA subjects. Moreover, functional connectivity MRI demonstrated that G carriers who were also cannabis users had greater functional connectivity in the left ventrolateral prefrontal cortex and reduced working memory behavioral accuracy during the 2-back task compared with the other groups. Overall, our results indicate that the deleterious effects of cannabis use are more evident on a specific genetic background related to its receptor expression.

Dissociative symptoms in individuals with gender dysphoria: is the elevated prevalence real?

This study evaluated dissociative symptomatology, childhood trauma and body uneasiness in 118 individuals with gender dysphoria, also evaluating dissociative symptoms in follow-up assessments after sex reassignment procedures were performed. We used both clinical interviews (Dissociative Disorders Interview Schedule) and self-reported scales (Dissociative Experiences Scale). A dissociative disorder of any kind seemed to be greatly prevalent (29.6%). Moreover, individuals with gender dysphoria had a high prevalence of lifetime major depressive episode (45.8%), suicide attempts (21.2%) and childhood trauma (45.8%), and all these conditions were more frequent in patients who fulfilled diagnostic criteria for any kind of dissociative disorder. Finally, when treated, patients reported lower dissociative symptoms. Results confirmed previous research about distress in gender dysphoria and improved mental health due to sex reassignment procedures. However, it resulted to be difficult to ascertain dissociation in the context of gender dysphoria, because of the similarities between the two conditions and the possible limited application of clinical instruments which do not provide an adequate differential diagnosis. Therefore, because the body uneasiness is common to dissociative experiences and gender dysphoria, the question is whether dissociation is to be seen not as an expression of pathological dissociative experiences but as a genuine feature of gender dysphoria.

Substance use, medication adherence and outcome one year following a first episode of psychosis

Both substance use and poor medication adherence are associated with poor outcome in psychosis. To clarify the contributions of substance use and poor medication adherence to poor outcome in the year following a first episode of psychosis, 205 patients were evaluated for use of tobacco, alcohol, cannabis and stimulants at their psychosis onset, and in a 1-year follow-up. Data on medication adherence and symptom remission were also collected. Patients had high rates of overall substance use before (37-65%) and after psychosis onset (45-66%). 44% showed poor medication adherence and 55% did not reach remission from psychosis. Nicotine dependence and cannabis use after psychosis onset significantly predicted both poor medication adherence and non-remission, and poor medication adherence mediated the effects of these substances on non-remission. In conclusion, medication adherence lies on the causal pathway between nicotine dependence and cannabis on the one hand and non-remission on the other.

The effect of cross-sex hormonal treatment on gender dysphoria individuals' mental health: a systematic review

Cross-sex hormonal treatment represents a main aspect of gender dysphoria health care pathway. However, it is still debated whether this intervention translates into a better mental well-being for the individual and which mechanisms may underlie this association. Although sex reassignment surgery has been the subject of extensive investigation, few studies have specifically focused on hormonal treatment in recent years. Here, we systematically review all studies examining the effect of cross-sex hormonal treatment on mental health and well-being in gender dysphoria. Research tends to support the evidence that hormone therapy reduces symptoms of anxiety and dissociation, lowering perceived and social distress and improving quality of life and self-esteem in both male-to-female and female-to-male individuals. Instead, compared to female-to-male individuals, hormone-treated male-to-female individuals seem to benefit more in terms of a reduction in their body uneasiness and personality-related psychopathology and an amelioration of their emotional functioning. Less consistent findings support an association between hormonal treatment and other mental health-related dimensions. In particular, depression, global psychopathology, and psychosocial functioning difficulties appear to reduce only in some studies, while others do not suggest any improvement in these domains. Results from longitudinal studies support more consistently the association between hormonal treatment and improved mental health. On the contrary, a number of cross-sectional studies do not support this evidence. This review provides possible biological explanation vs psychological explanation (direct effect vs indirect effect) for the hormonal treatment-induced better mental well-being. In conclusion, this review indicates that gender dysphoria-related mental distress may benefit from hormonal treatment intervention, suggesting a transient reaction to the nonsatisfaction connected to the incongruent body image rather than a stable psychiatric comorbidity. In this perspective, timely hormonal treatment intervention represents a crucial issue in gender dysphoria individuals’ mental health-related outcome.

Interaction between DRD2 and AKT1 genetic variations on risk of psychosis in cannabis users: a case–control study

Genetic factors may explain the differences in individual sensitivity to the psychosis-inducing effects of cannabis.1,2 In view of the converging data from candidate gene and genome-wide association studies that the D2-AKT1 signaling pathway is relevant for the pathophysiology and outcome of schizophrenia,3 and on the basis of previous association between cannabis-related psychosis and both DRD2 (rs1076560)1 and AKT1 (rs2494732),2 we hypothesized that these polymorphisms interact in increasing the risk of psychosis in cannabis users. We expected the genetic pathway × cannabis use interaction model to better predict the individual’s odds of psychotic disorder than the single candidate gene×cannabis use interaction model.

Concomitant psychiatric problems and hormonal treatment induced metabolic syndrome in gender dysphoria individuals: a 2 year follow-up study.

OBJECTIVE Several studies indicate increased prevalence of metabolic syndrome (MetS) among patients with psychiatric disorders as well as among individuals with gender dysphoria (GD) treated by cross-sex hormonal treatment. However, the MetS prevalence among hormone treated GD individuals suffering from psychiatric problems has not been detected. METHODS From a sample of 146 GD patients we selected 122 metabolically healthy individuals in order to investigate the prevalence of MetS after the beginning of the cross-sex hormonal treatment in a 2 year follow-up assessment. Furthermore, we assessed differences in MetS prevalence between hormone treated GD patients with and without concomitant psychiatric problems. RESULTS When treated with hormone therapy, GD patients reported changes in several parameters which are clustered in MetS, with statistically significant differences compared to baseline. Glyco-insulinemic alterations were more pronounced in male to female patients (MtFs). However, weight gain, waist circumference increases, blood pressure increases, and lipid alterations were similar in MtFs and female to male patients (FtMs). 14.8% of the sample at year 1 and 17.2% at year 2 developed MetS. Among patients with concomitant psychiatric problems, 50% at year 1 and 55% at year 2 developed MetS against 8% at year 1 and 10% at year 2 of patients without concomitant psychiatric problems. CONCLUSION This study indicates that sex hormones induce MetS in a relatively low proportion of healthy GD individuals and especially during the first year of hormonal treatment. Most importantly, concomitant psychiatric problems are associated with considerably greater MetS prevalence in hormone treated GD individuals.

Does Cannabis Composition Matter? Differential Effects of Delta-9-tetrahydrocannabinol and Cannabidiol on Human Cognition

Purpose of ReviewThe lack of clarity about the effect of cannabis use on cognition may be attributable to the considerable heterogeneity among studies in terms of cannabis composition. This article selectively reviews studies examining the distinctive effects of cannabinoids on human cognition, particularly those of delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD).Recent FindingsResearch indicates that ∆9-THC administration acutely impairs cognition, particularly memory and emotional processing. Limited evidence suggests that CBD administration might improve cognition in cannabis users but not in individuals with neuropsychiatric disorders. Moreover, studies indicate that some acute Δ9-THC-induced cognitive impairments may be prevented if Δ9-THC is administered in combination or following CBD treatment. Δ9-THC and CBD have also shown opposite effects on cognition-related brain activation, possibly reflecting their antagonistic behavioral effects.SummaryResearch suggests greater cognitive impairments in individuals when exposed to high ∆9-THC or low CBD cannabis. It is unclear whether at specific concentrations CBD might outweigh any harmful effects of Δ9-THC on cognition.