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American Journal of Men's Health 2019Globally, there is increasing usage and legalization of cannabis. In addition to its reported therapeutic effects, cannabis has several health risks which are not... (Meta-Analysis)
Meta-Analysis
Globally, there is increasing usage and legalization of cannabis. In addition to its reported therapeutic effects, cannabis has several health risks which are not clearly defined. Erectile dysfunction (ED) is the most common male sexual disorder and there are plausible mechanisms linking cannabis use to ED. No attempt has been made to collate the literature on this topic. The aim of this review was to summarize the prevalence and risk of ED in cannabis users compared to controls. A systematic review of major databases from inception to January 1, 2019, without language restriction, was undertaken to identify studies investigating cannabis use and presence of ED. The analysis compared the prevalence of ED in cannabis users versus controls. Consequently, the odds ratio (OR) with 95% confidence intervals (CI) was calculated, applying a random-effect model. Five case-control studies were included with data from 3,395 healthy men, 1,035 using cannabis (smoking) and 2,360 nonusers. The overall prevalence of ED in cannabis users was 69.1% (95% CI: 38.0-89.1), whilst the correspondent figure in controls was 34.7% (95% CI: 20.3-52.7). The OR of ED in cannabis users was almost four times that of controls (OR = 3.83; 95% CI: 1.30-11.28; = .02), even if characterized by high heterogeneity ( = 90%) and the prediction intervals overlapped 1.00 (95% CI: 0.35-7.26). Data suggest that ED is twice as high in cannabis users compared to controls. Future longitudinal research is needed to confirm/refute this and explore if a dose-response relationship between cannabis and ED may be evident.
Topics: Adult; Cannabis; Case-Control Studies; Erectile Dysfunction; Humans; Male; Marijuana Abuse; Middle Aged; Prevalence; Reference Values; Risk Assessment
PubMed: 31795801
DOI: 10.1177/1557988319892464 -
Psychological Medicine Oct 2020Risk prediction algorithms have long been used in health research and practice (e.g. prediction of cardiovascular disease and diabetes). However, similar tools have not... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Risk prediction algorithms have long been used in health research and practice (e.g. prediction of cardiovascular disease and diabetes). However, similar tools have not been developed for mental health. For example, for psychotic disorders, attempts to sum environmental risk are rare, unsystematic and dictated by available data. In light of this, we sought to develop a valid, easy to use measure of the aggregate environmental risk score (ERS) for psychotic disorders.
METHODS
We reviewed the literature to identify well-replicated and validated environmental risk factors for psychosis that combine a significant effect and large-enough prevalence. Pooled estimates of relative risks were taken from the largest available meta-analyses. We devised a method of scoring the level of exposure to each risk factor to estimate ERS. Relative risks were rounded as, due to the heterogeneity of the original studies, risk effects are imprecisely measured.
RESULTS
Six risk factors (ethnic minority status, urbanicity, high paternal age, obstetric complications, cannabis use and childhood adversity) were used to generate the ERS. A distribution for different levels of risk based on simulated data showed that most of the population would be at low/moderate risk with a small minority at increased environmental risk for psychosis.
CONCLUSIONS
This is the first systematic approach to develop an aggregate measure of environmental risk for psychoses in asymptomatic individuals. This can be used as a continuous measure of liability to disease; mostly relevant to areas where the original studies took place. Its predictive ability will improve with the collection of additional, population-specific data.
Topics: Adverse Childhood Experiences; Environment; Ethnicity; Female; Humans; Male; Marijuana Abuse; Minority Groups; Obstetric Labor Complications; Paternal Age; Pregnancy; Psychotic Disorders; Risk Assessment; Risk Factors; Urban Population
PubMed: 31535606
DOI: 10.1017/S0033291719002319 -
Cureus Sep 2023The prevalence of cannabis use disorders has become a noteworthy global public health issue. Understanding the neurobiological factors associated with cannabis use... (Review)
Review
The prevalence of cannabis use disorders has become a noteworthy global public health issue. Understanding the neurobiological factors associated with cannabis use disorder (CUD) is crucial for creating effective interventions. One such factor, the brain-derived neurotrophic factor (BDNF), has been linked to the onset and persistence of addictive behaviors. This systematic review aims to summarize the existing literature on BDNF levels in individuals with CUD to provide a comprehensive overview of the current evidence. A systematic search was conducted using electronic databases (PubMed, Scopus) for relevant studies. The search approach yielded a total of 785 articles, with 559 located in the PubMed database and 226 in Scopus. Studies reporting BDNF levels in individuals with CUD compared to healthy controls were included in this study. Ultimately, eight articles were included in this systematic review. The primary emphasis of these studies was on individuals who were cannabis users or had a dependency on cannabis. There is considerable variation in the estimated effect size among included studies due to heterogeneity; hence, a random effect model was used for meta-analysis. The findings of our study suggest that the effect size of BDNF levels was 0.25 with 95% CI (-0.55; 1.05) in cannabis users, which was not statistically significant (p-value=0.54). Therefore, it is important to interpret the results with caution, and additional research is warranted to investigate the potential factors contributing to this heterogeneity.
PubMed: 37900486
DOI: 10.7759/cureus.45960 -
International Journal of Molecular... Aug 2021marijuana, the common name for cannabis sativa preparations, is one of the most consumed drug all over the world, both at therapeutical and recreational levels. With the...
BACKGROUND
marijuana, the common name for cannabis sativa preparations, is one of the most consumed drug all over the world, both at therapeutical and recreational levels. With the legalization of medical uses of cannabis in many countries, and even its recreational use in most of these, the prevalence of marijuana use has markedly risen over the last decade. At the same time, there is also a higher prevalence in the health concerns related to cannabis use and abuse. Thus, it is mandatory for oral healthcare operators to know and deal with the consequences and effects of cannabis use on oral cavity health. This review will briefly summarize the components of cannabis and the endocannabinoid system, as well as the cellular and molecular mechanisms of biological cannabis action in human cells and biologic activities on tissues. We will also look into oropharyngeal tissue expression of cannabinoid receptors, together with a putative association of cannabis to several oral diseases. Therefore, this review will elaborate the basic biology and physiology of cannabinoids in human oral tissues with the aim of providing a better comprehension of the effects of its use and abuse on oral health, in order to include cannabinoid usage into dental patient health records as well as good medicinal practice.
METHODS
the paper selection was performed by PubMed/Medline and EMBASE electronic databases, and reported according to the PRISMA guidelines. The scientific products were included for qualitative analysis.
RESULTS
the paper search screened a total of 276 papers. After the initial screening and the eligibility assessment, a total of 32 articles were considered for the qualitative analysis.
CONCLUSIONS
today, cannabis consumption has been correlated to a higher risk of gingival and periodontal disease, oral infection and cancer of the oral cavity, while the physico-chemical activity has not been completely clarified. Further investigations are necessary to evaluate a therapeutic efficacy of this class of drugs for the promising treatment of several different diseases of the salivary glands and oral diseases.
Topics: Cannabinoids; Humans; Mouth Diseases; Oral Health; Substance-Related Disorders
PubMed: 34361095
DOI: 10.3390/ijms22158329 -
Accident; Analysis and Prevention Aug 2022Cannabis is the second most commonly used impairing substance by drivers, after alcohol. As more countries legalize cannabis, there is concern that cannabis-impaired... (Meta-Analysis)
Meta-Analysis
Cannabis is the second most commonly used impairing substance by drivers, after alcohol. As more countries legalize cannabis, there is concern that cannabis-impaired driving will increase. In many countries, police use roadside devices to test for oral fluid THC (the primary psychotropic component in cannabis) to identify drivers who used cannabis; including in countries with non-zero per se limits for THC in blood. This practice is questioned as previous research demonstrates a poor correlation between oral fluid and blood THC concentrations at the individual level. We conducted a meta-analysis to identify all research that compared oral fluid with blood THC levels. We obtained individual-level data from study authors and analyzed pooled individual-level data to calculate sensitivity and specificity of oral fluid THC (at various cut-off values) to detect blood THC above different concentration limits. Finally, we explored practical implications of using oral fluid THC in an enforcement context. Our review found THC concentrations measured in over 18,000 paired samples of oral fluid and blood. We found a good correlation between the presence of THC in oral fluid and presence of THC in blood (sensitivity = 71.2%, specificity = 97.7%). However oral fluid THC, at commonly used cut-off values, is less sensitive and less specific when used as a biomarker to detect people with blood THC concentrations above commonly used per se limits (such as 5 ng/mL). As such, there will be a large number of "false positive" tests if oral fluid THC testing were used as a biomarker for "illegal" THC concentrations in randomly selected drivers. We argue that the adverse implications of false positive oral fluid THC tests in this context outweigh the possible road safety benefits and we recommend against oral fluid THC screening in randomly selected drivers in countries with non-zero per se limits for blood THC. In contrast, oral fluid THC tests appear to be useful for investigating "high-risk" drivers who come to police attention because of evidence of impairment.
Topics: Accidents, Traffic; Biomarkers; Cannabis; Dronabinol; Humans; Policy; Saliva; Substance Abuse Detection
PubMed: 35640367
DOI: 10.1016/j.aap.2022.106694 -
Neuroscience and Biobehavioral Reviews Sep 2020Despite the high prevalence in patients with schizophrenia, the association of cannabis and nicotine use with negative symptoms remains unclear. We performed a... (Meta-Analysis)
Meta-Analysis
Despite the high prevalence in patients with schizophrenia, the association of cannabis and nicotine use with negative symptoms remains unclear. We performed a meta-analysis of observational studies addressing the association of cannabis and nicotine use with negative symptoms. Twenty cannabis studies (n = 2611) and 45 nicotine studies (n = 8942) were analyzed. There was no significant effect for current cannabis use alone or in combination with other substances. However, recently abstinent users of cannabis showed less severe negative symptoms than nonusers. Nicotine users were not different from nonusers with respect to negative symptoms. With respect to positive symptoms, very small increases were found for cannabis users and patients using nicotine along with other drugs. In conclusion, while patients with schizophrenia who use cannabis did not differ from nonusers, recently abstinent patients showed less severe negative symptoms than nonusers. This finding suggests that cannabis-using patients might be less susceptible to the development of negative symptoms. The amotivational effects of cannabis may obscure these differences in current users.
Topics: Cannabis; Hallucinogens; Humans; Marijuana Abuse; Nicotine; Observational Studies as Topic; Schizophrenia
PubMed: 32679232
DOI: 10.1016/j.neubiorev.2020.07.007 -
Psychopharmacology Oct 2021Regular cannabis use (i.e. ≥ monthly) is highly prevalent, with past year use being reported by ~ 200 million people globally.High reactivity to cannabis... (Review)
Review
RATIONALE
Regular cannabis use (i.e. ≥ monthly) is highly prevalent, with past year use being reported by ~ 200 million people globally.High reactivity to cannabis cues is a key feature of regular cannabis use and has been ascribed to greater cannabis exposure and craving, but the underlying neurobiology is yet to be systematically integrated.
OBJECTIVES
We aim to systematically summarise the findings from fMRI studies which examined brain function in cannabis users while exposed to cannabis vs neutral stimuli during a cue-reactivity fMRI task.
METHODS
A systematic search of PsycINFO, PubMed and Scopus databases was pre-registered in PROSPERO (CRD42020171750) and conducted following PRISMA guidelines. Eighteen studies met inclusion/exclusion criteria. Samples comprised 918 participants (340 female) aged 16-38 years. Of these, 603 were regular cannabis users, and 315 were controls.
RESULTS
The literature consistently reported greater brain activity in cannabis users while exposed to cannabis vs neutral stimuli in three key brain areas: the striatum, the prefrontal (anterior cingulate, middle frontal) and the parietal cortex (posterior cingulate/precuneus) and additional brain regions (hippocampus, amygdala, thalamus, occipital cortex). Preliminary correlations emerged between cannabis craving and the function of partially overlapping regions (amygdala, striatum, orbitofrontal cortex ).
CONCLUSIONS
Exposure to cannabis-cues may elicit greater brain function and thus trigger cravings in regular cannabis users and thus trigger cannabis craving. Standardised and longitudinal assessments of cannabis use and related problems are required to profile with greater precision the neurobiology of cannabis cue-reactivity, and its role in predicting cravings and relapse.
Topics: Brain; Cannabis; Cues; Humans; Magnetic Resonance Imaging; Marijuana Abuse
PubMed: 34505940
DOI: 10.1007/s00213-021-05973-x -
The American Journal of Drug and... Sep 2021While males are more likely diagnosed with cannabis use disorder (CUD), females are more susceptible to developing and maintaining CUD. Yet, for both sexes, CUD is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
While males are more likely diagnosed with cannabis use disorder (CUD), females are more susceptible to developing and maintaining CUD. Yet, for both sexes, CUD is associated with high rates of comorbid mental illness (MI).
OBJECTIVES
To identify and compare sex differences in the prevalence of comorbid CUD amongst individuals with/without MIs.
METHODS
This systematic review generated pooled odds ratios (OR) and 95% confidence intervals (CI) from 37 studies (including clinical trials, cohort, and case-control studies) among individuals with and without MIs, quantifying sex differences in rates of comorbid CUD. A meta-analysis was also completed.
RESULTS
In the CUD-only group, males were twice as likely to have CUD than females (OR = 2.0, CI = 1.9-2.1). Among MIs, males were more likely than females to have CUD comorbid with schizophrenia (OR ~2.6, CI = 2.5-2.7) and other psychotic, mood, and substance use disorders (1> OR <2.2, CI = 0.7-2.6). The reverse association (females > males) was observed for anxiety disorders and antisocial personality disorder (OR = 0.8, CI = 0.7-1.0). Among females, MIs increased the likelihood of having CUD, except for psychotic disorders and depression. A meta-analysis was inconclusive due to high heterogeneity across studies. Thus, comparisons across MI groups were not possible.
CONCLUSION
While males are more likely to be diagnosed with CUD, there are important sex differences in the prevalence of CUD across MI diagnoses that should be taken into account when approaching CUD prevention and determining treatment efficacy.
Topics: Comorbidity; Female; Humans; Male; Marijuana Abuse; Mental Disorders; Odds Ratio; Prevalence; Sex Distribution; Sex Factors
PubMed: 34280058
DOI: 10.1080/00952990.2021.1946071 -
Frontiers in Psychiatry 2022Abuses of most illegal drugs, including methamphetamine, marijuana, cocaine, heroin, and polydrug, are usually in conjunction with alcohol and tobacco. There are...
Abuses of most illegal drugs, including methamphetamine, marijuana, cocaine, heroin, and polydrug, are usually in conjunction with alcohol and tobacco. There are similarities and associations between the behavior, gene, and neurophysiology of such abusers, but the neural overlaps of their cue-reactivity and the correlation of neural overlap with drug craving still needs to be further explored. In this study, an Activation Likelihood Estimation (ALE) was performed on brain activation under legal (tobacco, alcohol) and illegal drug cues, for identifying the similarities in brain functions between different craving states. A Comprehensive meta-analysis (CMA) on the correlation coefficient between brain activation and craving scores in the selected literatures with subjective craving reports explained the degree of the craving via brain imaging results. In ALE, co-activation areas of the three cue-reactivity (posterior cingulate, caudate, and thalamus) suggest that the three cue-reactivity may all arouse drug-use identity which is a predictor of relapse and generation of conditioned reflexes under reward memory, thus leading to illegal drug relapses. In CMA, the brain activation was significantly correlated with subjective craving, with a correlation coefficient of 0.222. The neural overlap of tobacco, alcohol and most of the prevalent illegal drug cues not only further helps us understand the neural mechanism of substance co-abuse and relapse, but also provides implications to detoxification. Furthermore, the correlation between brain activation and craving is low, suggesting the accuracy of craving-based quantitative evaluation by neuroimaging remains unclear.
PubMed: 35463497
DOI: 10.3389/fpsyt.2022.779239 -
European Psychiatry : the Journal of... Jan 2020The implications of cannabis use in the onset of early psychosis and the severity of psychotic symptoms have resulted in a proliferation of studies on this issue.... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The implications of cannabis use in the onset of early psychosis and the severity of psychotic symptoms have resulted in a proliferation of studies on this issue. However, few have examined the effects of cannabis use on the cognitive symptoms of psychosis (i.e., neurocognitive functioning) in patients with first-episode psychosis (FEP). This systematic review and meta-analysis aim to assess the neurocognitive functioning of cannabis users (CU) and nonusers (NU) with FEP.
METHODS
Of the 110 studies identified through the systematic review of 6 databases, 7 met the inclusion criteria, resulting in 14 independent samples and 78 effect sizes. The total sample included 304 CU with FEP and 369 NU with FEP. The moderator variables were age at first use, duration of use, percentage of males, and age.
RESULTS
Effect sizes were not significantly different from zero in any neurocognitive domain when users and NU were compared. Part of the variability in effect sizes was explained by the inclusion of the following moderator variables: (1) frequency of cannabis use (β = 0.013, F = 7.56, p = 0.017); (2) first-generation antipsychotics (β = 0.019, F = 34.46, p ≤ 0.001); and (3) country where the study was carried out (β = 0.266, t = 2.06, p = 0.043).
CONCLUSIONS
This meta-analysis indicates that cannabis use is not generally associated with neurocognitive functioning in patients with FEP. However, it highlights the deleterious effect of low doses of cannabis in some patients. It also stresses the importance of the type of antipsychotic prescription and cannabis dose as moderator variables in the neurocognitive functioning of CU with FEP.
Topics: Antipsychotic Agents; Cannabis; Humans; Marijuana Abuse; Mental Status and Dementia Tests; Psychotic Disorders
PubMed: 32093788
DOI: 10.1192/j.eurpsy.2019.9