The issues are also explored in an accompanying Comment and Editorial, with the Editorial concluding: “Governments would do well to invest in sustained and effective education campaigns on the risks to health of taking cannabis.”
Cannabis, or marijuana, is the most commonly used illegal substance in most countries, including the UK and USA. Up to 20% of young people now report use at least once per week or heavy use (use on more than 100 occasions).
Dr Theresa Moore, University of Bristol, and Dr Stanley Zammit, Cardiff University, Wales, and colleagues did a meta-analysis of 35 studies, dated up to 2006, to assess whether there was evidence to connect cannabis use to occurrence of psychotic or mental health disorders.
They found that individuals had used cannabis ever were 41% more likely than those who had never used the drug to have any psychosis. The risk increased relative to dose, with the most frequent cannabis users more than twice as likely to have a psychotic outcome. Depression, suicidal thoughts, and anxiety outcomes were examined separately, and findings for these outcomes were less consistent, with fewer attempts made to address non-causal explanations than for psychosis.
The authors say that recent estimates of the proportion of young adults and adolescents who have ever used cannabis is 40%. If having ever used cannabis increases the risk of a psychotic outcome by 41%, about 14% of psychotic outcomes in young adults in the UK would not occur in cannabis were not consumed.
The authors say: “We have described a consistent association between cannabis use and psychotic symptoms, including disabling psychotic disorders.”
They conclude: “Despite the inevitable uncertainty, policymakers need to provide the public with advice about this widely used drug. We believe that there is now enough evidence to inform people that using cannabis could increase their risk of developing a psychotic illness later in life.”
In the accompanying Comment, Drs Merete Nordentoft and Carsten Hjorthøj, Copenhagen University Hospital, Denmark say: “In the public debate, cannabis has been considered a more or less harmless drug compared with alcohol, central stimulants, and opioids. However, the potential long-term hazardous effects of cannabis with regard to psychosis seem to have been overlooked, and there is a need to warn the public of these dangers, as well as to establish a treatment to help young frequent cannabis users.”
Tony Kirby | alfa
Hot cars can hit deadly temperatures in as little as one hour
24.05.2018 | Arizona State University
3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
25.05.2018 | Event News
02.05.2018 | Event News
13.04.2018 | Event News
25.05.2018 | Event News
25.05.2018 | Machine Engineering
25.05.2018 | Life Sciences