The risk increased to almost five times more likely in those who smoked high-potency marijuana on a daily basis.
"Cannabis carries severe health risks and users have a higher chance of developing psychosis".
In the new study, the researchers found that about 30 percent of patients with psychosis reported daily marijuana use, compared with just 7 percent of controls (people without psychosis); and 37 percent of patients reported high-potency marijuana use, compared with 19 percent of controls. They compared these patients with more than 1,200 random folks who'd never been diagnosed with psychosis.
Potent cannabis types with more than 10 percent of the psychoactive ingredient THC were linked to a five times greater risk.
Adjusted for other factors, people who used cannabis daily were three times as likely to be diagnosed with an initial episode of psychosis, and people who used high-potency cannabis were about five times more likely to develop psychosis, according to the research.
"We asked people if they used cannabis, when did they start using it and what kind of cannabis", explains study author Marta Di Forti, a psychiatrist and clinician scientist at King's College London.
A third of psychosis cases in London are the result of smoking skunk, according to a study that underlines the danger of super-strength cannabis. In London, 2 in 10 cases were linked to daily use, while 3 in 10 were linked to high-potency use. The fact that consuming high-THC cannabis products has a greater risk is concerning, Lisdahl says, because these products are more common in the market now.
More studies using different designs "could help us to triangulate evidence and get a better idea of whether it's truly a causal effect", Gage said.
Fed sees no rate hikes in 2019, sets end to asset runoff Some analysts believe the next rate move could be a cut later this year if the economy slows as much as some fear it might. The Fed's primary responsibilities consist of maximizing employment in the USA and maintaining long-term price stability.
Boeing CEO: 'We know lives depend on the work we do' The CEO of Boeing has announced that the U.S. aircraft maker will soon release a software update for its troubled 737 MAX jets . In the Lion Air crash, sensors possibly misread the plane's performance and sent the jet into a dive to avoid a phantom stall.
If high-THC cannabis - including strains such as "trainwreck", "gorilla glue", and "hindu kush" - were no longer available, "12 per cent of cases of first-episode psychosis could be prevented across Europe", the researchers calculated. But the new study shows that cities with more easily available high-THC weed do have a higher rate of new diagnoses of psychosis.
The new study is "in line with a lot of research over the last few years showing an association between use of marijuana ... and onset of psychotic illness", said Dr. David Roane, chairman of psychiatry at Lenox Hill Hospital in New York City, who was not involved with the study.
It is the biggest study to look at the impact of marijuana on psychiatric disorders.
Because this was an observational study, it can't prove a direct cause-and-effect link between pot and psychosis, said Suzanne Gage, a psychologist with the University of Liverpool who wrote an editorial accompanying the study.
The Adolescent Brain Cognitive Development study, which is funded by the U.S. National Institutes of Health, is attempting to tease out the various influences, Lisdahl says.
"That could be the thing that tips the scale for some people", she told the AP.
Dr Di Forti said even low-THC cannabis oil, used for epilepsy and MS, should come with a warning of possible mental health effects.
It's a no brainer, but the countries that occupy the bottom of the World Happiness Index are nations ravaged by unrest and war. Nevertheless Israel remains ahead of such countries as the United Kingdom (15), Germany (17) and the U.S. (19).
Manchester United's FA Cup quarter-final defeat by Wolves is a "big step backwards", says interim manager Ole Gunnar Solskjaer . Solskjaer led United on a run of 14 wins from 17 games in all competitions after taking over from Jose Mourinho in December.
You can highlight passages, look up definitions, translate, and adjust the text size all without losing your place. This has a slight change in design, but the major new addition is the inclusion of a built-in front light.
They want to commit to a close post-Brexit economic relationship with the bloc to ease disruption for businesses and citizens. Britain's political chaos has drawn reactions ranging from sympathy to scorn at home and around the world.
However, Netflix has said it will not make its TV shows and movies available through Apple upcoming video offering. Speaking to journalists, Hastings said Netflix prefers to let its customers enjoy its content on its own service.
It is usually caused by repeated injury to the esophagus due to smoke, alcohol, acid reflux and - maybe - hot liquids. The researchers said that it would be "reasonable" to extrapolate their results to other types of hot drink.
The D' Bone Collector Museum biologists who conducted the autopsy said it was "the most plastic we have ever seen in a whale". Ingesting plastic gives whales a false sensation of fullness without providing any of the nutrients they need.
If Google is found not to have done enough, it could see another fine encompassing 5 percent of Alphabet's daily income worldwide. Google's rivals were unable to grow and offer alternative online search advertising intermediation services to those of Google.
That's the game in which the 76ers dropped confetti from the rafters in what ultimately would be their only victory of the series. Rozier, who already has trolled the 76ers for the confetti celebration, did so again after Wednesday's game.
Even if Mueller's final report does not implicate the president in criminal conduct , the investigation was far from fruitless. The attorney general is ultimately the official who decides what, if anything, in the report can become public.
Call of Duty: Mobile Announced for iOS and Android
Not only is there a version of the classic Zombies mode , but even a mobile version of COD's Blackout Battle Royale mode . Those who want to get into Call of Duty: Mobile can pre-register on the game's website for iOS .
Letter points to terror motive in Dutch tram attack
Prosecutors were questioning all three suspects and it wasn't clear when Tanis would be brought before an investigating judge. Police are asking more witnesses who were on the tram to come forward as their investigation into the shooting continues.
Powerball Hits Eighth Largest Jackpot Ever
This includes three players who matched four white ball numbers plus the red Powerball , including one in Hixson. That figure is the largest in seven months dating back to the $687.8 million jackpot won in October 2018.
Sen. Warren Proposes Abolishing Electoral College
Kamala Harris told late night host Jimmy Kimmel on Tuesday night that she's "open to the discussion". Trump had this to say about the electoral college in 2012: it's "a disaster for a democracy".
Trump steps up attacks on late Sen. John McCain
And after McCain died, "I ... gave him the kind of funeral he wanted ... but I didn't get a thank-you", Trump complained. President Trump infamously ripped McCain for being described as a war hero because he was captured.
Records show FBI was probing Michael Cohen long before raid
Since pleading guilty, he has publicly blamed Trump for his downfall, calling his former boss a con man, a racist, and a cheat. Cohen was not a registered lobbyist, nor had he registered under the Foreign Agents Registration Act, authorities alleged.