Amid growing decriminalisation of cannabis use, a new study warns that daily cannabis use, especially of high potency, is strongly linked to the risk of developing psychosis, a mental disorder characterised by a disconnection from reality.
The findings, published in the journal the Lancet Psychiatry, are consistent with previous studies showing smoking pot with a high concentration of THC — over 10 per cent of the psychoactive substance within cannabis — has more harmful effects on mental health than the use of weaker forms.
“As the legal status of cannabis changes in many countries and states, and as we consider the medicinal properties of some types of cannabis, it is of vital importance that we also consider the potential adverse effects that are associated with daily cannabis use, especially of high potency varieties,” said lead author of the study Marta Di Forti from King’s College London.
The new study looked at 11 sites across Europe and Brazil. First, the researchers estimated the prevalence of psychosis by identifying individuals with first episode of psychosis, presented to mental health services between 2010 and 2015.
Second, they compared 901 patients with first episode of psychosis with 1,237 healthy matched controls to understand the risk factors associated with psychosis.
The researchers collected information about participants’ history of cannabis use and other recreational drugs.
Across the 11 sites, people who used cannabis on a daily basis were three times more likely to have a diagnosis of first episode psychosis, compared with people who had never used cannabis, the findings showed.
This increased to five times more likely for daily use of high potency cannabis. (IANS)
A drug that curbs delusions in Parkinson’s patients did the same for people with Alzheimer’s disease and other forms of dementia in a study that was stopped early because the benefit seemed clear.
If regulators agree, the drug could become the first treatment specifically for dementia-related psychosis and the first new medicine for Alzheimer’s in nearly two decades. It targets some of the most troubling symptoms that patients and caregivers face — hallucinations that often lead to anxiety, aggression, and physical and verbal abuse.
Results were disclosed Wednesday at a conference in San Diego.
Unmet need for treatment
“This would be a very important advance,” said one independent expert, Dr. Howard Fillit, chief science officer of the Alzheimer’s Drug Discovery Foundation.
Although the field is focused on finding a cure for dementia and preventing future cases, “there is a huge unmet need for better treatment” for those who have it now, said Maria Carrillo, the Alzheimer’s Association’s chief science officer.
The drug is pimavanserin, a daily pill sold as Nuplazid by Acadia Pharmaceuticals Inc. It was approved for Parkinson’s-related psychosis in 2016 and is thought to work by blocking a brain chemical that seems to spur delusions.
About 8 million Americans have dementia, and studies suggest that up to 30% of them develop psychosis.
“It’s terrifying,” said Dr. Jeffrey Cummings of the Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas. “You believe that people might be trying to hurt you. You believe that people are stealing from you. You believe that your spouse is unfaithful to you. Those are the three most common false beliefs.”
How the study worked
He consults for Acadia and helped lead the study, which included about 400 people with dementia and psychosis. All were given a low dose of the drug for three months, and those who seemed to respond or benefit were then split into two groups. Half continued on the drug and the others were given dummy pills for six months or until they had a relapse or worsening of symptoms. Neither the patients nor their doctors knew who was getting what.
Independent monitors stopped the study when they saw that those on dummy pills were more than twice as likely as those on the drug to relapse or worsen — 28% versus nearly 13%.
There were relatively few serious side effects — 5% in the drug group and 4% in the others. Headaches and urinary tract infections were more common among those on the drug. Two deaths occurred, but study leaders said neither was related to the drug.
Carrillo said the study was small, but the drug’s effect seemed large, and it’s not known whether the federal Food and Drug Administration would want more evidence to approve a new use.
Risk of death
Current anti-psychotic medicines have some major drawbacks and are not approved for dementia patients.
“They’re often used off label because we have very few other options,” Fillit said.