University Of QueenslandSchizophrenia is claimed to be a grave disorder that may affect around 1 in a 100 Australian. It is also the time when the brain appears to be most susceptible to cannabis.

The scientists from UQ’s Queensland Brain Institute and School of Population Health have apparently discovered that young adults who use cannabis from an early age appear to have three times more chances to suffer from psychotic symptoms.

The study included over 3,800 21-year-olds. The study divulged that those who use cannabis for six or more years appear to have a bigger threat of developing psychotic disorders or the isolated symptoms of psychosis like hallucinations and delusions.

Lead investigator Professor John McGrath, commented, “This is the most convincing evidence yet that the earlier you use cannabis, the more likely you are to have symptoms of a psychotic illness. We were able to look at the association between early cannabis use and later psychotic symptoms in siblings. We know they have the same mother, they most likely have the same father and, because they’re close in age, they share common experiences, which allows us to get a sharper focus on the specific links between cannabis and psychosis – there is less background noise.”

He added, “Looking at siblings is a type of natural experiment – we found the same links within the siblings as we did in the entire sample. The younger you are when you started to use cannabis – the greater the risk of having psychotic symptoms at age 21. This finding makes the results even stronger. The message for teenagers is: if they choose to use cannabis they have to understand there’s a risk involved. Everyone takes risks every day – think of the sports we play or the way we drive – and people need to know that we now believe that early cannabis use is a risk for later psychotic illness.”

The study is said to be based on a group of children born at Brisbane’s Mater Hospital during the early 1980s. They have been trailed for nearly 30 years. The study also apparently encompassed the outcomes of around 228 sets of siblings.

The study was published in the Archives of General Psychiatry.