We look into 3 studies each of which provide evidence of one hypothesis or another. In the end we conclude that cannabis aggravates already susceptible people's condition who are young users and predominantly male and pushes them into a symptomatic stage of psychosis, rather than causing psychosis in an otherwise normal individual.
It has been demonstrated by many a studies that substance abuse is more prevalent in patients with psychotic disorders than in the general population. What is of debate is whether substance abuse precedes psychotic disorders like schizophrenia and is a risk factor for the disease or whether it is just the fact that people with the disorders tend to misuse the drugs. Alcohol and cannabis are the most commonly abused drugs in the general population as well as in people with mental disabilities. Since the middle of the 20th century, the use of mental state altering drugs has increased. Cannabis use has been on the rise and although many attempts have been made to associate or disassociate it from disorders linked with it, researchers are still debating the full impact cannabis use might have on the public. It is imperative that agreement be achieved on the effects of cannabis so that policies and restriction on community use and definitive treatments can be provided to the affected people.
The exact relation between cannabis use an...
The recent cause of concern is the fact that multiple studies are pointing the finger at the hypothesis that cannabis use leads to schizophrenia. Hickman M et al (2007) in their study have tried to estimate long term patterns of cannabis use in the general population and attempted to and estimate and observe if the schizophrenia rates follow the same pattern. This pattern, if could to be present, they believe could demonstrate that cannabis usage has a direct relationship with schizophrenia as has been proposed by numerous old studies.
"Trends in cannabis use were estimated from a national survey, and the incidence of schizophrenia was derived from surveys in three cities. A difference equation cohort model was fitted against estimates of schizophrenia incidence, trends in cannabis exposure and assumptions on association between cannabis and schizophrenia. The model projects trends in schizophrenia incidence, prevalence and attributable fraction of cannabis induced schizophrenia" (Hickman M et al, 2007). Hickman M et al has shown that over the past few decades cannabis use has gradually, but steadily increased in the young age groups of the society. He argues that if there was a casual relationship between cannabis use and schizophrenia prevalence, then the incidence and prevalence of disease should also show an upwards trend in the younger generation (assuming that all other factors remain constant). But recent studies of epidemiology according to Hickman (2007) suggest that schizophrenia's incidence and prevalence is in a downward trend. Their projections for the future also show a downward or a trend. This pattern contradicts the theory of casual