New research led by Dr James Kirkbride from the PsyLife group, Division of Psychiatry, UCL, has shown how psychosis risk varies in more rural populations than previously studied in England. The findings, published last week in the American Journal of Psychiatry, reveal that rural regions see a significant rate of new cases of psychotic disorder in their populations. This is important because service planners need to ensure all people developing a first episode of psychosis can get quick, timely access to specialist mental health services such as Early Intervention teams.
The study was conducted in the East of England, in three counties – Cambridgeshire, Norfolk and Suffolk – and tried to identify all young people (aged between 16 and 35 years old) presenting to mental health services for the first time due to psychosis over a 3.5-year period. During this time, the study identified over 680 people who met diagnostic criteria for first episode psychosis living in this region, corresponding to an incidence rate of 34 new cases per 100,000 people per year.
The study also revealed that the risk of developing psychosis varied by important characteristics of both individuals and their environments. For example, although the study was conducted in a more rural setting than many previous epidemiological studies of this type , the authors found that the rate of disorder still varied according to how densely populated and deprived the environment was. Rates of psychotic disorder were relatively stable in most parts of the region, but rose in the most deprived and most densely populated regions. While this data is in keeping with earlier research , the study extends previous knowledge by suggesting that there may be a threshold effect in operation; below a certain level of population density or deprivation, there is no increase in risk, but once a certain level is reached, risk begins to shift. This research has not previously been possible in studies which have tended to be conducted in more urban environments.
The study also found variation by individual level factors. As previously established, men were almost twice as likely to experience a first episode of psychosis than women, particularly in their late teens and early twenties when risk is highest for both sexes. There was some evidence that rates were also raised in black and minority ethnic groups, but another paper from the same study will address this issue in more detail, and is currently under review.