Rise in Psychotic Disorder Diagnoses Among Recent Generations, Study Finds
A recent study reveals an increase in the diagnosis of psychotic disorders, including schizophrenia, among individuals born in more recent generations. This trend is also accompanied by diagnoses occurring at younger ages. The research, which encompassed over 12 million people born between 1960 and 2005, meticulously tracked new diagnoses of psychotic disorders from 1993 to 2023. During this three-decade period, a total of 152,587 individuals received such a diagnosis.
Key Findings
- The rate of new psychotic disorder diagnoses began to rise notably for those born in the 1980s and later.
- Individuals born between 2000-2004 showed an estimated 70% higher rate of new psychotic disorder diagnoses compared to those born between 1975-1979.
- The total number of people diagnosed with a psychotic disorder by age 30 increased by 37.5% for those born between 1990-1994 compared to those born between 1975-1979.
- The incidence rate of psychotic disorders for individuals aged 14 to 20 increased by 60%, from 62.5 to 99.7 per 100,000.
- The incidence of schizophrenia was 70% higher among Ontarians born in 2000-2004 compared to those born in 1975-1979.
- The total number of people diagnosed with a psychotic disorder by ages 20 and 30 were 74.1% and 37.5% higher, respectively, for those born in 1990-1994 compared to 1975-1979.
Dr. Daniel Myran commented on the significant impact of these conditions.
"Psychotic disorders can significantly affect a person's mental and physical health, education, work, and relationships."
He further suggested that while some observed increases might reflect improved care and earlier diagnosis, these patterns also raise concerns about generational changes in exposure to various risk factors.
"The specific drivers behind these changes are not yet fully understood and are likely multi-faceted," Dr. Myran emphasized, highlighting the importance of understanding these trends for prevention and early support.
Risk factors such as early life substance use and older-aged parents were mentioned as potential contributors to the observed rise in psychotic disorders.
Dr. Marco Solmi, a co-author of the study, noted the consistency with international research.
"Some international studies suggest an increase in schizophrenia and other psychotic disorders among young people, possibly linked to increased substance use."
He underscored the unique contribution of this particular research:
"This study is the first to examine recent birth cohorts in North America."
Study Limitations
One limitation of the study was the exclusion of individuals born in the 1960s and early 1970s who developed psychosis in early adulthood but did not interact with the health system. These individuals were not included in the cumulative estimates.
The study, titled "Incidence of psychotic disorders by birth cohort: a population-based cohort study in Ontario, Canada," was published in the February issue of CMAJ.