Study reveals ethnic differences in mental illness severity when hospitalized

Chinese and South Asian patients in Ontario experience more severe mental illness at the time of hospital admission than other patients, according to a new study that examined the association between illness severity and ethnicity.

The population-based study, published earlier this month in the Journal of Clinical Psychiatry, was led by researchers at the Centre for Addiction and Mental Health (CAMH) and the Institute for Clinical Evaluative Sciences (ICES). The study represents the largest and most rigorous examination of mental illness severity among Asian populations living in a western country.

"We found that, when compared to patients from other populations, Chinese and South Asian patients were on average much sicker by the time they got to hospital," says Dr. Maria Chiu, principal investigator and scientist at ICES. "While Chinese and South Asian people make up the two largest ethnic minority groups in Canada, to date research on mental illness in these groups has been limited."

Using a database that houses information on adult inpatients in designated mental health beds across all Ontario hospitals, the research team analyzed information on over 133,000 patients hospitalized for psychiatric conditions, such as schizophrenia, bipolar disorder and depression, between 2006 and 2014. To determine mental illness severity, the team looked at four measures: involuntary admissions, aggressive behaviors, and the number and frequency of psychotic symptoms (including hallucinations, delusions, and abnormal thought process).

"Our analysis shows that involuntary admissions were much more common among these ethnic minority groups, with Chinese patients being 80 per cent and South Asian patients being 31 per cent more likely to be admitted involuntarily," says Dr. Chiu. Involuntary hospitalization is an important indicator of illness severity because it typically means that the illness has progressed to the point where both safety and an individual's insight into the impact of their illness are of concern, she notes.

Dr. Chiu hypothesizes that stigma and family dynamics could be factors influencing why Chinese or South Asian people might delay treatment for mental illness. "While Asian people tend to have strong family support, they may also be more likely to experience stigma. Families may try to cope and keep the illness within the family until there is no choice but to go to hospital. Reducing stigma and augmenting culturally sensitive mental health services could help reach people sooner," she says.

Both Chinese and South Asian patients were significantly younger than patients from other populations being hospitalized and were more likely to experience one or more psychotic symptoms, with 55 per cent of Chinese and 49 per cent of South Asian patients exhibiting at least one psychotic symptom, compared to 38 per cent of other populations with these diagnoses.

While the experience of immigration is often linked to the development and severity of mental illness, this study showed similar severity in both immigrants and Canadian-born patients of Chinese and South Asian descent, suggesting that ethnicity itself is a predictor.

"Like any other health condition, the longer mental illness goes without treatment, the more difficult it can be to get people back on track," says Dr. Paul Kurdyak, psychiatrist and researcher with CAMH's Institute for Mental Health Policy Research and lead scientist for the ICES Mental Health and Addictions Research Program. "This study highlights that ethnicity and culture are factors that should be considered when developing outreach strategies and treatment approaches, particularly at earlier stages before a patient's illness worsens and hospitalization becomes necessary."