Heavy users of mental health care have substantially different patterns of health care use

The study published in the January issue of Health Affairs is one of the first to look at heavy users of mental health care specifically -- most studies to date have focused on all heavy users.

The study found the average cost of health services used by heavy users of mental health care was more than 30 per cent greater than for other heavy users of health care. Mental health services, including psychiatric hospitalizations and visits to a physician or a psychiatrist, made up the largest portion (about 88 per cent) of the total cost, and services not related to mental health accounted for the remaining 12 per cent.

"Heavy users of mental health care have complex needs, and it's crucial to address their needs through an integrated, multidisciplinary approach," says Dr. Claire de Oliveira, Scientist and Health Economist in Social and Epidemiological Research at CAMH, and lead author on the paper.

Using administrative health care data collected by ICES, the researchers examined health care use by people defined as heavy users based on the costs of the services they used -- also referred to as high-cost users. The study looked at nearly one million high-cost health care users age 18 years or older in Ontario in 2012. Five per cent -- 51,457 people -- were considered to be high-cost mental health care users, defined as people for whom costs for mental health services were at least 50 per cent of their total health care costs.

Understanding which services they use can point to where improvements might occur, both in the delivery of services and in individuals' wellbeing.

Different population characteristics, and high rates of hospitalization

Heavy users of mental health care were younger relative to other high-cost users, and most came from lower-income urban neighbourhoods. People age 18 to 49 made up 58 per cent of heavy users of mental health care and only 24 per cent of other high-cost users. Heavy users of mental health care also tended to be more evenly split among men and women -- 49 per cent were males and 51 per cent were females -- versus other heavy users (42 per cent males and 58 per cent females). Other high-cost users were more likely to have chronic diseases, primarily circulatory and digestive illnesses.

About 64 per cent of heavy users of mental health care had at least one psychiatric hospitalization in 2012. More than 90 per cent had at least one visit to a doctor for mental health care and one or more visits for other health care.

The researchers note that other studies have shown that people who have psychiatric hospitalizations, particularly people with severe mental illnesses such as schizophrenia, have high rates of hospital readmission and low rates of physician visits after they are discharged from a psychiatric hospital stay.

"Our research shows that heavy users of mental health care have substantially different patterns of health care use than other high-costs health care users, representing a different patient population," says Dr. de Oliveira. "Their needs must be considered separately when looking to improve the quality of care for heavy users of health care in general."

Opportunity for early prevention

As a next step, the researchers are developing a predictive model to identify mental health care users at highest risk of future hospitalization. "If we can identify individuals at risk before they become high-cost users of mental health care, this may present an opportunity to provide earlier preventive health care and social services, such as high-support housing units," says Dr. de Oliveira.