Paper: New onset mental illness: analysis by occupation and health costs

Author(s) and Affiliation(s):
Nicola Cherry, University of Alberta
Jeremy Beach, University of Alberta
Igor Burstyn, Drexel University, Philadelphia, PA and University of Alberta
Day/Time: Saturday at 14:00
Room: Ballroom, 2nd Floor

To identify occupations and industry groups in Alberta with higher than expected incidence of physician-diagnosed affective disorder (anxiety/depression) substance abuse (alcohol/drugs) or psychosis. The pattern of health-care costs associated with such mental disorders and their relation to WCB claims are also examined.


An approach previously used in the study of new onset adult asthma [1] has been adopted. Mental illness data and cost data were obtained from administrative health records and linked by personal health number (PHN) to a databank of more than 1,000,000 WCB claims (for all causes) in Alberta from 1996-2005. Subjects whose PHN was missing or invalid in the WCB record were excluded, as were those not resident in the 5 fiscal years prior to the claim. Diagnoses of mental ill-health in the 12 months prior to the WCB claim were examined. Only those with no record of illness (for each condition) in the 3 years prior to the 12 month "lead in" were included in the analysis of "new onset" disease. Costs of health care in each of the 3 years prior to and following the "new onset" health claim were computed.


Some 600,000 subjects (varying slightly between diagnoses) were available for these analyses, with an incidence for affective disorders of 7.8% (male 6.5%; female 13.1%), substance abuse 1.5% (male 1.5%; female 1.2%) and psychosis 0.7% (male 0.6%; female 0.9%). Analysis by occupation indicated that 17 occupations (coded to 4 digits) were at increased risk of new onset affective disorders, 11 of new onset substance abuse and 6 of new onset psychosis. Of concern was the presence of increased risks of new onset affective disorders and psychoses among community welfare workers and of substance abuse amongst locomotive drivers, although these may in part reflect selective employment and testing schedules. Non-mental health costs increased importantly in the year before the incident mental health diagnoses and continued to be raised for the following 12 months. Among those with WCB claims, the peak in costs prior to diagnosis was higher and, for women, continued to climb.


The method previously applied to new onset asthma has allowed analysis of the distribution of new onset physician-diagnosed mental illness among occupations, although job changes and unemployment following diagnosis of disabling disease complicates interpretation of some results. The interaction between mental illness and WCB claims on heath-care costs in women deserves further analysis.


1 Cherry NM, Beach J, Burstyn I, Fan X, Guo N, Kapur N. Data-linkage to estimate the extent and distribution of occupational disease: new onset adult asthma in Alberta, Canada. American Journal of Industrial Medicine 52: 831-40 (2009).