Associations of independent living and labor force participation with impairment indicators in schizophrenia and bipolar disorder at 20-year follow-up

Background: Since the Iowa 500 study, residential and occupational status have been frequently used as indicators of everyday achievements in research on schizophrenia and bipolar disorder. The relationships of residential and occupational status with impairment in multiple domains including physical health indicators across these two diagnoses, however, have rarely been studied. We examined these relationships at the 20-year follow-up assessment of a first-admission sample. Methods: We included 146 participants with schizophrenia and 87 with bipolar disorder with psychosis who participated in the 20-year follow-up of the Suffolk County Mental Health Project. In addition to interviewer-based ratings of employment and residential independence, we examined self-reported impairment derived from the WHODAS, standard measures of current psychopathology, indicators of obesity, as well as performance-based measures of physical and cognitive functioning. Results: Participants with bipolar disorder were more likely to live independently and be gainfully employed; they also performed significantly better on each indicator of impairment apart from balance ability. In both groups, unemployment, but not residential independence, was associated with greater self-reported disability on the WHODAS. Residential independence, gainful employment, and subjective disability were also associated with better physical functioning. Across the two groups, psychiatric symptoms and physical functioning were the major determinants of subjective disability. Discussion: People with psychotic bipolar disorder were more likely to be gainfully employed and living independently than participants with schizophrenia but as a group, much less frequently than population standards. Interventions aimed at physical fitness may have the potential to improve both objective functioning and perceived disability.