The Essential and Potentially Inappropriate Use of Antipsychotics across Income Groups: An Analysis of Linked Administrative Data

Abstract

Objective: To examine the essential and potentially inappropriate use of antipsychotics across income groups. Method: Linked health, pharmaceutical use, and income data from British Columbia were analyzed to examine antipsychotic use in 2 study cohorts. In the first cohort, the essential use of antipsychotics was assessed among adults who had a recorded diagnosis of schizophrenia in a 2-year period, 2004–2005. In the second cohort, potentially inappropriate use of antipsychotics was examined in people with no recorded diagnosis of schizophrenia or bipolar disorders in 2004–2005. The second cohort was also composed exclusively of seniors with a dementia-related diagnosis who are either in long-term care or living in the community. Income-related differences in antipsychotic use in these 2 cohorts were assessed using logistic regression, controlling for health and sociodemographic characteristics known to influence medicine use. Results: Among adults, the prevalence of essential antipsychotic use was high (85%), with higher odds of use evident among those in the middle-income group. Among seniors, the prevalence of potentially inappropriate antipsychotic treatment is 23%, with prevalence higher in long-term care (56%) than in the community (13%). No income-related differences were found in long-term care; however, in the community, higher odds of use were found in low-income seniors. Conclusion: People from low-income households have slightly lower levels of essential antipsychotic use and are more likely to receive potentially inappropriate antipsychotic treatment.