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Social Psychiatry and Psychiatric Epidemiology

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01-12-2016 | Original Paper

Adherence to antipsychotic medication among homeless adults in Vancouver, Canada: a 15-year retrospective cohort study

Authors: Stefanie N. Rezansoff, A. Moniruzzaman, S. Fazel, R. Procyshyn, J. M. Somers

Published in: Social Psychiatry and Psychiatric Epidemiology | Issue 12/2016

Abstract

Purpose

The purpose of this study was to investigate the level of adherence to antipsychotic prescription medication in a well-defined homeless cohort over a 15-year period. We hypothesized that adherence would be well below the recommended threshold for clinical effectiveness (80 %), and that it would be strongly associated with modifiable risk factors in the social environment in which homeless people live.

Method

Linked baseline data (including comprehensive population-level administrative prescription records) were examined in a subpopulation of participants from two pragmatic-randomized trials that investigated Housing First for homeless and mentally ill adults. Adherence to antipsychotic medication was operationalized using the medication possession ratio. Multivariable logistic regression was used to estimate effect sizes between socio-demographic, homelessness-related and illness factors, and medication possession ratio.

Results

Among the 290 participants who met inclusion criteria for the current analysis, adherence to antipsychotic prescription was significantly associated with: history of psychiatric hospitalization; receipt of primary medical services; long-acting injectable antipsychotic formulations; and duration of homelessness. Mean medication possession ratio in the pre-randomization period was 0.41. Socio-demographic characteristics previously correlated with antipsychotic non-adherence were not significantly related to medication possession ratio.

Conclusions

This is the first study to quantify the very low level of adherence to antipsychotic medication among homeless people over an extended observation period of 15 years. Each of the four factors found to be significantly associated with adherence presents opportunities for intervention. Strategies to end homelessness for this population may represent the greatest opportunity to improve adherence to antipsychotic medication.

Available only for authorised users

See: http://www2.gov.bc.ca/gov/content/health/health-drug-coverage/pharmacare-for-bc-residents/pharmanet.

PharmaNet introduced a Maximum Days’ Supply policy in 1996.

Beginning January 1, 1996.

Residents of British Columbia who are diagnosed with mental illness who demonstrate clinical and financial need are eligible for the provincial no-charge psychiatric medication plan. Income assistance recipients are also eligible for 100 % coverage of eligible prescription costs.

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Title: Adherence to antipsychotic medication among homeless adults in Vancouver, Canada: a 15-year retrospective cohort study
Authors: Stefanie N. Rezansoff
A. Moniruzzaman
S. Fazel
R. Procyshyn
J. M. Somers
Publication date: 01-12-2016
Publisher: Springer Berlin Heidelberg
Published in: Social Psychiatry and Psychiatric Epidemiology / Issue 12/2016
Print ISSN: 0933-7954
Electronic ISSN: 1433-9285
DOI: https://doi.org/10.1007/s00127-016-1259-7

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Adherence to antipsychotic medication among homeless adults in Vancouver, Canada: a 15-year retrospective cohort study

Abstract

Purpose

Method

Results

Conclusions

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Abstract

Purpose

Method

Results

Conclusions

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