Thesis Format

Integrated Article

The Prevalence of Multimorbidity among People with Non-Affective Psychotic Disorders 10-Years After First Diagnosis

Myanca D. Rodrigues, The University of Western OntarioFollow

Degree

Master of Science

Program

Epidemiology and Biostatistics

Supervisor

Anderson, Kelly K.

Abstract

Prior research suggests that people with psychotic disorders have an excess risk of individual chronic conditions, however less is known about their risk of co-occurring multiple chronic health conditions; that is, multimorbidity. The overall objective of this thesis was to examine the association between psychotic disorders and multimorbidity using two complementary studies. First, our systematic review and meta-analysis of fourteen studies found that people with psychotic disorders had an increased risk of 2+ chronic conditions relative to those without psychosis (RR=1.69, 95%CI=1.37,2.08). Second, our retrospective matched cohort study found that people with psychotic disorders treated by an early psychosis intervention program (n=439) may have a 26% higher prevalence of multimorbidity relative to people without psychosis (n=1,759), although our findings include the possibility of a null effect (PR=1.26, 95%CI=0.96,1.66). We suggest future research using larger sample sizes and longer follow-up periods to better understand the association between psychotic disorders and multimorbidity.

Summary for Lay Audience

Chronic health conditions such as diabetes, cardiovascular disease and cancer require long-term ongoing management by patients, clinicians, and healthcare systems. Mental illnesses such as depression and schizophrenia are also examples of chronic conditions. Psychosis or the presence of sensory perceptions or false beliefs is present in schizophrenia and other psychotic disorders. Prior research indicates that people with psychotic disorders experience a higher percentage of one other chronic health condition (e.g. diabetes or cancer) as compared to people without psychosis. However, we do not know whether people with psychotic disorders also experience multimorbidity or the co-occurrence of two or more (2+) chronic health conditions, e.g. psychosis in addition to diabetes and cancer. Multimorbidity is challenging for clinicians who provide treatment to patients and for healthcare systems which allocate the appropriate number of resources for patient care. Therefore, it is important to understand multimorbidity so that we can better meet the needs of patients with psychotic disorders. The overall goal of this thesis was to compare the occurrence of multimorbidity between people with psychosis and those without psychotic disorders through two research studies. Our first study pooled findings from fourteen prior research studies and found that people with psychotic disorders may have a higher risk of developing 2+ other chronic health conditions as compared to people without psychosis. Our second study focussed on people with psychotic disorders who were treated by an early psychosis intervention program in London, Ontario. We tracked healthcare records for people with and without psychotic disorders for ten years to estimate the percentage of people who experienced 2+ other chronic health conditions in each of these groups, and we then compared those two estimates. We found that there was a higher percentage of multimorbidity among people with psychotic disorders as compared to people without psychosis. It is recommended that future researchers follow the health records of patients with psychotic disorders for a longer period of time to better estimate multimorbidity.

Recommended Citation

Rodrigues, Myanca D., "The Prevalence of Multimorbidity among People with Non-Affective Psychotic Disorders 10-Years After First Diagnosis" (2020). Electronic Thesis and Dissertation Repository. 7159.
https://ir.lib.uwo.ca/etd/7159