Degree Name

Doctor of Public Health


Graduate School of Public Health


Studies from overseas, predominantly the USA, indicate that patients with severe mental illness (SMI) have elevated risks for sexually transmitted infections (STIs) and blood borne viruses (BBVs). Findings indicate a need for local research to clarify whether there are similarly elevated risk factors, STI/BBV infections and heightened risk for patients with SMI, in Western Sydney, Australia.

Identify the level of risk factors, prevalent STIs or BBVs, and correlates of infection based on risk factor history, as well as explore the role of an SMI diagnosis. Describe the practices and characteristics of psychiatrists caring for patients with SMI, specifically their knowledge, attitudes, and behaviours (KAB) regarding STIs and BBVs, as well as assess the determinants of STI/BBV testing behaviours to identify the potential risk for patients.

The thesis explored the risk regarding STIs or BBVs for patients with SMI with a literature review and two studies. The systematic literature review identified potential risk factors and aided the design of the subsequent studies. Study One was based on structured interviews and biological samples from 95 participants with SMI, inpatients at a large psychiatric hospital, and referred to the study by their attending psychiatrist. The study described and compared sexual and substance use behaviours (including injecting drug use), risk partners, and other risks (such as healthcare and incarceration), as well as the prevalence of STI and BBV infections, based on self-report and/or biological sample result. Risks and infection prevalence were compared to Australian population data. In addition, serology testing and infection prevalence rates for all 1791 admitted Cumberland Hospital patients during the study period were assessed. Descriptive, bivariate, and multivariate analyses were conducted to assess predictors for infection risk. Study Two, a KAB psychometric survey with Likert scales, evaluated 35 psychiatrists working in western Sydney, regarding STIs and BBVs. Descriptive comparisons with GPs and multivariate analyses of psychometric measures were undertaken, exploring pathways to better behaviours assessing patients’ risk for infection.

Study One found that patients with SMI had elevated risk factors (sexual, substance use and incarceration), STI and BBV rates, and statistically significant elevated risk compared to the Australian population, despite a small referred participant group. Patients were at risk because of their own and their partners’ involvement in risk behaviours. HIV (2.5%) was not as prominent, but self-reported STIs (49%), HCV exposure (26%) and HBV exposure (16%) were significant findings. As well, Cumberland Hospital data indicate low screening but with high overall seroprevalence for HCV (5%) and HBV exposure (6%). Infections were not new but many patients were unaware of past exposures or testing, indicating suboptimal STI/BBV healthcare. HCV risk for injecting drug users was higher than injectors from the Australian population, despite similar IDU risk activities. HCV rates and risks were elevated for patients without an IDU history when compared to the stratified Australian population. Elevated HCV risk was possibly associated with the presence of SMI. At multivariate analysis HCV exposure was predicted by “IDU ever” and “incarceration ever”. Self-reported STIs were predicted by “marijuana use ever” or “sex ever with an IDU partner”. Patients with SMI and their partners (often with SMI or met in hospital), may be a unique risk network, with frequent and riskier sexual and drug use activities within this network. SMI risk may be because of psychiatric factors, limited socialisation options and poorer access to healthcare. Study Two, though a small KAB survey of psychiatrists, explained the poor referral to Study One and confirmed the suboptimal STI/BBV healthcare for patients. Participants were slightly older and specialist consultant psychiatrists compared to the pool of available psychiatrists. Overall psychiatrists had good knowledge and attitudes compared to general practitioners (GPs), but there was a lack of screening behaviours for STIs or BBVs, particularly for HCV. Psychiatrists “newer” to the specialty had better HCV knowledge and those “well-informed” reported better HCV screening behaviours. The psychometric multivariate predictors for HCV screening behaviours were HCV referral knowledge and attitudes to HCV patients.

Patients with SMI are at risk for STIs and BBVs and are likely part of a risk SMI network with elevated risk behaviours, risk partners and STI/BBV infections. This SMI network of inpatients may be a closed network and without current new infections. The predominant risks in the network are substance use and incarceration risks by individuals and their partners, and possibly an SMI diagnosis, though this role requires further elucidation. Future studies should assess choices of IDU partners and their risk as well as young people first diagnosed with SMI, who are at risk for new STI or BBV diagnosis. Effective healthcare should include broader STI/ BBV education, prevention, screening and management for patients with SMI. Of particular concern are the high HCV rates, which will add to patients’ health burden with possible liver disease. SMI creates a unique risk network, deserving consideration as a priority group and requiring targeted and holistic healthcare.