Research Location: St Paul's Hospital

HIV/AIDS continues to be a major health issue in Canada, twenty-five years after the first cases were reported. About 58,000 Canadians, including 13,000 BC residents, are infected with HIV (the human immunodeficiency virus that leads to AIDS), and the incidence appears to be rising. A rough estimate sets the medical costs of caring for people with HIV/AIDS at more than $800 million a year. But rapid treatment advances make medical costs a moving target. Karissa Johnston is using the computer simulation model she developed in her earlier MSFHR-funded research to more accurately estimate the annual and lifetime medical costs of treating people infected with HIV. Johnston has designed a series of modules to measure the amount of HIV virus in peoples’ bloodstream (called the viral load) over their lifetime, their initiation and adherence to antiretroviral medications, their use of health services, and their survival time with different treatment regimes. As new treatments or data become available, individual modules can be updated without affecting the others. This information can help health care providers assess the costs and effectiveness of different treatment options. For example, antiretroviral medications successfully suppress viral load, reducing the risk of passing the infection during a sexual encounter. Even though the medications are costly, this tool will show if they ultimately result in costs savings due to a reduction in new infections.

In 1997, congestive or chronic heart failure (CHF) was the primary cause of death in British Columbia and in 2000, it was the most common cause of hospitalization for Canadians over the age of 65. Multidisciplinary interventions, including education, follow up and self-management strategies have been shown to improve quality of life and decrease subsequent hospital admissions among people with CHF. However, up to 50 per cent of hospital readmissions for CHF occur because patients have not learned to manage and monitor their condition effectively. Biljana Maric’s research is investigating the feasibility of Internet-based self-monitoring for CHF patients. Participants will log on to the study website each morning, enter their current body weight and answer five questions about their health status and any symptoms they are experiencing. A nurse will log on to a secure database to monitor responses and follow up with participants when responses trigger an alert. Biljana’s study will examine patient and staff uptake, and assess the impact of the program on patient quality of life and self care. If adopted, Internet monitoring of heart patients could decrease the health care costs associated with heart failure readmissions, alleviating some of the financial burden on the health care system while improving patient health outcomes.

The economic model of rational addiction was a breakthrough in the economic theory of consumption of addictive substances. This model’s aim is to reliably estimate an addict’s change in consumption of an addictive substance due to a change in the drug’s price or the price of another drug to which the individual is addicted. Polydrug abuse within populations of heroin addicts has been observed within health services research literature for some time. Suggestions have been made to target treatment interventions and outcome assessment to multiple drugs, rather than a single drug in clinical trials involving substance abusers. Despite this, relatively little epidemiological research has been carried out to evaluate the effectiveness of different modes of treatment for drug abuse in polydrug addicts. Bohdan Nosyk is researching whether individuals addicted to more than one substance (e.g. heroin and cocaine) display some association in their consumption patterns of these substances. If there is a significant association in consumption, focusing treatment on one addiction may be ineffective given the increase in consumption within the other (untreated) drug addiction. This study will survey individuals addicted to multiple drugs residing in Vancouver’s Downtown Eastside to determine the relationship between illicit drug prices and consumption. Research into the addicted illicit drug consumer’s behaviour – in particular, how the consumer substitutes between substances and which drugs tend to complement one another – will provide policy-makers with evidence on which to base future directions in the treatment for addictive substance abuse.

A transient ischemic attack (TIA) occurs when there is a temporary disruption of blood supply to the brain. Damage from a TIA is temporary and reversible, but the experience is an important warning symptom for stroke, which is a major cause of death and long-term disability. Patients have a five to ten per cent risk of having a stroke within a week of a transient ischemic attack. Patients with TIA symptoms often go to the emergency department for evaluation, but there is no universally accepted strategy for managing TIA in B.C. Emergency Departments (EDs). A major challenge has been the lack of a system for determining which patients are at high risk for having a stroke and warrant urgent investigation and treatment. Dr. Devin Harris is evaluating the effectiveness of a clinical guideline for standardizing TIA care in EDs. This evidence-based guideline is being implemented as a pilot project in six B.C. emergency departments and will then be expanded to all 92 EDs in the province. Devin is examining physician adherence to the guideline and the impact on patient outcomes. This information will be used to develop a model for predicting which patients are at high risk of stroke after TIA, leading to better preventive and treatment options.