Health-Related Quality of Life and Cost-Utility Analysis in Islet Transplantation for Type 1 Diabetes
Clinical islet transplants have created excitement with their ability to provide improved blood glucose control for patients with severe type 1 diabetes. However, these patients must trade the difficulties in controlling their labile diabetes with life-long immunosuppression. The full risks and benefits and long-term outcomes of the procedure (known as the ‘Edmonton Protocol') are not fully known, nor are the costs. We are collaborating in a study to assess changes in health-related quality of life (HRQL) in patients undergoing islet transplant procedures. Patients are asked to fill out a battery of HRQL questionnaires at various stages: pre-transplant, mid-treatment (one month after the initial transplant), then one month after the second transplant. Longitudinal data are further collected three, six, 12, 24, and 36, 48, and 60 months after the second transplant. At each interval, patients complete a sociodemographic questionnaire, along with several measures of HRQL, including: the SF-36, the Hypoglycemia Fear Survey, the Health Utilities Index Mark 3 (HUI3), the Immunosuppressant Related Quality of Life (IRQoL), and the Hospital Anxiety and Depression Scale (HADS). By capturing information on both general and transplant-specific HRQL, we hope to assess how patients' themselves feel about the procedure and subsequent treatments.
We are also developing an islet transplant-specific questionnaire to capture the HRQL issues that are unique to this patient population. We are also planning on collecting longitudinal qualitative interviews, in order to assess in greater depth the types of HRQL changes that occur for patients as they move from pre-transplant to post-transplant status.
Using the HUI3 data captured in the HRQL measures, we will then compare the incremental costs of the islet transplant procedure with the outcomes assessed in quality-adjusted life years (QALYs) gained. For the purposes of this incremental cost-utility analysis, we will compare the costs and QALY's for a ‘do-nothing' approach for these patients (i.e., maintain on current insulin therapy for labile diabetes), as well as pancreas alone transplant. We are therefore collecting similar HRQL data on a control group of patients with type 1 diabetes.
Jeff Johnson, James Shapiro, Edmond Ryan, Samantha Bowker and Peter Senior.
Juvenille Diabetes Research Foundation
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