Discrimination of Health States in Follicular Lymphoma with Utilities Derived from the EuroQOL EQ5D Instrument.

Introduction: Health utilities (HU) elicited directly from patients have immediate application in facilitating medical decision-making and cost-effectiveness determinations. Collection of HU using generic health status scales enable comparisons across diseases, but may not be sensitive to variations in health states within a particular disease. The EuroQOL EQ5D is a generic scale that has never been used to generate utilities in a broad spectrum of follicular/indolent lymphoma patients and has not been validated in this context.

Methods: A consecutive, cross-sectional cohort of patients attending an outpatient malignant hematology clinic at a major cancer centre (Toronto, Canada) represented the eligible study population. Patients with a diagnosis of FL or other indolent NHL who consented to the study were asked to complete demographic and disease specific questionnaires in addition to the EuroQOL EQ-5D and Functional Assessment of Cancer Therapy (FACT)-Lymphoma quality of life assessment tools.

Results: Eighty-four patients completed the survey study (>95% response rate). Mean age was 58.7 (+/− 13.8 SD) and 55% were male. Diagnoses included FL (55%), CLL (25%), and other indolent NHL (20%). The majority of patients presented in advanced stage (stage III–IV; 65%) and had received some therapy to date, although 29% were still being observed at the time of survey administration. The mean utility score for the population was 0.84 (+/− 0.24; range 0–1). We evaluated the construct that patients receiving active treatment and those who were not in remission would have lower utility scores. Indeed, utilities were higher in patients being observed (0.91 +/− 0.16) compared to those in first remission (0.84 +/− 0.25), subsequent remissions (0.81 +/− 0.20), or those who were receiving active chemotherapy (0.75 +/− 0.27; p=0.049). Patients who were being followed in ongoing remission also trended to higher health status values (mean 0.88 +/− 0.21) compared to those who were not in remission (0.80 +/− 0.22; p=0.15). Utilities elicited from the EQ5D showed a moderate correlation with a criterion measure of quality of life, the FACT-Lymphoma scale (Spearman correlation coefficient 0.54, p<0.0001).

Conclusions: Utilities from the EQ5D are able to discriminate various health states in patients with follicular and other indolent lymphomas and the scale demonstrates construct and criterion validity in this population. HU scores are particularly sensitive to changes in patient remission and treatment status.