Comparison of time trade-off utility with neurocognitive function, performance status, and quality of life measures in patients with metastatic brain disease

Abstract

The objective of this study is to evaluate the concordance between neurocognitive function (NCF), Karnofsky performance status (KPS), quality of life, symptom burden, and time trade-off (TTO) over time. We retrospectively analyzed secondary data from a randomized study of 58 patients who completed tests determining TTO utility with each of the three time horizons (10, 5, and 1 years), NCF, KPS, quality of life (Functional Assessment of Cancer Therapy-Brain (FACT-BR)), and symptoms (MD Anderson Symptom Inventory-Brain Tumor (MDASI-BT)). Multiple linear regression analyses were used to estimate the relationships between TTO utility and other outcome variables, including a time of data collection variable (baseline, 1, 2, 4, 6, 9, 12, 15, 18, 21, and 24 months) to capture within-patient change over time. Significant but weak associations were found between the 10-year TTO utility and FACT-BR scores (p < 0.01), the 10-year TTO utility and MDASI-BT (sleep) scores (p = 0.039), the 5-year TTO utility and FACT-BR scores (p < 0.01), and the 5-year TTO utility and MDASI-BT (sleep) scores (p = 0.039). NCF and KPS scores were not significantly associated with TTO utility. The analysis of within-patient changes over time indicated significant mean group increases in the 10-year TTO utility (p = 0.021) and NCF (HVLT-R Total Recall) scores (p = 0.032); however, KPS score significantly decreased (p < 0.01). Patients’ quality of life and sleep disturbance symptoms have significant but small effects on the patients’ willingness to trade time. The lack of correlation between TTO utility and functional status as well as cognitive function suggests that patients’ preferences for better health and for quantity of life are primarily influenced by the expected length of time until death and not by their current health state.