Estimated Quality-Adjusted Life-Year Associated with the Degree of Activities of Daily Living in Patients with Alzheimer's Disease

BACKGROUND/AIMS The quality-adjusted life-year (QALY) and health state utility values (HSUVs) are major quality of life scales that are used for the analyses of health economics of diseases such as Alzheimer's disease (AD). In Japan, the most common dementia disease is AD with cerebrovascular diseases (CVD), followed by 'pure' AD. There is a need to reconsider QALY and HSUVs in the context of activities of daily living (ADL) levels in AD and AD with CVD. METHODS Studies on QALY and HSUVs based on ADL levels in AD were identified using a PubMed search. HSUVs were estimated in AD patients with ADL levels A (independent walking and eating), B (some problems with walking but sitting without assistance), and C (confined to bed). These three ADL levels correspond approximately to the stages of Mobility on the EQ-5D. RESULTS There has been no previous report on HSUVs related to the level of physical activity of patients with AD. From the previous reports and EQ-5D, we estimated that the HSUVs of pure AD and AD with CVD for ADL levels A, B, and C were 0.61 and 0.58, 0.53 and 0.28, and 0.19 and 0.05, respectively. CONCLUSION Effects of ADL should be considered during the decision making process in health policy for dementia care in Japan.