Measuring health-related quality-of-life for Alzheimer’s disease using the general public

Little research exists to indicate whether the general public can provide proxy health-related quality-of-life (HRQoL) estimates
for persons with Alzheimer’s disease (AD). We investigated (1) whether the general public can differentiate between mild,
moderate, and severe AD and (2) whether the general public’s proxy HRQoL estimates are correlated with current health status.

We conducted computer-assisted personal interviews. The computer randomly assigned each participant to read a vignette describing
mild, moderate, or severe AD. Participants answered the EQ-5D-5L and Quality-of-life-Alzheimer’s Disease (QoL-AD), while imagining
living in the health state described in their assigned vignette. Participants also answered the EQ-5D-5L based on their health
state at the time of the interview.

We interviewed 100 participants. EQ-5D-5L utilities were 0.7413 (mild), 0.6159 (moderate), and 0.4456 (severe) (P < 0.001). Mean QoL-AD scores were 32.5 (mild), 24.0 (moderate), and 21.8 (severe) (P < 0.0001 for severe vs. mild, moderate vs. mild; P > 0.05 for severe vs. moderate). Participants’ EQ-5D-5L utility scores were weakly correlated (r ≤ 0.28) across both administrations of the instrument.

The general public can differentiate between the three stages of AD, and their HRQoL estimates for AD are weakly correlated
with their current health status.