PND39 - Something is Better Than Nothing: The Value of Active Intervention on Stated Preferences for Treatments to Delay Onset of Alzheimer’s Disease Symptoms

Abstract

To quantify the value of active treatment relative to no treatment for Alzheimer’s Disease (AD) apart from specified treatment benefits, tolerability, and adverse-event risks. 1004 older adults in the US completed a web-enabled discrete-choice survey in which they were to suppose that they would develop AD in the future without treatment. Choice tasks presented the option of no treatment or an AD treatment that would extend time with normal memory or time with cognitive impairment prior to developing AD. Treatment benefits were combined with nausea and increased risks of disabling stroke and of death in the first year of treatment. The study design included a dominated-pair validity test where the treatment alternative offered no additional benefit but significant tolerability and serious adverse-event risks. We evaluated the impact of excluding respondents who failed the dominated-pair validity test and those who chose the AD treatment in all 8 questions. A choice model for the full sample with an alternative-specific constant for treatment vs. no treatment was statistically significant (beta=1.16, P=0.036) and a maximum acceptable risk (MAR) of mortality for one more year of normal memory of 13% (CI 9%-17%). A surprising 30% of respondents chose the treatment alternative in the dominated-pair validity test. Excluding these respondents and/or respondents who always chose the treatment alternative eliminated the significant label effect and reduced the MAR by about half. Thus, the value of AD treatment, regardless of efficacy or side effects, is equivalent on average to reducing acceptable treatment risk by about 6%. Patients faced with a terminal condition often are hopeful that treatments that offer little benefit to the average patient will work better in their case. We found significant evidence of this “value of hope” in this study of treatments to delay onset of AD symptoms.