Desire for predictive testing for Alzheimer’s disease and impact on advance care planning: a cross-sectional study

Abstract

BackgroundIt is unknown whether older adults in the United States would be willing to take a test predictive of future Alzheimer’s disease, or whether testing would change behavior. Using a nationally representative sample, we explored who would take a free and definitive test predictive of Alzheimer’s disease, and examined how using such a test may impact advance care planning.MethodsA cross-sectional study within the 2012 Health and Retirement Study of adults aged 65 years or older asked questions about a test predictive of Alzheimer’s disease (N = 874). Subjects were asked whether they would want to take a hypothetical free and definitive test predictive of future Alzheimer’s disease. Then, imagining they knew they would develop Alzheimer’s disease, subjects rated the chance of completing advance care planning activities from 0 to 100. We classified a score > 50 as being likely to complete that activity. We evaluated characteristics associated with willingness to take a test for Alzheimer’s disease, and how such a test would impact completing an advance directive and discussing health plans with loved ones.ResultsOverall, 75% (N = 648) of the sample would take a free and definitive test predictive of Alzheimer’s disease. Older adults willing to take the test had similar race and educational levels to those who would not, but were more likely to be ≤75 years old (odds ratio 0.71 (95% CI 0.53–0.94)). Imagining they knew they would develop Alzheimer’s, 81% would be likely to complete an advance directive, although only 15% had done so already.ConclusionsIn this nationally representative sample, 75% of older adults would take a free and definitive test predictive of Alzheimer’s disease. Many participants expressed intent to increase activities of advance care planning with this knowledge. This confirms high public interest in predictive testing for Alzheimer’s disease and suggests this may be an opportunity to engage patients in advance care planning discussions.

Reactions to learning a “not elevated” amyloid PET result in a preclinical Alzheimer’s disease trial

“…Learning that they have increased risk of developing AD dementia due to elevated amyloid may cause some individuals to set up advance healthcare directives and other medicolegal arrangements such as living wills [14]. Reduced motivation to complete such arrangements due to biomarker outcomes could have negative implications, especially for individuals who are at high risk for other causes of late-life disability, such as stroke or myocardial infarction, even if their risk for AD is relatively lower.…”

“…Disclosure of biomarker results in the clinical trial setting most frequently involves communication of negative results, such as not elevated brain amyloid and consequent ineligibility. Potential negative implications of this disclosure include misunderstanding and reduced motivation for optimal health behaviors [12–14]. The impact on willingness to participate in future trials is unknown.…”

<p>Alzheimer’s Disease – Why We Need Early Diagnosis</p>

“…A variety of studies suggest that most people would support targeted screening of those at risk of dementia and disclosure of dementia. [28][29][30][31][32] In a Canadian study of communityliving, older individuals without cognitive impairment, virtually all (98%) stated they would want to be informed of a diagnosis whether or not medication was available to treat it. 29 A questionnaire survey conducted among 2678 randomly selected adults across the US and four European countries, which asked whether subjects would undergo a hypothetical early medical test for Alzheimer's disease, found that potential demand was high with 67% reporting they would want to know if they were going to develop the disease.…”

Study partners should be required in preclinical Alzheimer’s disease trials

“…Patients will likely begin to consider financial matters such as the timing of retirement and where they will live. Issues of future healthcare decisions will be considered [ 44 ]. Such planning will be critical not only to maximize health, but also to minimize the risks associated with early signs of cognitive impairment such as medication errors, driving accidents [ 45 ], and financial error and abuse [ 46 ].…”