Why Are Spousal Caregivers More Prevalent Than Nonspousal Caregivers As Study Partners in AD Dementia Clinical Trials?

Objectives: Most Alzheimer disease (AD) caregivers are not spouses and yet most AD dementia trials enroll spousal study partners. This study examines the association between caregiver relationship to the patient and willingness to enroll in an AD clinical trial and how caregiver burden and research attitudes modify willingness.

Design: Interviews with 103 AD caregivers who met criteria for ability to serve as a study partner.

Results: A total of 54% of caregivers were spouses or domestic partners and the remaining were adult children. Willingness to enroll a patient in a clinical trial was associated with being a spouse [odds ratio (OR)=2.53, P=0.01], increasing age (OR=1.39, P=0.01), and increasing scores on the Research Attitudes Questionnaire (OR=1.39, P<0.001). No measures of caregiver burden or patient health were significant predictors of willingness. In multivariate models both research attitudes (OR=1.37, P<0.001) and being a spouse, as opposed to an adult child, (OR=2.06, P=0.048) were independently associated with willingness to participate.

Conclusions: Spousal caregivers had both a higher willingness to participate and a more positive attitude toward research. Caregiver burden had no association with willingness to participate. The strongest predictor of willingness was research attitudes.