Clinical trials for developing new therapeutic and preventive treatments for Alzheimer's disease are often costly, complicated and sometimes not possible to carry out with old individuals with less mobility and significant medical issues. The study published in the journal Alzheimer's & Dementia showed the results of a novel four-year, randomized clinical trial evaluating different home-based methods to assess cognitive function and decline in participants over 75 years of age.
Almost 600 persons participated in the home-based assessment (HBA) study; all had been previously diagnosed as either possessing normal cognitive abilities or suffering from Mild Cognitive Impairment, a condition that often precedes AD.
The HBA study evaluated three different methods for monitoring and measuring cognitive function, particularly as participants progressed from normal abilities to impairment and dementia. There were three primary objectives: 1. Establish feasibility and efficiency of the three home-based assessment methods; 2. Determine how home-based assessments captured cognitive change over time; and 3. Evaluate participants' adherence in taking prescribed medication as a performance-based assessment of functional ability.
Researchers also wanted to determine if home-based assessments would improve participant retention rates, lower study costs and create a more robust representation of varied study participants.
The assessment methods used were mail-in questionnaires with live telephone interviews; automated telephone calls with an interactive voice-response system; and computer-based assessments with internet connectivity, using a kiosk interface installed at the participants homes. Cognitive and functional tests were employed using all three assessment methods.
Feasibility was measured by the ability to recruit, screen, enroll and retain participants. Efficiency was measured by the number of site staff contacts and amount of site staff time required to complete assessments.
The team found that all three approaches were feasible, but with modestly different degrees of success. Dropout rates were low and similar across technologies, though participants who had kiosk tools installed in their homes were more likely to dropout earlier.
Staff resources were also higher for the kiosk group. All of the in-home instruments were able to distinguish between neurologically stable participants and those experiencing cognitive decline. Internet-based assessments were less efficient compared to testing by live assessors.
Overall, researchers said the results were broadly encouraging, and worth further investigation and development.
"This study taught us how to engage a diverse community of very elderly subjects with a mean age over 80 years in web-based data collection, as well as in traditional testing methods over multiple years," Sano said.
By providing the tools and the access to all technologies, the study was also able to engage a large group of minority participants, demonstrating that participation is possible when resources are provided.
Howard Feldman, MD, director of ADCS and professor of neurosciences at UC San Diego School of Medicine, said the HBA study sets in motion multiple possibilities.
"We are always looking at ways to improve cognitive assessments by the most effective and expedient means possible. If we can make participating in clinical research easier on participants, through tools they are comfortable using, everyone benefits. This study is another reminder that human interaction is an important part of successful clinical trials."