Including Persons with Alzheimer Disease in Research on Comorbid Conditions
Wall, Anji, IRB: Ethics & Human Research
Alzheimer disease is a progressive neurodegenerative condition that affects 4.5 million people in the United States, with the number expected to rise dramatically over the next fifty years due to the aging of the population. (1) The prevalence of Alzheimer disease is 5% in people aged 65-75, and almost 50% in people aged 85 and above. Alzheimer disease is characterized by the insidious, gradual progression of memory impairment, which leads to a decline in an individual's cognition and ability to perform activities of daily living, changes in personality and behavior, and increased health care costs. (2) There is no cure, and only a few treatments slow its progression. (3) The cost for caring for people with Alzheimer disease is estimated to be $60 billion annually in the United States alone. (4)
Considering the disease's prevalence and the absence of effective treatment options, it is not surprising that much research focuses on this condition. While the importance of Alzheimer disease research is recognized, there is much debate about whether Alzheimer patients should be permitted to participate in clinical trials and under what conditions. Discussions have focused on the appropriate risk-benefit ratio of Alzheimer disease trials and the types of consent (subject, proxy, or advance directive) that are acceptable. (5) The debates over the ethical conduct of Alzheimer disease research centers on determining the appropriate balance between protecting a vulnerable population from the potential risks of research while allowing subjects to participate in trials that could lead to individual medical benefit, as well as medical benefit for the population as a whole.
Discussions in the literature about research on persons with Alzheimer disease have been almost exclusively concerned with studies of treatments for the disease itself. (6) Although this is an important starting point, more attention should be given to the inclusion of persons with Alzheimer disease in research on comorbid medical conditions. It has been shown that the treatment of comorbid medical conditions such as cardiovascular disease, infection, pulmonary disease, renal insufficiency, arthritis, and diminution of vision and hearing can improve functionality and cognition in persons with Alzheimer disease. (7) Further, characteristics of medications for the disease or even the disease itself may alter the safety or efficacy of treatments for comorbid conditions. Thus, if Alzheimer patients are underrepresented in or excluded from research on comorbid conditions, optimal and safe treatments for these conditions in this population will remain unknown. If individuals are excluded from research trials on comorbid conditions by virtue of their cognitive vulnerability, they will be protected from the risks of research, but they will also be denied the potential benefits of research participation, both individually and as a group.
This article begins with a discussion of current guidelines regarding Alzheimer disease research so as to lay a foundation for extending these guidelines to more explicitly include research on comorbid medical conditions. The article then justifies including persons with Alzheimer disease in research on comorbid medical conditions, using data from several empirical studies that show treatment of these conditions is not only beneficial to the overall health of the individual, but also may be beneficial in decreasing the symptoms of the disease. Finally, the article uses the framework of social justice as understood in the research ethics literature to examine the inclusion of historically excluded groups in research and to support the conclusion that social justice requires persons with Alzheimer disease to be included in research on comorbid medical conditions unless a robust justification for exclusion is provided.
Comorbid Medical Conditions
Because Alzheimer disease most frequently affects elderly persons, it is not surprising to find that individuals with the disease commonly suffer from comorbid medical conditions. …