Many of us are unfortunately too familiar with Alzheimer’s disease, an irreversible brain disease caused by damage to the brain’s nerve cells which slowly destroys memory, language, and cognitive function [1]. Alzheimer’s dementia (AD) is a progressive process through which an individual goes from being forgetful to losing the ability to communicate or carry out the simplest daily task as a result of Alzheimer’s disease. This article focuses on the evidence through published medical literature that there are consistent and adverse disparities among black people compared to white people with respect to the incidence and prevalence of AD, the use of anti-dementia medications, and participation in clinical trials. These disparities negatively impact the quality of care black people with AD receive when compared to their white counterparts. This is a public health inequality and injustice that requires us to better coordinate a response to address and eliminate these disparities.
The most often cited estimate in the literature is that black people are twice as likely as white people to develop AD [1]. A 1999 study established that in the 65 and older population, black people are twice as likely as white people to have AD [2]. A 2017 study to analyze the incidence rate of AD in the 90 and older population similarly found that black people have the highest incidence rate with a 28% higher risk of AD than white people [3]. Consistent with the incidence rates, a meta-analysis of population-based studies revealed that black people had the highest prevalence, or proportion of people with AD. [4]. Given these studies, there is little room for debate that AD disproportionately impacts black people.
The causes of the increased incidence and prevalence of AD in black people have not been clearly established. The literature has identified medical and non-medical conditions which can contribute to the increased risk of AD in black people. For example, some studies proposed that vascular conditions, such as cardiovascular disease and diabetes, or obesity, may contribute to the increased risk as black people have a higher burden of these conditions [5]. Genetic risk factors for AD in black people have also been identified [6]. One large genetic study called the Alzheimer Disease Dementia Consortium revealed that the genes APOE-E4 and ABCA7 increased the risk of AD in black people, strengthening the idea that genetics may play a role in AD onset [7]. Interestingly, the findings so far suggest that both these genes are definitive risk factors for black people, whereas only APOE-E4 confers a similar degree of risk in white people [8].
At the same time, there is growing evidence that socioeconomic factors are potential reasons for the increased risk. In a very recent study, Zuelsdorff et al. observed that stressful life experiences such as in education, finances, or legal system, were linked to poor late life cognitive function and that black people experienced over 60% more stressful life events than white people [9]. Also, another study by Kind et al. discovered that individuals living in disadvantaged neighborhoods which pose barriers to nutritious food, exercise, or toxin free environment, had disproportionately higher levels of an Alzheimer’s disease biomarker in their spinal fluid suggesting that socioeconomic factors may play a role in AD risk [10]. These studies should not at all be surprising as these social determinants of health are well known in the public health realm as sources of disease burden and negative outcome.
In light of the undisputable increased incidence of AD in black people, it is shocking to learn that black people are less likely to be prescribed or use certain anti-dementia medications on the market, such as Aricept and Namenda, which can reduce AD symptoms and increase function. One medical study investigated the use of anti-dementia medications between white people and minorities in a national community sample [11]. This study revealed that minorities, including black people, had a 30% lower use of such medications [11]. One researcher attributed the low medication usage to the underdiagnosis or delay in diagnosis of black people with AD as black people are more likely to delay seeking treatment because of physical, social, or economic barriers to healthcare [12].
We are in a situation where simply increasing the prescription of anti-dementia medications in black people with AD is not a solution. One roadblock to this concept as a solution is that there is such low black participation in clinical trials that these trials cannot ensure that new drugs or treatments are safe or effective for black people because they are not adequately studied. Several studies have consistently found that black people are significantly underrepresented in most clinical trials for new drugs and therapies for AD [13, 14]. As low black participation in clinical research limits medical knowledge as to how AD may present in black people or the potential effect of treatment in black people, simply prescribing more drugs to an unstudied population does not promote racial equity.
The Alzheimer’s Association conducted a study which involved surveying adults and caregivers to assess their interest in clinical trials. It was found that black people were less interested in participating in clinical trials for AD than any other surveyed race [15]. The reasons more frequently cited by black people than white people against participation in clinical trials included a lack of trust in medical research and fear of unfair treatment [16]. This should hardly be surprising if we think back on the historical trend of unfair treatment of black people in the medical system, such as the infamous Tuskegee study where hundreds of black men with curable syphilis were deliberately left untreated resulting in their illness and death. The CDC later deemed this study “ethically unjustified” [16], but the chilling effects of the study linger to this day as many black people still fear and are reluctant to participate in clinical research.
Furthermore, a recent study conducted by Raman et al. demonstrated that black people were more likely than white people to be excluded from AD trials due to not meeting cognitive inclusion criteria [14]. The cognitive inclusion criteria involved achieving certain scores on standardized cognitive tests, such as the Mini Mental Status Exam, and black people were disproportionately excluded based on their scores. This strongly suggests a racial bias in screening processes further exacerbating low black participation and preventing diversity in clinical research. For example, Brian Van Buren, a 69 year old black man, applied to five AD clinical trials when he was diagnosed with mild cognitive deficits and he was rejected from all five trials due to underlying health conditions that affect many black people [17]. Quita Highsmith, chief diversity officer of Genentech biotechnology company artfully captured the problem with racial bias or lack of diversity in clinical trials for AD: “We are at a critical crossroad….Lots of data is being collected at clinical trials that will be used to develop treatments so it’s important to make sure the data reflects all populations affected….We don’t want communities left behind” [17].
The published research sheds light that racial discrimination continues to invade the realm of healthcare. One significant point is that many research studies discussed above are fairly recent which means that any efforts to eradicate healthcare disparities for black people have not yet been effective and further efforts are required. Based on the surveys conducted by the Alzheimer’s Association and the work of other researchers, the themes found to discourage black people from seeking medical care or participating in clinical research included experiences of unequal treatment and racism due to historical events and contemporary experiences as well as lack of cultural competency. As the surveys reveal that racial discrimination or insensitivity lies at the root of the problem, we need to shift our focus to establishing cultural competence in both the healthcare industry and clinical trials.
Cultural competence is the ability to understand and respect the beliefs, values and histories of individuals of all cultural backgrounds [18]. For medical professionals, cultural competence has recently come to the forefront as an important component of providing the best care to patients. Dr. Luz Maria Garcini, assistant professor at Rice University whose research focuses on the health needs of marginalized communities, explained: “Cultural competence improves interpersonal interactions, helps to build trust, conveys respect, reduces biases that may lead to inaccurate diagnoses and treatments, and increases the chances that patients may be more compliant with the medical recommendations given” [18]. Most medical schools are now incorporating an element of cultural competence training as part of the medical school curriculum which means there is a hope for a future of medical professionals with a base understanding of cultural competence.
One may argue that one downside of cultural competence training is that it does not address the core societal injustices - socioeconomic conditions and racism - which predispose black people to a higher incidence of certain diseases in the first place, as discussed above. Cultural competence training for healthcare professionals may run the risk of improperly classifying racial disparities as a problem with healthcare professionals, instead of the broader societal problem that it is. This may be a valid observation, but if there is an opportunity to reduce racial disparities in healthcare, should we just throw in the towel because it does not fully eliminate racial disparities from society’s structure?
In an article published in the Journal of General Internal Medicine, Dr. Malat expressed another potential downside that cultural competence training, by focusing on cultural traits and beliefs, actually reinforces stereotypes about racial and ethnic minorities and suggests that racial groups are fixed and have homogenous cultures. This breeds the problem of generalizations about black people’s “culture,” all the while the dominant medical ideology is supposed to be objective and without culture [19]. The response to this is that cultural competence training serves merely as a guideline, and that healthcare providers still have the ability to inquire about each patient’s unique social beliefs and behaviors.
Cultural competence training may not be a standalone solution to the racial disparities that exist within our society. However, it presents an accessible method to address structural injustices in the healthcare layer and should not be abandoned merely because it does not fix the whole problem. There are present day obstacles to efficient cross-cultural communication in the healthcare setting. These can be best addressed by incorporating cultural competence elements, which include eliminating racial bias from research screening and engaging culturally diverse staff, language interpreters, and education on cultures to increase black participation in clinical trials, to seek physician contact, and to adhere to medication recommendations. Educating the medical community to understand other cultural points of view or historical experiences will work to establish trust and will result in black people receiving better quality of care with respect to AD and other medical conditions.
References
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