Asian, Hispanic, and Black people were diagnosed at a later stage of dementia than white people, an analysis of California Medicare claims data showed.
Asian older adults also were less likely to receive a comprehensive diagnostic evaluation for dementia than others, reported Katherine Possin, PhD, of University of California San Francisco, and co-authors, in .
"We need to address these disparities urgently," Possin said. "These gaps in care can lead to missed reversible causes, generic treatment, and delayed planning," she told . "Furthermore, with disease-modifying therapies on the horizon that will require an etiological diagnosis, these disparities will deepen."
The analysis assessed claims for 10,472 California Medicare fee-for-service beneficiaries who were enrolled continuously from 2013 through 2015 and who received a diagnosis of either incident mild cognitive impairment (MCI) or dementia in the first 6 months of 2015. Mean age of beneficiaries was about 83 and 62% were women. Overall, 9.5% of the group identified as Asian, 3.9% as Black, 12.0% as Hispanic, and 74.6% as white.
Possin's group defined timeliness of diagnosis as a dichotomous variable based on whether incident MCI was diagnosed before dementia. Diagnostic workups were comprehensive if they included a specialist evaluation, laboratory assays (specifically, vitamin B12 and thyrotropin studies), and neuroimaging 6 months before or after the incident diagnosis date.
Overall, 21.2% of beneficiaries received a diagnosis of incident MCI (vs dementia), 34.6% received a specialist evaluation, 16.2% had lab testing, and 28.7% had neuroimaging studies.
Older adults who were Asian (OR 0.46 95% CI 0.38-0.56), Black (OR 0.73, 95% CI 0.56-0.94), or Hispanic (OR 0.62, 95% CI 0.52-0.72) were less likely to receive a diagnosis of MCI versus dementia than those who were white. Asian beneficiaries had a lower likelihood of receiving a comprehensive diagnostic workup than white beneficiaries (incident rate ratio 0.81, 95% CI 0.74-0.87). Associations remained significant after adjusting for age, sex, comorbidity burden, neighborhood disadvantage, and rurality.
Older age, residence in a highly disadvantaged neighborhood, and greater comorbidity burden each were independently associated with later diagnosis. Black beneficiaries who lived in disadvantaged neighborhoods were less likely to receive an MCI diagnosis; Hispanic beneficiaries in disadvantaged neighborhoods were less likely to receive a comprehensive workup.
One limitation of Medicare claims research is that it can't identify what's behind disparities, noted Claudia Kawas, MD, of University of California Irvine, and co-authors, in an accompanying editorial.
"For example, timeliness of diagnosis, as defined in this study, may possibly reflect clinician and health care system biases or poor performance of screening instruments in these populations, but it is also likely to be related to cultural differences in what is normal aging or the appropriate time to present to the healthcare system with memory problems," they wrote.
"A major challenge to our understanding of dementia care is the absence of diversity in study populations engaged in research," the editorialists observed. "Most of what we know today about risk and protective factors for dementia, treatment effects, and biomarkers related to cognitive impairment is derived from highly educated, urban dwelling, non-Hispanic white individuals. Recruiting diverse populations into research requires directed resources to cultivate trust and engage with different communities."
Clinicians can work to address disparities, Possin pointed out. "We recommend that primary care providers routinely ask all older patients about changes in memory and thinking skills, just as they would routinely check for other health factors like high blood pressure or hearing loss," she said. "When there is a concern, the next step is to conduct a standardized cognitive assessment and evaluate for reversible causes."
Dementia specialists also can help address gaps by reaching out to underserved communities, Possin added. "This can be done by strengthening referral pipelines and by providing education on brain health, including why timely diagnosis is important. Specialist providers need to take an active role to reduce inequities in access to their services."
The analysis was limited to Medicare fee-for-service beneficiaries in California and findings may not apply to other groups. The study also used a restricted lookback window to establish incident diagnoses of MCI and dementia.
Disclosures
This study was supported by the Centers for Medicare & Medicaid Services, the National Institute of Neurological Disorders and Stroke, the National Institute on Aging, and the Global Brain Health Institute.
Study authors reported relationships with NIH, American Academy of Neurology, Marinus Pharmaceuticals, Knowledge to Practice, Avid Radiopharmaceuticals, Eli Lilly, GE Healthcare, Life Molecular Imaging, Eisai, Johnson & Johnson, Axon Neurosciences, Eisai, Roche, Genentech, Merck, Rainwater Charitable Foundation, Alzheimer's Association, Cambridge National Institute for Health Research Biomedical Research Centre, American Brain Foundation, John Douglas French Alzheimer's Foundation, Safely You, Tau Consortium, Bluefield Project for Frontotemporal Dementia Research, Stanford Alzheimer's Disease Research Center, Buck Institute, Larry L. Hillblom Foundation, University of Texas Center for Brain Health, University of Washington Alzheimer's Disease Research Center, Harvard University Alzheimer's Disease Research Center, Guilford Press, Cambridge University Press, Johns Hopkins Press, Oxford University Press, Neurocase, Frontiers in Neurology, U.S. Department of Veterans Affairs, Commonwealth Foundation, Global Brain Health Institute, Quest Diagnostics, Administration for Community Living, Merck Foundation, ClearView Health Partners, and Vanguard. One researcher is associate editor of JAMA Neurology, but was not involved in any decisions regarding review of the manuscript or its acceptance.
The editorialists were supported by NIH.
Primary Source
JAMA Neurology
Tsoy E, et al "Assessment of racial/ethnic disparities in timeliness and comprehensiveness of dementia diagnosis in California" JAMA Neurol 2021; DOI: 10.1001/jamaneurol.2021.0399.
Secondary Source
JAMA Neurology
Kawas C, et al "Diversity and Disparities in Dementia Diagnosis and Care: A Challenge for All of Us" JAMA Neurol 2021; DOI: 10.1001/jamaneurol.2021.0285.