Racial/Ethnic Disparities in Misidentification of Dementia in Medicare Claims: Results from the Washington Heights-Inwood Columbia Aging Project

Article type: Research Article

Authors: Zhu, Carolyn W.^{a; b; *} | Gu, Yian^{c; d; e; f} | Cosentino, Stephanie^{c; d; e} | Kociolek, Anton J.^e | Hernandez, Michelle^e | Stern, Yaakov^{c; d; e}

Affiliations: [a] Brookdale Department of Geriatrics and Palliative Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA | [b] James J Peters VA Medical Center, Bronx, NY, USA | [c] Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA | [d] Gertrude H. Sergievsky Center, Columbia University Irving Medical Center, New York, NY, USA | [e] Taub Institute for Research in Alzheimer’s Disease and the Aging, Columbia University Irving Medical Center, New York, NY, USA | [f] Department of Epidemiology, Columbia University Mailman School of Public Health, New York, NY, USA

Correspondence: [*] Correspondence to: Carolyn W. Zhu, PhD, Brookdale Department of Geriatrics & Palliative Medicine, Icahn School of Medicine at Mount Sinai and James J Peters VA Medical Center, 130 West Kingsbridge Road, Bronx NY 10468, USA. Tel.: +1 718 584 9000/Ext. 1372; Fax: +1 718 741 4211; E-mail: carolyn.zhu@mssm.edu.

Abstract: Background:Misidentification of dementia in Medicare claims is quite common. Objective:We examined potential race/ethnic disparities in misidentification of dementia in Medicare claims in a diverse cohort of older adults who underwent careful clinical assessment. Methods:Participants were enrolled in the Washington Heights-Inwood Columbia Aging Project (WHICAP), a multiethnic, population-based, prospective study of cognitive aging in which dementia status was assessed using a rigorous clinical protocol. ICD-9-CM and ICD-10-CM diagnosis codes in all available Medicare claims (1999–2019) were compared to clinical dementia diagnosis and categorized into three mutually exclusive groups: 1) congruent-, 2) over-, and 3) under- identification during the study period. Multinomial logistic regression model was used to examine the relationship between race (White, African American/Black, other) and ethnicity (Hispanic/Latinx, non-Hispanic/Latinx) and congruency of dementia identification after controlling for clinical (cognition, function, comorbidities) and demographic characteristics (age, sex, education), and inpatient and outpatient utilization. Results:Across all person-years, 88.4% had congruent identification of dementia compared to clinical diagnosis, in 4.1% of the times participants were over-identified with dementia, and 7.5% of the times the participants were under-identified. Rates of misidentification was higher in minority participants than in White, non-Hispanic participants. Multivariable estimation results showed that the probability of over-identification with dementia was 2.2% higher for African American/Black than White (p = 0.05) and 2.7% higher for Hispanic participants than non-Hispanics (p = 0.03) participants. Differences in under-identification by race/ethnicity were not statistically significant. Conclusions:African American/Black and Hispanic participants were more likely over-identified with dementia in Medicare claims.

Keywords: Alzheimer’s disease, clinical diagnosis, disparities, Medicare claims

DOI: 10.3233/JAD-230584

Journal: Journal of Alzheimer's Disease, vol. 96, no. 1, pp. 359-368, 2023