Specialist Availability and Drug Adherence in Older Adults with Dementia Across Regions of the United States.

BACKGROUND: Access to specialists facilitates appropriate Alzheimer's disease and related dementia (ADRD) medication use and adherence. However, there is little information on the impact of specialists' availability on ADRD medication adherence, especially in regions of the United States (US) where specialists are scarce, e.g., the Deep South (DS). OBJECTIVE: To ascertain whether the availability of specialty physicians in the DS and other US regions predicts ADRD medication adherence among community-dwelling older adultsMethods:We conducted secondary analyses of claims data for 54,194 Medicare beneficiaries with ADRD in 2013-2015. Medication adherence was measured using the proportion of days covered (PDC). Multivariable-adjusted Modified Poisson regression was used to examine associations of adherence with physicians' availability by region. RESULTS: The race/ethnicity distribution was 81.44% white, 9.17% black, 6.24% Hispanic, 2.25% Asian, and 1% other; 71.81% were female, and 42.36% were older than 85 years. Beneficiaries across regions differed in all individual and contextual characteristics except sex and comorbidities. Neurologists and psychiatrists' availability was not significantly associated with adherence (DS = 1.00, 0.97-1.03 & non-DS = 1.01, 1.00-1.01). Race and having ≥1 specialist visits were associated with a lower risk of adherence in both regions (p < 0.0001). Advanced age, dual Medicare/Medicaid eligibility, and living in non-large metropolitan areas, were associated with adherence in the non-DS region. CONCLUSION: Among older Americans with ADRD, a context defined by specialist availability does not affect adherence, but other context characteristics related to socioeconomic status may. Research should further examine the influence of individual and contextual factors on ADRD treatment among older adults.

Dementia Care in Diverse Older Adults in the U.S. Deep South and the Rest of the United States.

BACKGROUND: Use of specialists and recommended drugs has beneficial effects for older adults living with Alzheimer's disease and related dementia (ADRD). Gaps in care may exist for minorities, e.g., Blacks, and especially in the United States (U.S.) Deep South (DS), a poor U.S. region with rising ADRD cases and minority overrepresentation. Currently, we have little understanding of ADRD care utilization in diverse populations in this region and elsewhere in the U.S. (non-DS), and the factors that adversely impact it. OBJECTIVE: To examine utilization of specialists and ADRD drugs (outcomes) in racial/ethnic groups of older adults with ADRD and the personal or context-level factors affecting these outcomes in DS and non-DS. METHODS: We obtained outcomes and personal-level covariates from claims for 127,512 Medicare beneficiaries with ADRD in 2013-2015, and combined county-level data in exploratory factor analysis to define context-level covariates. Adjusted analyses tested significant association of outcomes with Black/White race and other factors in DS and non-DS. RESULTS: Across racial/ethnic groups, 33%-43% in DS and 43%-50% in non-DS used specialists; 47%-55% in DS and 41%-48% in non-DS used ADRD drugs. In adjusted analyses, differences between Blacks and Whites were not significant. Vascular dementia, comorbidities, poverty, and context-level factor "Availability of Medical Resources" were associated with specialist use; Alzheimer's disease and senile dementia, comorbidities, and specialist use were associated with drug use. In non-DS only, other individual, context-level covariates were associated with the outcomes. CONCLUSION: We did not observe significant gaps in ADRD care in DS and non-DS; however, research should further examine determinants of low specialist and drug use in these regions.

Cognitive Processing Speed Is Strongly Related to Driving Skills, Financial Abilities, and Other Instrumental Activities of Daily Living in Persons With Mild Cognitive Impairment and Mild Dementia.

BACKGROUND: Cognitive processing speed is important for performing everyday activities in persons with mild cognitive impairment (MCI). However, its role in daily function has not been examined while simultaneously accounting for contributions of Alzheimer's disease (AD) risk biomarkers. We examine the relationships of processing speed and genetic and neuroimaging biomarkers to composites of daily function, mobility, and driving. METHOD: We used baseline data from 103 participants on the MCI/mild dementia spectrum from the Applying Programs to Preserve Skills trial. Linear regression models examined relationships of processing speed, structural magnetic resonance imaging (MRI), and genetic risk alleles for AD to composites of performance-based instrumental activities of daily living (IADLs), community mobility, and on-road driving evaluations. RESULTS: In multivariable models, processing speed and the brain MRI neurodegeneration biomarker Spatial Pattern of Abnormality for Recognition of Early Alzheimer's disease (SPARE-AD) were significantly associated with functional and mobility composite performance. Better processing speed and younger age were associated with on-road driving ratings. Genetic risk markers, left hippocampal atrophy, and white matter lesion volumes were not significant correlates of these abilities. Processing speed had a strong positive association with IADL function (p < .001), mobility (p < .001), and driving (p = .002). CONCLUSIONS: Cognitive processing speed is strongly and consistently associated with critical daily functions in persons with MCI in models including genetic and neuroimaging biomarkers of AD risk. SPARE-AD scores also significantly correlate with IADL performance and mobility. Results highlight the central role of processing speed in everyday task performance among persons with MCI/mild dementia.