Comparison of existing methods for algorithmic classification of dementia in the Health and Retirement Study

Background: Dementia ascertainment is difficult and costly, hindering the use of large, representative studies such as the Health and Retirement Study (HRS) to monitor trends or disparities in dementia. To address this issue, multiple groups of researchers have developed algorithms to classify dementia status in HRS participants using data from HRS and the Aging, Demographics, and Memory Study (ADAMS), an HRS sub-study that systematically ascertained dementia status. However, the relative performance of each algorithm has not been systematically evaluated. Objective: To compare the performance of five existing algorithms, overall and by sociodemographic subgroups. Methods: We created two standardized datasets: (a) training data (N=786, i.e. ADAMS Wave A and corresponding HRS data, which was used previously to create the algorithms) and (b) validation data (N=530, i.e. ADAMS Waves B, C, and D and corresponding HRS data which was not used previously to create the algorithms). In both, we used each algorithm to classify HRS participants as demented or not demented and compared the algorithmic diagnoses to the ADAMS diagnoses. Results: In the training data, overall classification accuracies ranged from 80% to 87%, sensitivity ranged from 53% to 90%, and specificity ranged from 79% to 96% across the five algorithms. Though overall classification accuracy was similar in the validation data (range: 79% to 88%), sensitivity was much lower (range: 17% to 61%), while specificity was higher (range: 82% to 98%) compared to the training data. Classification accuracy was generally worse in non-Hispanic blacks (range: 68% to 85%) and Hispanics (range: 65% to 88%), compared to non-Hispanic whites (range: 79% to 88%). Across datasets, sensitivity was generally higher for proxy-respondents, while specificity (and overall accuracy) was higher for self-respondents. Conclusions: Worse sensitivity in the validation dataset may suggest either overfitting or that the algorithms are better at identifying prevalent versus incident dementia, while differences in performance across algorithms suggest that the usefulness of each will vary depending on the user’s purpose. Further planned work will evaluate algorithm performance in external validation datasets

Implications of the Use of Algorithmic Diagnoses or Medicare Claims to Ascertain Dementia.

INTRODUCTION: Formal dementia ascertainment with research criteria is resource-intensive, prompting growing use of alternative approaches. Our objective was to illustrate the potential bias and implications for study conclusions introduced through use of alternate dementia ascertainment approaches. METHODS: We compared dementia prevalence and risk factor associations obtained using criterion-standard dementia diagnoses to those obtained using algorithmic or Medicare-based dementia ascertainment in participants of the baseline visit of the Aging, Demographics, and Memory Study (ADAMS), a Health and Retirement Study (HRS) sub-study. RESULTS: Estimates of dementia prevalence derived using algorithmic or Medicare-based ascertainment differ substantially from those obtained using criterion-standard ascertainment. Use of algorithmic or Medicare-based dementia ascertainment can, but does not always lead to risk-factor associations that substantially differ from those obtained using criterion-standard ascertainment. DISCUSSION/CONCLUSIONS: Absolute estimates of dementia prevalence should rely on samples with formal dementia ascertainment. Use of multiple algorithms is recommended for risk-factor studies when formal dementia ascertainment is not available

Medicare Hospice Policy Changes and Beneficiaries\u27 Rate of Live Discharge and Length-of-Stay

CONTEXT: The 2014 Improving Medicare Post-Acute Care Transformation (IMPACT) Act systemized audits of long hospice stays, and the 2016 two-tier payment system decreased daily reimbursement rates after 60 days of enrollment. Both aimed to reduce long stays. OBJECTIVES: Examine how live discharge rates and length of stay changed in relation to the policies. METHODS: We computed monthly hospice-level percent live discharges and length of stay using 2008-2019 Medicare hospice claims. We compared prepolicies trends and postpolicies trends overall, within Alzheimer\u27s disease and related dementias (ADRD) patients, within lung cancer patients, and stratified by hospice ownership (for-profit vs. nonprofit/government-owned). RESULTS: We included 10,539,912 and 10,453,025 episodes of care in the analytical samples for live discharge and length of stay analyses, respectively. Overall percent live discharges declined during the prepolicies period (-0.13 percentage-points per month, 95% CI: -0.14, -0.12), but exhibited no significant change during the postpolicies period. Trends were driven primarily by for-profits, with similar patterns within ADRD and lung cancer patients. Overall, mean length of stay increased over time, with greater rate of increase during the postpolicies period (0.41 days per month, 95% CI: 0.39, 0.42) compared to the prepolicies period (0.12 days per month, 95% CI: 0.10, 0.14). Length-of-stay increased faster among ADRD patients, but changed minimally for lung cancer patients. CONCLUSION: Live discharge rates declined significantly during the prepolicies period, but plateaued after implementation of the policies, driven by changes in for-profits. However, the policies did not reduce length of stay, which increased at faster rates, suggesting that postpolicies excess live discharges were not restricted to long-stay patients

Racial disparities and temporal trends in dementia misdiagnosis risk in the United States.

© 2019 The Authors Introduction: Systematic disparities in misdiagnosis of dementia across racial/ethnic groups have implications for health disparities. We compared the risk of dementia under- and overdiagnosis in clinical settings across racial/ethnic groups from 2000 to 2010. Methods: We linked fee-for-service Medicare claims to participants aged ≥70 from the nationally representative Health and Retirement Study. We classified dementia status using an algorithm with similar sensitivity and specificity across racial/ethnic groups and assigned clinical dementia diagnosis status using ICD-9-CM codes from Medicare claims. Multinomial logit models were used to estimate relative risks of clinical under- and overdiagnosis between groups and over time. Results: Non-Hispanic blacks had roughly double the risk of underdiagnosis as non-Hispanic whites. While primary analyses suggested a shrinking disparity over time, this was not robust to sensitivity analyses or adjustment for covariates. Risk of overdiagnosis increased over time in both groups. Discussion: Our results suggest that efforts to reduce racial disparities in underdiagnosis are warranted

Self-Reported Hearing Loss and Nonfatal Fall-Related Injury in a Nationally Representative Sample.

© 2019 The American Geriatrics Society BACKGROUND/OBJECTIVE: To evaluate the relationship between self-reported hearing loss and nonfatal fall-related injury in a nationally representative sample of community-dwelling adults living in the United States. DESIGN: Cross-sectional analysis of national survey data. SETTING: National Health Interview Survey (2016). PARTICIPANTS: A total of 30 994 community-dwelling adults in the United States, aged 18 years and older. MEASUREMENTS: We evaluated the association between self-reported hearing loss and nonfatal injury resulting from a fall in the previous 3 months. We used multivariate logistic regression to calculate adjusted odds ratios (ORs) and evaluated effect measure modification by age. RESULTS: The odds of nonfatal fall-related injury were 1.60 times higher among respondents with hearing loss compared to respondents without hearing loss (95% confidence interval [CI] = 1.20-2.12; P =.0012). Results were unchanged when adjusting for demographics (OR = 1.59; 95% CI = 1.18-2.15; P =.002). After adjustment for cardiovascular risk factors, cardiovascular disease, visual impairment, and limitation caused by nervous system/sensory organ conditions and depression, anxiety, or another emotional problem, the OR fell to 1.27 (95% CI = 0.92-1.74; P =.14). In the fully adjusted model, including adjustment for vestibular vertigo, there was little support to link hearing loss and fall-related injury (OR = 1.16; 95% CI = 0.84-1.60; P =.36). Effect modification by age was not observed. CONCLUSIONS: Self-reported hearing loss may be a clinically useful indicator of increased fall risk, but treatment for hearing loss is unlikely to mitigate this risk, given that there is no independent association between self-reported hearing loss and nonfatal falls after accounting for vestibular function and other potential confounders

The association between midlife lipid levels and late-life brain amyloid deposition.

Elevated low-density lipoprotein cholesterol and total cholesterol in midlife and decline in total cholesterol from mid- to late-life are associated with incident dementia. Whether brain amyloid deposition mediates this relationship is unclear. We explored the association between midlife blood lipid levels and mid- to late-life change in lipid levels with brain amyloid deposition assessed using florbetapir PET scans in a biracial sample of 325 nondemented participants of the Atherosclerosis Risk in Communities–PET Amyloid Imaging study. Midlife total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides were not significantly associated with late-life amyloid burden after adjusting for covariates. Associations between changes in lipids and late-life amyloid deposition were similarly null. Lipids may contribute to dementia risk through alternate mechanisms