Association between results of an amyloid PET scan and healthcare utilization in individuals with cognitive impairment.

BACKGROUND: The Imaging Dementia Evidence for Amyloid Scanning (IDEAS) study reports that amyloid PET scans help providers diagnose and manage Alzheimer's disease and related dementias (ADRD). Using CARE-IDEAS, an IDEAS supplemental study, we examined the association between amyloid PET scan result (elevated or non-elevated amyloid), patient characteristics, and participant healthcare utilization. METHODS: We linked respondents in CARE-IDEAS study to their Medicare fee-for-service records (n = 1333). We examined participants' cognitive impairment-related, outpatient, emergency department (ED), and inpatient encounters in the year before compared with the 2 years after the amyloid PET scan. RESULTS: Individuals with a non-elevated amyloid scan had more healthcare encounters throughout the overall study period than those with an elevated amyloid scan. Regardless of the amyloid scan result, cognitive impairment-related and outpatient encounters overall decreased, but ED and inpatient encounters increased in the 2 years after the scan compared with the year prior. There was minimal evidence of differences in healthcare utilization between participants with an elevated and non-elevated amyloid scan. CONCLUSIONS: There is no difference in change in healthcare utilization between people with scans showing elevated and non-elevated beta-amyloid.

The Benefits of Nursing Home Air Purification on COVID-19 Outcomes: A Natural Experiment.

OBJECTIVES: Improving indoor air quality is one potential strategy to reduce the transmission of SARS-CoV-2 in any setting, including nursing homes, where staff and residents have been disproportionately and negatively affected by the COVID-19 pandemic. DESIGN: Single group interrupted time series. SETTING AND PARTICIPANTS: A total of 81 nursing homes in a multifacility corporation in Florida, Georgia, North Carolina, and South Carolina that installed ultraviolet air purification in their existing heating, ventilation, and air conditioning systems between July 27, 2020,k and September 10, 2020. METHODS: We linked data on the date ultraviolet air purification systems were installed with the Nursing Home COVID-19 Public Health File (weekly data reported by nursing homes on the number of residents with COVID-19 and COVID-19 deaths), public data on data on nursing home characteristics, county-level COVID-19 cases/deaths, and outside air temperature. We used an interrupted time series design and ordinary least squares regression to compare trends in weekly COVID-19 cases and deaths before and after installation of ultraviolet air purification systems. We controlled for county-level COVID-19 cases, death, and heat index. RESULTS: Compared with pre-installation, weekly COVID-19 cases per 1000 residents (-1.69; 95% CI, -4.32 to 0.95) and the weekly probability of reporting any COVID-19 case (-0.02; 95% CI, -0.04 to 0.00) declined in the post-installation period. We did not find any difference pre- and post-installation in COVID-19-related mortality (0.00; 95% CI, -0.01 to 0.02). CONCLUSIONS AND IMPLICATIONS: Our findings from this small number of nursing homes in the southern United States demonstrate the potential benefits of air purification in nursing homes on COVID-19 outcomes. Intervening on air quality may have a wide impact without placing significant burden on individuals to modify their behavior. We recommend a stronger, experimental design to estimate the causal effect of installing air purification devices on improving COVID-19 outcomes in nursing homes.

Prevalence and incidence of depressive symptoms and diagnosis of depression as associated with elevated amyloid among Medicare beneficiaries with cognitive impairment.

BACKGROUND: Depression and cognitive impairment commonly co-occur, and it has been hypothesized that the two share pathological processes. Our objective for this study was to determine the relationship between elevated ß-amyloid level and the prevalence and incidence of depressive symptoms and diagnosed depression over two years among fee-for-service Medicare beneficiaries with cognitive impairment. METHODS: We utilized data from the CARE-IDEAS cohort study (N = 2078) including two measures of depressive symptoms (PHQ-2) and administrative claims data to identify pre-scan and incident depression diagnosis in subsample of fee-for-service Medicare beneficiaries (N = 1443). We used descriptive statistics and Poisson regression models with robust covariance. RESULTS: Beneficiaries whose scan results indicated not-elevated ß-amyloid were significantly more likely to have been diagnosed with depression pre-scan (46.4 % vs. 33.1 %). There was no significant association between elevated amyloid and the incidence of depressive symptoms or diagnosed depression. LIMITATIONS: The sample was limited to Medicare beneficiaries with cognitive impairment. Race/ethnic composition and education levels were not representative of the general population and there was substantial loss to follow-up. Mixed depressive / anxious episodes were captured as diagnoses of depression, potentially overestimating depression in this population. CONCLUSIONS: There was a high prevalence and incidence of diagnosed depression in this cohort of Medicare beneficiaries, but the incidence of depressive symptoms and diagnosed depression was not associated with elevated ß-amyloid.

Cost effectiveness of non-drug interventions that reduce nursing home admissions for people living with dementia.

INTRODUCTION: Six million Americans live with Alzheimer's disease and Alzheimer's disease and related dementias (AD/ADRD), a major health-care cost driver. We evaluated the cost effectiveness of non-pharmacologic interventions that reduce nursing home admissions for people living with AD/ADRD. METHODS: We used a person-level microsimulation to model the hazard ratios (HR) on nursing home admission for four evidence-based interventions compared to usual care: Maximizing Independence at Home (MIND), NYU Caregiver (NYU); Alzheimer's and Dementia Care (ADC); and Adult Day Service Plus (ADS Plus). We evaluated societal costs, quality-adjusted life years and incremental cost-effectiveness ratios. RESULTS: All four interventions cost less and are more effective (i.e., cost savings) than usual care from a societal perspective. Results did not materially change in 1-way, 2-way, structural, and probabilistic sensitivity analyses. CONCLUSION: Dementia-care interventions that reduce nursing home admissions save societal costs compared to usual care. Policies should incentivize providers and health systems to implement non-pharmacologic interventions.

The Effects of Increasing State Minimum Wage on Family and Paid Caregiving.

Older adults may receive either or a combination of unpaid family/friend and paid caregiving. The consumption of family/friend and paid caregiving may be sensitive to minimum wage policies. We used data (n = 11,698 unique respondents) from the Health and Retirement Study and a difference-in-differences design to evaluate associations between increases in state minimum wage between 2010 and 2014 and family/friend and paid caregiving consumed by adults age 65+ years. We also examined responses to increases in minimum wage for respondents with dementia or Medicaid beneficiaries. People living in states that increased their minimum wage did not consume substantially different hours of family/friend, paid, or any family/friend or paid caregiving. We did not observe differential responses between increases in minimum wage and hours of family/friend or paid caregiving among people with dementia or Medicaid beneficiaries. Increases in state minimum wage were not associated with changes in caregiving consumed by adults age 65+.

Cost-effectiveness models for Alzheimer's disease and related dementias: IPECAD modeling workshop cross-comparison challenge.

INTRODUCTION: The credibility of model-based economic evaluations of Alzheimer's disease (AD) interventions is central to appropriate decision-making in a policy context. We report on the International PharmacoEconomic Collaboration on Alzheimer's Disease (IPECAD) Modeling Workshop Challenge. METHODS: Two common benchmark scenarios, for the hypothetical treatment of AD mild cognitive impairment (MCI) and mild dementia, were developed jointly by 29 participants. Model outcomes were summarized, and cross-comparisons were discussed during a structured workshop. RESULTS: A broad concordance was established among participants. Mean 10-year restricted survival and time in MCI in the control group ranged across 10 MCI models from 6.7 to 9.5 years and 3.4 to 5.6 years, respectively; and across 4 mild dementia models from 5.4 to 7.9 years (survival) and 1.5 to 4.2 years (mild dementia). DISCUSSION: The model comparison increased our understanding of methods, data used, and disease progression. We established a collaboration framework to assess cost-effectiveness outcomes, an important step toward transparent and credible AD models.

Association Between the Patient Driven Payment Model and Therapy Utilization and Patient Outcomes in US Skilled Nursing Facilities.

Importance: In October 2019, Medicare changed its skilled nursing facility (SNF) reimbursement model to the Patient Driven Payment Model (PDPM), which has modified financial incentives for SNFs that may relate to therapy use and health outcomes. Objective: To assess whether implementation of the PDPM was associated with changes in therapy utilization or health outcomes. Design Setting and Participants: This cross-sectional study used a regression discontinuity (RD) approach among Medicare fee-for-service postacute-care patients admitted to a Medicare-certified SNF following hip fracture between January 2018 and March 2020. Exposures: Skilled nursing facility admission after PDPM implementation. Main Outcomes and Measures: Main outcomes were individual and nonindividual (concurrent and group) therapy minutes per day, hospitalization within 40 days of SNF admission, SNF length of stay longer than 40 days, and discharge activities of daily living score. Results: The study cohort included 201 084 postacute-care patients (mean [SD] age, 83.8 [8.3] years; 143 830 women [71.5%]; 185 854 White patients [92.4%]); 147 711 were admitted pre-PDPM, and 53 373 were admitted post-PDPM. A decrease in individual therapy (RD estimate: -15.9 minutes per day; 95% CI, -16.9 to -14.6) and an increase in nonindividual therapy (RD estimate: 3.6 minutes per day; 95% CI, 3.4 to 3.8) were observed. Total therapy use in the first week following admission was about 12 minutes per day (95% CI, -13.3 to -11.3) (approximately 13%) lower for residents admitted post-PDPM vs pre-PDPM. No consistent and statistically significant discontinuity in hospital readmission (0.31 percentage point increase; 95% CI, -1.46 to 2.09), SNF length of stay (2.7 percentage point decrease in likelihood of staying longer than 40 days; 95% CI, -4.83 to -0.54), or functional score at discharge (0.04 point increase in activities of daily living score; 95% CI, -0.19 to 0.26) was observed. Nonindividual therapy minutes were reduced to nearly zero in late March 2020, likely owing to COVID-19-related restrictions on communal activities in SNFs. Conclusions and Relevance: In this cross-sectional study of SNF admission after PDPM implementation, a reduction of total therapy minutes was observed following the implementation of PDPM, even though PDPM was designed to be budget neutral. No significant changes in postacute outcomes were observed. Further study is needed to understand whether the PDPM is associated with successful discharge outcomes.

Microsimulation Model Calibration with Approximate Bayesian Computation in R: A Tutorial.

Mathematical health policy models, including microsimulation models (MSMs), are widely used to simulate complex processes and predict outcomes consistent with available data. Calibration is a method to estimate parameter values such that model predictions are similar to observed outcomes of interest. Bayesian calibration methods are popular among the available calibration techniques, given their strong theoretical basis and flexibility to incorporate prior beliefs and draw values from the posterior distribution of model parameters and hence the ability to characterize and evaluate parameter uncertainty in the model outcomes. Approximate Bayesian computation (ABC) is an approach to calibrate complex models in which the likelihood is intractable, focusing on measuring the difference between the simulated model predictions and outcomes of interest in observed data. Although ABC methods are increasingly being used, there is limited practical guidance in the medical decision-making literature on approaches to implement ABC to calibrate MSMs. In this tutorial, we describe the Bayesian calibration framework, introduce the ABC approach, and provide step-by-step guidance for implementing an ABC algorithm to calibrate MSMs, using 2 case examples based on a microsimulation model for dementia. We also provide the R code for applying these methods.