Impact of COVID-19 on brain connectivity and rehabilitation outcome after stroke.

Background: Coronavirus disease (COVID-19) may induce neurological issues, impacting brain structure and stroke recovery. Limited studies have explored its effects on post-stroke rehabilitation. Our study compares brain structure and connectivity, assessing rehabilitation outcomes based on pre-stroke COVID-19 infection. Methods: A retrospective analysis of 299 post-stroke rehabilitation cases from May 2021 to January 2023 included two groups: those diagnosed with COVID-19 at least two weeks before stroke onset (COVID group) and those without (control group). Criteria involved first unilateral supratentorial stroke, <3 months post-onset, initial MR imaging, and pre- and post-rehabilitation clinical assessments. Propensity score matching ensured age, sex, and initial clinical assessment similarities. Using lesion mapping, tract-based statistical analysis, and group-independent component analysis MRI scans were assessed for structural and functional differences. Results: After propensity score matching, 12 patients were included in each group. Patient demographics showed no significant differences. Analyses of MR imaging revealed no significant differences between COVID and control groups. Post-rehabilitation clinical assessments improved notably in both groups, however the intergroup analysis showed no significant difference. Conclusions: Previous COVID-19 infection did not affect brain structure or connectivity nor outcomes after rehabilitation.

Validation of Claims-Based Frailty Index for Identifying Moderate-to-Severe Dementia in Medicare Beneficiaries.

OBJECTIVE: Previous research using the National Health and Aging Trends Study showed that a claims-based frailty index (CFI) could be useful for identifying moderate-to-severe dementia in Medicare claims data. This study aims to validate the findings in an independent cohort. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: The study included 658 fee-for-service beneficiaries with dementia who participated in the 2016-2020 Medicare Current Beneficiary Survey in the community-dwelling. METHODS: We operationalized the Functional Assessment Staging Test (FAST) scale (range: 1-7, stages 5-7 indicate moderate-to-severe dementia) using survey information. CFI (range: 0-1, higher scores indicate greater frailty) was calculated using Medicare claims 12 months before the participants' interview date. Using the previously proposed cut point of 0.280, we calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for identifying moderate-to-severe dementia. Survey procedures were used to account for survey design and weighted to reflect national estimates. RESULTS: The population had a mean age (SD) of 80.7 (8.9) years, 58.5% female, and 101 beneficiaries (14.8%) had moderate-to-severe dementia. The CFI cut point of 0.280 demonstrated sensitivity 0.49 (95% CI, 0.38-0.59), specificity 0.80 (0.77-0.84), PPV 0.30 (0.23-0.38), and NPV 0.90 (0.87-0.93). Compared with those with a CFI <0.280, beneficiaries with a CFI ≥0.280 had an elevated risk of mortality (2.9% vs 4.1%) over 1 year. CONCLUSIONS AND IMPLICATIONS: These results confirm our previous findings that CFI among beneficiaries with a dementia diagnosis is a useful measure of moderate-to-severe dementia for Medicare claims data.

Pre-procedural nursing home length of stay and outcomes of transcatheter aortic valve replacement.

BACKGROUND: Older adults with severe aortic stenosis (AS) may receive care in a nursing home (NH) prior to undergoing transcatheter aortic valve replacement (TAVR). NH level of care can be used to stabilize medical conditions, to provide rehabilitation services, or for long-term care services. Our primary objective is to determine whether NH utilization pre-TAVR can be used to stratify patients at risk for higher mortality and poor disposition outcomes at 30 and 365 days post-TAVR. METHODS: We conducted a retrospective cohort study among Medicare beneficiaries who spent ≥1 day in an NH 6 months before TAVR (2011-2019). The intensity of NH utilization was categorized as low users (1-30 days), medium users (31-89 days), long-stay NH residents (≥ 100 days, with no more than a 10-day gap in care), and high post-acute rehabilitation patients (≥90 days, with more than a 10-day gap in care). The probabilities of death and disposition were estimated using multinomial logistic regression, adjusting for age, sex, and race. RESULTS: Among 15,581 patients, 9908 (63.6%) were low users, 4312 (27.7%) were medium users, 663 (4.3%) were high post-acute care rehab users, and 698 (4.4%) were long-stay NH residents before TAVR. High post-acute care rehabilitation patients were more likely to have dementia, weight loss, falls, and extensive dependence of activities of daily living (ADLs) as compared with low NH users. Mortality was the greatest in high post-acute care rehab users: 5.5% at 30 days, and 36.4% at 365 days. In contrast, low NH users had similar mortality rates compared with long-stay NH residents: 4.8% versus 4.8% at 30 days, and 24.9% versus 27.0% at 365 days. CONCLUSION: Frequent bouts of post-acute rehabilitation before TAVR were associated with adverse outcomes, yet this metric may be helpful to determine which patients with severe AS could benefit from palliative and geriatric services.

Antiplatelet and Anticoagulant Use in Nursing Home Residents With Atrial Fibrillation.

This cross-sectional study evaluates the use of oral anticoagulants and antiplatelets, including aspirin, among nursing home residents with atrial fibrillation.

Efficacy of personalized repetitive transcranial magnetic stimulation based on functional reserve to enhance ambulatory function in patients with Parkinson's disease: study protocol for a randomized controlled trial.

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is one of the non-invasive brain stimulations that modulate cortical excitability through magnetic pulses. However, the effects of rTMS on Parkinson's disease (PD) have yielded mixed results, influenced by factors including various rTMS stimulation parameters as well as the clinical characteristics of patients with PD. There is no clear evidence regarding which patients should be applied with which parameters of rTMS. The study aims to investigate the efficacy and safety of personalized rTMS in patients with PD, focusing on individual functional reserves to improve ambulatory function. METHODS: This is a prospective, exploratory, multi-center, single-blind, parallel-group, randomized controlled trial. Sixty patients with PD will be recruited for this study. This study comprises two sub-studies, each structured as a two-arm trial. Participants are classified into sub-studies based on their functional reserves for ambulatory function, into either the motor or cognitive priority group. The Timed-Up and Go (TUG) test is employed under both single and cognitive dual-task conditions (serial 3 subtraction). The motor dual-task effect, using stride length, and the cognitive dual-task effect, using the correct response rate of subtraction, are calculated. In the motor priority group, high-frequency rTMS targets the primary motor cortex of the lower limb, whereas the cognitive priority group receives rTMS over the left dorsolateral prefrontal cortex. The active comparator for each sub-study is bilateral rTMS of the primary motor cortex of the upper limb. Over 4 weeks, the participants will undergo 10 rTMS sessions, with evaluations conducted pre-intervention, mid-intervention, immediately post-intervention, and at 2-month follow-up. The primary outcome is a change in TUG time between the pre- and immediate post-intervention evaluations. The secondary outcome variables are the TUG under cognitive dual-task conditions, Movement Disorder Society-Unified Parkinson's Disease Rating Scale Part III, New Freezing of Gait Questionnaire, Digit Span, trail-making test, transcranial magnetic stimulation-induced motor-evoked potentials, diffusion tensor imaging, and resting state functional magnetic resonance imaging. DISCUSSION: The study will reveal the effect of personalized rTMS based on functional reserve compared to the conventional rTMS approach in PD. Furthermore, the findings of this study may provide empirical evidence for an rTMS protocol tailored to individual functional reserves to enhance ambulatory function in patients with PD. TRIAL REGISTRATION: ClinicalTrials.gov NCT06350617. Registered on 5 April 2024.

Evolving role of the health system CIO: perspectives from 33 health systems.

OBJECTIVES: This study explores the evolving position of the health system chief information officer (CIO) by identifying new core roles for success. METHODS: An advisory board of industry executives and system leaders guided the study. Purposeful sampling was used to invite chief executive officer and CIOs from 65 not-for-profit US health systems to participate. Interviews were conducted with 51 executives from 33 different systems, using a comprehensive interview topic guide. Interview transcripts were analysed using NVivo software, focusing on themes related to the evolving role of the health system CIO. RESULTS: Analyses revealed three main themes, with the CIO as (1) enabler of strategic change and transformation, (2) strategic developer of technology and leadership talent and (3) driver of organisational culture. DISCUSSION: The role of CIO has undergone transformation from technology and information system management to strategic leadership within the broader health system context. It highlights the importance of comprehensive business knowledge for CIOs and the need for other C-suite executives to have a deeper understanding of information and technology. CONCLUSION: As healthcare continues to evolve, the role of the CIO is expected to expand further, requiring a blend of technical and strategic business skills. This evolution presents opportunities for health systems to enhance their leadership development programmes, preparing leaders for the complexities of the contemporary health system sector.

C1 Facetectomy and Ventral Fixation of Occipitoatlantoaxial Complex for Concurrent Congenital Atlanto-Occipital Dislocation and Atlantoaxial Instability in a Toy Poodle.

An 8-month-old, 3.4 kg, castrated male Toy Poodle was referred for progressive tetraparesis and respiratory disorder without a history of trauma. Repeated computed tomography (CT) and magnetic resonance imaging (MRI) with different positions of the neck revealed concurrent atlanto-occipital dislocation (AOD) and atlantoaxial instability (AAI) with spinal cord compression. This case was unique due to its congenital nature and the absence of trauma. The surgical treatment involved precise removal of the C1 vertebra's ventral articular facet, which was compressing on the spinal cord, attributed to its fixed and malaligned position within the atlantooccipital joint. Following facetectomy, the stabilization of the occipital bone to the C2 vertebra was achieved by screws, wire, and polymethyl methacrylate. Two days after surgery, the dog recovered ambulation and showed gradual improvement in gait, despite mild residual ataxia. Postoperative CT and radiographs showed successful decompression of the spinal cord. The screw loosening was confirmed at 114 days, which was managed successfully by extracting the affected screws. Through the 21-month monitoring period, the dog showed a normal gait with a wide-based stance of the pelvic limbs when standing and experienced no pain. This case represents the first report of concurrent congenital AOD and AAI treated with a ventral surgical approach, contributing new insights to the understanding and management of such complex cranio-cervical junction disorders in veterinary neurosurgery.

No Additional Effects of Sequential Facilitatory Cerebral and Cerebellar rTMS in Subacute Stroke Patients.

The aim of this study was to investigate the additional effects of cerebellar rTMS on the motor recovery of facilitatory rTMS over affected primary motor cortex (M1) in subacute stroke patients. Twenty-eight subacute stroke patients were recruited in this single-blind, randomized, controlled trial. The Cr-Cbll group received Cr-Cbll rTMS stimulation consisting of high-frequency rTMS over affected M1 (10 min), motor training (10 min), and high-frequency rTMS over contralesional Cbll (10 min). The Cr-sham group received sham rTMS instead of high-frequency rTMS over the cerebellum. Ten daily sessions were performed for 2 weeks. A Fugl-Meyer Assessment (FMA) was measured before (T0), immediately after (T1), and 2 months after the intervention (T2). A total of 20 participants (10 in the Cr-Cbll group and 10 in the Cr-sham group) completed the intervention. There was no significant difference in clinical characteristics between the two groups at T0. FMA was significantly improved after the intervention in both Cr-Cbll and Cr-sham groups (p < 0.05). However, there was no significant interaction in FMA between time and group. In conclusion, these results could not demonstrate that rTMS over the contralesional cerebellum has additional effects to facilitatory rTMS over the affected M1 for improving motor function in subacute stroke patients.

Postoperative use of sleep aids and delirium in older adults after major surgery: A retrospective cohort study.

BACKGROUND: Sleep aids are commonly prescribed to treat sleep disturbance, a modifiable risk factor for postoperative delirium in older patients. The use of melatonin receptor agonists in the postoperative period has been increasing. The comparative safety of melatonin receptor agonists, zolpidem, and temazepam remains uncertain. METHODS: This retrospective study included 22,083 patients ≥65 years old who initiated melatonin receptor agonists, zolpidem, or temazepam after major surgery in the Premier Healthcare Database 2009-2018. We performed propensity score-based overlap weighting and estimated the risk ratio (RR) and risk difference (RD) of postoperative delirium as the primary outcome and a composite of delirium or new antipsychotic initiation, pneumonia, and in-hospital mortality as secondary outcomes. RESULTS: The mean age of the study population was 78 (SD, 7) years and 50% were female. There was no significant difference in the risk of postoperative delirium among patients treated with melatonin receptor agonists (3.4%, reference group), zolpidem (2.9%; RR [95% CI], 0.9 [0.7-1.2]; RD [95% CI] per 100 persons, -0.3 [-1.1 to 0.6]), and temazepam (3.1%; 0.9 [0.7-1.1]; RD [95% CI] per 100 persons, -0.5 [-1.2 to 0.3]). The risks of delirium or new antipsychotic initiation, pneumonia, and in-hospital mortality were also similar among all groups. CONCLUSIONS: Melatonin receptor agonists were not associated with a lower risk of postoperative delirium and other adverse outcomes compared with zolpidem and temazepam in older adults after major surgery.

Assessing the Benefits and Harms of Pharmacotherapy in Older Adults with Frailty: Insights from Pharmacoepidemiologic Studies of Routine Health Care Data.

The objective of this review is to summarize and appraise the research methodology, emerging findings, and future directions in pharmacoepidemiologic studies assessing the benefits and harms of pharmacotherapies in older adults with different levels of frailty. Older adults living with frailty are at elevated risk for poor health outcomes and adverse effects from pharmacotherapy. However, current evidence is limited due to the under-enrollment of frail older adults and the lack of validated frailty assessments in clinical trials. Recent advancements in measuring frailty in administrative claims and electronic health records (database-derived frailty scores) have enabled researchers to identify patients with frailty and to evaluate the heterogeneity of treatment effects by patients' frailty levels using routine health care data. When selecting a database-derived frailty score, researchers must consider the type of data (e.g., different coding systems), the length of the predictor assessment period, the extent of validation against clinically validated frailty measures, and the possibility of surveillance bias arising from unequal access to care. We reviewed 13 pharmacoepidemiologic studies published on PubMed from 2013 to 2023 that evaluated the benefits and harms of cardiovascular medications, diabetes medications, anti-neoplastic agents, antipsychotic medications, and vaccines by frailty levels. These studies suggest that, while greater frailty is positively associated with adverse treatment outcomes, older adults with frailty can still benefit from pharmacotherapy. Therefore, we recommend routine frailty subgroup analyses in pharmacoepidemiologic studies. Despite data and design limitations, the findings from such studies may be informative to tailor pharmacotherapy for older adults across the frailty spectrum.

Frailty and Clinical Outcomes of Ticagrelor Versus Clopidogrel in Older Adults With Acute Myocardial Infarction.

BACKGROUND: Ticagrelor is recommended over clopidogrel in acute coronary syndrome based on the results of the PLATO (Study of Platelet Inhibition and Patient Outcomes) trial. We aimed to emulate PLATO in older adults with and without frailty and with acute coronary syndrome treated with percutaneous coronary intervention. METHODS AND RESULTS: We created a new-user cohort of Medicare fee-for-service beneficiaries aged ≥65 years hospitalized for acute coronary syndrome from 2014 to 2018 and initiated ticagrelor or clopidogrel following percutaneous coronary intervention. Frailty was defined using a validated claims-based frailty index ≥0.25. Coprimary outcomes were major adverse cardiovascular events and major bleeding. Follow-up began on the date of first outpatient prescription for ticagrelor or clopidogrel and ended on the earliest date for an outcome event, death, discontinuation of the index drug, or disenrollment from Medicare. The study included 42 843 older adults; 23% were frail. After propensity score matching, the rates of major adverse cardiovascular events per 100 person-years comparing ticagrelor versus clopidogrel groups were 7.8 and 7.3 in the frail cohort (hazard ratio [HR], 1.07 [95% CI, 0.84-1.36]) and 3.7 and 4.2 in the nonfrail cohort (HR, 0.87 [95% CI, 0.75-1.02]). The corresponding rates of major bleeding were 4.3 and 3.8 in the frail cohort (HR, 1.12 95% CI, [0.80-1.56]) and 2.2 and 1.8 in the nonfrail cohort (HR, 1.22 [95% CI, 0.98-1.51]). CONCLUSIONS: There was a trend toward a modest reduction in risk of major adverse cardiovascular events and a trend toward a modest increase in risk of major bleeding with ticagrelor compared with clopidogrel in the nonfrail cohort. There was insufficient evidence for the benefit of ticagrelor in frail older adults.

Crosswalk Algorithms for Cognitive and Functional Outcomes Among 2013-2018 Medicare Beneficiaries With Dementia.

OBJECTIVE: Before 2019, the Minimum Data Set (MDS) and Outcome and Assessment Information Set (OASIS) had incongruent response categories for rating cognitive impairment and activities of daily living (ADLs), hindering direct comparisons between nursing facilities and home health. We devised rule-based algorithms to compare cognitive impairment and ADL limitations between these 2 care settings among people with Alzheimer's disease and Alzheimer's disease-related dementias (ADRD). DESIGN: A retrospective cohort study. SETTING AND PARTICIPANTS: Included fee-for-service Medicare beneficiaries (2013-2018) transitioning from nursing facilities to home health, with 1-year of continuous enrollment, aged ≥65 years, diagnosed ADRD, and with complete MDS discharge and OASIS admission assessments (N = 398,496). METHODS: We identified target phenotypes using the Cognitive Function Scale (CFS) and ADL items from the MDS discharge assessment as reference standards. We compared 6 OASIS-based algorithms for cognitive impairment and 1 for each ADL limitation by estimating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: The average age was 83.5 (SD = 7.5) years and 82.3% transitioned from nursing to home health within 3 days. In the MDS discharge assessment, 42.2% had moderate-to-severe cognitive impairment. ADL limitations ranged from 71.4% for feeding to 97.8% for bathing. Compared with the moderate-to-severe cognitive impairment (CFS ≥3) on the MDS, the OASIS cognitive assessment indicating "considerable assistance to total dependence in routine situations" had 24% sensitivity, 94% specificity, 75% PPV, and 63% NPV. The ADL limitation algorithms exhibited high sensitivities (>96%) and PPVs (>94%) except for feeding (Sensitivity: 82%; PPV: 74%). Despite the short time frame between the 2 assessments, the OASIS admission assessment showed a higher prevalence of ADL limitations than the MDS discharge assessment. CONCLUSIONS AND IMPLICATIONS: We highlighted differences in patient function between post-acute care settings. Our algorithms can help researchers, clinicians, and policymakers standardize patient-centered outcomes for comparative effectiveness research or quality initiatives.

Longitudinal changes in a claims-based frailty proxy measure compared to concurrent changes in the Fried frailty phenotype.

BACKGROUND: Frailty is a dynamic aging-related syndrome, but measuring frailty transitions is challenging. The Faurot frailty index is a validated Medicare claims-based frailty proxy based on demographic and billing information. We evaluated whether three-year changes in the Faurot frailty index were consistent with concurrent changes in the frailty phenotype in a cohort of older adults. METHODS: We used longitudinal data from the National Health and Aging Trends (NHATS) study with Medicare claims linkage (2010-2018). We identified older adults (66+ years) in the 2011 and 2015 NHATS cohorts with at least one year of Medicare fee-for-service continuous enrollment (N=6,951). We described annual changes in mean claims-based frailty for up to three-years, based on concurrent transitions in the frailty phenotype. RESULTS: At baseline, 32% were robust, 48% prefrail, and 19% frail based on the frailty phenotype. Mean claims-based frailty for older adults who were robust at baseline and worsened to frail increased over three-years (0.09-0.25). Similarly, those who worsened from prefrail to frail experienced an increase in mean claims-based frailty (0.14-0.26). Improvements in the frailty phenotype did not correspond to decreases in claims-based frailty. Older adults whose frailty phenotype improved over time had a lower baseline claims-based frailty score than those who experienced stable or worsening frailty. CONCLUSIONS: Older adults who experienced a frailty phenotype worsening over three years experienced concurrent increases in the Faurot frailty index. Our results suggest that claims data may be used to identify clinically meaningful worsening in frailty.

Automated segmentation of MRI white matter hyperintensities in 8,421 patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: To date, only a few small studies have attempted deep learning-based automatic segmentation of white matter hyperintensity (WMH) lesions in patients with cerebral infarction, which is complicated because stroke-related lesions can obscure WMH borders. We developed and validated deep learning algorithms to segment WMH lesions accurately in patients with cerebral infarction, using multisite datasets involving 8,421 patients with acute ischemic stroke. MATERIALS AND METHODS: We included 8,421 stroke patients from 9 centers in Korea. 2D UNet and SE-Unet models were trained using 2,408 FLAIR MRI from 3 hospitals and validated using 6,013 FLAIR MRIs from 6 hospitals. WMH segmentation performance was assessed by calculating DSC, correlation coefficient, and concordance correlation coefficient compared to a human-segmented gold standard. In addition, we obtained an uncertainty index that represents overall ambiguity in the voxel classification for WMH segmentation in each patient based on the Kullback-Leibler divergence. RESULTS: In the training dataset, the mean age was 67.4±13.0 years and 60.4% were men. The mean (95% CI) DSCs for Unet in internal testing and external validation were respectively 0.659 (0.649-0.669) and 0.710 (0.707-0.714), which were slightly lower than the reliability between humans (DSC=0.744; 95% CI=0.738-0.751; P=.031). Compared with the Unet, the SE-Unet demonstrated better performance, achieving a mean DSC of 0.675 (0.666-0.685; P<.001) in the internal testing and 0.722 (0.719-0.726; P<.001) in the external validation; moreover, it achieved high DSC values (ranging from 0.672 to 0.744) across multiple validation datasets. We observed a significant correlation between WMH volumes that were segmented automatically and manually for the Unet (r=0.917, P<.0001) and even stronger for the SE-Unet (r=0.933, P<.0001). The SE-Unet also attained a high concordance correlation coefficient (ranging from 0.841 to 0.956) in external test datasets. In addition, the uncertainty indices in the majority of patients (86%) in the external datasets were below 0.35, with an average DSC of 0.744 in these patients. CONCLUSIONS: We developed and validated deep learning algorithms to segment WMH in patients with acute cerebral infarction using the largest-ever MRI datasets. In addition, we showed that the uncertainty index can be used to identify cases where automatic WMH segmentation is less accurate and requires human review. ABBREVIATIONS: WMH = white matter hyperintensity; CNN = convolutional neural networks; SE = squeeze-and-excitation; KL = Kullback-Leibler; ReLU = rectified linear unit; LKW = last known well; mRS = modified Rankin Scale; NIHSS = National Institute of Health Stroke Scale; LAA = large artery atherosclerosis; SVO = small vessel occlusion; CE = cardioembolism.

Leadership to Accelerate Healthcare's Digital Transformation: Evidence From 33 Health Systems.

GOAL: The COVID-19 pandemic, healthcare market disruptors, and new digital healthcare technologies have made a substantial impact on the delivery of healthcare services, highlighting the critical roles of leaders in hospitals and health systems. This study sought to understand the evolving roles of CEOs, CIOs, and other executive leaders in the postpandemic era and highlight the adaptability and strategic vision of executives in shaping the future of healthcare delivery. METHODS: Between October 2022 and May 2023, 51 interviews were conducted with CEOs, CIOs, and other executives responsible for delivering technology solutions for 33 nonprofit health systems in the United States. They were asked to describe their backgrounds; how information solutions and technologies were viewed within their organizations' strategy, operations, and governance; and the key characteristics of executive leaders. PRINCIPAL FINDINGS: The study has found that effective CEOs have an authentic belief in technology's role in achieving their organization's mission and that contemporary CIOs are strategic executive partners who align strategy with culture to improve care. This study examines how healthcare systems are creating digitally savvy executive leadership teams that operate in a new, integrated model that unites previously siloed functions. PRACTICAL APPLICATIONS: Some healthcare CIOs are unprepared for current and future business challenges, and some CEOs are unsure how to leverage digital technologies and C-suite expertise to transform their organizations. This research provides insights into how the nation's health systems are building and sustaining leadership teams capable of adapting to the healthcare environment and accelerating organizational transformation.

Use of chronic care management service among Medicare beneficiaries in 2015-2019.

BACKGROUND: The Centers for Medicare and Medicaid Services (CMS) introduced chronic care management (CCM) services in 2015 for patients with multiple chronic diseases. Few studies examine the utilization of CCM services by geographic region, sociodemographic, and clinical characteristics. METHODS: We used 2014-2019 Medicare claims data from a 5% random sample of fee-for-service beneficiaries aged 65 years or over. We included beneficiaries potentially eligible for CCM services because they had multiple chronic conditions (1,073,729 in 2015 and 1,130,523 in 2019). We calculated the proportion of potentially eligible beneficiaries receiving CCM service each year for the total population and by geographic region, sociodemographic, and clinical characteristics. RESULTS: The proportion of beneficiaries with two or more chronic conditions receiving CCM services increased from 1.1% in 2015 to 3.4% in 2019. The increase in CCM use was higher in the southern region, among dually eligible beneficiaries and beneficiaries with a greater burden of chronic conditions (2-5 conditions vs ≥10 conditions: 0.7% vs 2.0% in 2015; 2.1% vs 7.0% in 2019) and frailty (robust vs severely frail: 0.6% vs 3.3% in 2015; 1.9% vs 9.4% in 2019). Nearly one out of five recipients did not continue CCM service after the initial service. CONCLUSION: We found that CCM service is being used by a very small fraction of eligible patients. Barriers and facilitators to more effective CCM adoption should be identified and incorporated into strategies that encourage more widespread use of this Medicare benefit.