Publications

BACKGROUND: Federal programs measuring hospital quality of care for acute cardiovascular conditions are based solely on Medicare fee-for-service (FFS) beneficiaries, and exclude Medicare Advantage (MA) beneficiaries. In this study we characterize the proportion of Medicare beneficiaries enrolled in MA at the time of acute myocardial infarction (AMI), heart failure (HF), and ischemic stroke hospitalization.

METHODS: Retrospective cross-sectional study of short-term acute care hospitals using Medicare claims in 2009 and 2019.

RESULTS: There were 2,653 hospitals in 2009 and 2,732 hospitals in 2019. Across hospitals, the proportion of Medicare beneficiaries hospitalized for AMI who were enrolled in MA increased between 2009 (hospital-level median 14.4% [IQR 5.1%-26.0%]) and 2019 (33.3% [IQR 20.6%-45.2%]), with substantial variation across hospitals. Similar patterns were observed for HF (13.0% [IQR 5.3%-24.3%] to 31.0% [IQR 20.2%-42.3%]) and ischemic stroke (14.6% [IQR 5.3%-26.7%] to 33.3% [IQR 20.9%-46.0%]). Within each hospital referral region, hospital size (large 36.3% vs small 24.5%; adjusted difference 6.7%, 95% CI, 4.5%-8.8%), teaching status (teaching 34.5% vs nonteaching 28.2%; 2.8%, 1.4%-4.1%), and ownership status (private nonprofit 32.3% vs public 24.5%; 5.2%, 3.5%-6.9%) were each associated with a higher hospital MA proportion.

CONCLUSIONS: The proportion of Medicare beneficiaries hospitalized for AMI, HF, and ischemic stroke enrolled in MA doubled between 2009 and 2019, with substantial variation across hospitals. These findings have implications for federal efforts to measure and improve quality, which currently focus only on FFS beneficiaries.

Background Frailty is rarely assessed in clinical trials of patients who receive dual antiplatelet therapy (DAPT) after percutaneous coronary intervention. This study investigated whether frailty defined using claims data is associated with outcomes following percutaneous coronary intervention, and if there is a differential association in patients receiving standard versus extended duration DAPT. Methods and Results Patients ≥65 years of age in the DAPT (Dual Antiplatelet Therapy) Study, a randomized trial comparing 30 versus 12 months of DAPT following percutaneous coronary intervention, had data linked to Medicare claims (n=1326), and a previously validated claims-based index was used to define frailty. Net adverse clinical events, a composite of all-cause mortality, myocardial infarction, stroke, and major bleeding, were compared between frail and nonfrail patients. Patients defined as frail using claims data (12.0% of the cohort) had higher incidence of net adverse clinical events (23.1%) compared with nonfrail patients (10.7%; P<0.001) at 18-month follow-up and increased risk after multivariable adjustment (adjusted hazard ratio [HR], 2.24 [95% CI, 1.38-3.63]). There were no differences in effects of extended duration DAPT on net adverse clinical events for frail (HR, 1.42 [95% CI, 0.73-2.75]) and nonfrail patients (HR, 1.18 [95% CI, 0.83-1.68]; interaction P=0.61), although analyses were underpowered. Bleeding was highest among frail patients who received extended duration DAPT. Conclusions Among older patients in the DAPT Study, claims-defined frailty was associated with higher net adverse clinical events. Effects of extended duration DAPT were not different for frail patients, although comparisons were underpowered. Further investigation of how frailty influences ischemic and bleeding risks with DAPT are warranted. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00977938.

The rich longitudinal individual level data available from electronic health records (EHRs) can be used to examine treatment effect heterogeneity. However, estimating treatment effects using EHR data poses several challenges, including time-varying confounding, repeated and temporally non-aligned measurements of covariates, treatment assignments and outcomes, and loss-to-follow-up due to dropout. Here, we develop the subgroup discovery for longitudinal data algorithm, a tree-based algorithm for discovering subgroups with heterogeneous treatment effects using longitudinal data by combining the generalized interaction tree algorithm, a general data-driven method for subgroup discovery, with longitudinal targeted maximum likelihood estimation. We apply the algorithm to EHR data to discover subgroups of people living with human immunodeficiency virus who are at higher risk of weight gain when receiving dolutegravir (DTG)-containing antiretroviral therapies (ARTs) versus when receiving non-DTG-containing ARTs.

AIMS: Prior trials have demonstrated that intravascular imaging (IVI)-guided percutaneous coronary intervention (PCI) results in less frequent target lesion revascularization and major adverse cardiovascular events (MACEs) compared with standard angiographic guidance. The uptake and associated outcomes of IVI-guided PCI in contemporary clinical practice in the USA remain unclear. Accordingly, temporal trends and comparative outcomes of IVI-guided PCI relative to PCI with angiographic guidance alone were examined in a broad, unselected population of Medicare beneficiaries.

METHODS AND RESULTS: Retrospective cohort study of Medicare beneficiary data from 1 January 2013, through 31 December 2019 to evaluate temporal trends and comparative outcomes of IVI-guided PCI as compared with PCI with angiography guidance alone in both the inpatient and outpatient settings. The primary outcomes were 1 year mortality and MACE, defined as the composite of death, myocardial infarction (MI), repeat PCI, or coronary artery bypass graft surgery. Secondary outcomes were MI or repeat PCI at 1 year. Multivariable Cox regression was used to estimate the adjusted association between IVI guidance and outcomes. Falsification endpoints (hospitalized pneumonia and hip fracture) were used to assess for potential unmeasured confounding. The study population included 1 189 470 patients undergoing PCI (38.0% female, 89.8% White, 65.1% with MI). Overall, IVI was used in 10.5% of the PCIs, increasing from 9.5% in 2013% to 15.4% in 2019. Operator IVI use was variable, with the median operator use of IVI 3.92% (interquartile range 0.36%-12.82%). IVI use during PCI was associated with lower adjusted rates of 1 year mortality [adjusted hazard ratio (aHR) 0.96, 95% confidence interval (CI) 0.94-0.98], MI (aHR 0.97, 95% CI 0.95-0.99), repeat PCI (aHR 0.74, 95% CI 0.73-0.75), and MACE (aHR 0.85, 95% CI 0.84-0.86). There was no association with the falsification endpoint of hospitalized pneumonia (aHR 1.02, 95% CI 0.99-1.04) or hip fracture (aHR 1.02, 95% CI 0.94-1.10).

CONCLUSION: Among Medicare beneficiaries undergoing PCI, use of IVI has increased over the previous decade but remains relatively infrequent. IVI-guided PCI was associated with lower risk-adjusted mortality, acute MI, repeat PCI, and MACE.

BACKGROUND: Multiple interventions, including catheter-directed therapy (CDT), systemic thrombolysis (ST), surgical embolectomy (SE), and therapeutic anticoagulation (AC) have been used to treat intermediate to high-risk pulmonary embolism (PE), but the most effective and safest treatment remains unclear. Our study aimed to investigate the efficacy and safety outcomes of each intervention.

METHODS: We queried PubMed and EMBASE in January 2023 and performed a network meta-analysis of observational studies and randomized controlled trials (RCT), including high or intermediate-risk PE patients, and comparing AC, CDT, SE, and ST. The primary outcomes were in-hospital mortality and major bleeding. The secondary outcomes included long-term mortality (≥6 months), recurrent PE, minor bleeding, and intracranial hemorrhage.

RESULTS: We identified 11 RCTs and 42 observational studies involving 157,454 patients. CDT was associated with lower in-hospital mortality than ST (odds ratio [OR] [95% confidence interval (CI)]: 0.41 [0.31-0.55]), AC (OR [95% CI]: 0.33 [0.20-0.53]), and SE (OR [95% CI]: 0.61 [0.39-0.96]). Recurrent PE in CDT was lower than ST (OR [95% CI]: 0.66 [0.50-0.87]), AC (OR [95% CI]: 0.36 [0.20-0.66]), and trended lower than SE (OR [95% CI]: 0.71 [0.40-1.26]). Notably, ST had higher major bleeding risks than CDT (OR [95% CI]: 1.51 [1.19-1.91]) and AC (OR [95% CI]: 2.21 [1.53-3.19]). By rankogram analysis, CDT presented the highest p-score in in-hospital mortality, long-term mortality, and recurrent PE.

CONCLUSION: In this network meta-analysis of observational studies and RCTs involving patients with intermediate to high-risk PE, CDT was associated with improved mortality outcomes compared to other therapies, without significant additional bleeding risk.

BACKGROUND/AIMS: When the randomized clusters in a cluster randomized trial are selected based on characteristics that influence treatment effectiveness, results from the trial may not be directly applicable to the target population. We used data from two large nursing home-based pragmatic cluster randomized trials to compare nursing home and resident characteristics in randomized facilities to eligible non-randomized and ineligible facilities.

METHODS: We linked data from the high-dose influenza vaccine trial and the Music & Memory Pragmatic TRIal for Nursing Home Residents with ALzheimer's Disease (METRICaL) to nursing home assessments and Medicare fee-for-service claims. The target population for the high-dose trial comprised Medicare-certified nursing homes; the target population for the METRICaL trial comprised nursing homes in one of four US-based nursing home chains. We used standardized mean differences to compare facility and individual characteristics across the three groups and logistic regression to model the probability of nursing home trial participation.

RESULTS: In the high-dose trial, 4476 (29%) of the 15,502 nursing homes in the target population were eligible for the trial, of which 818 (18%) were randomized. Of the 1,361,122 residents, 91,179 (6.7%) were residents of randomized facilities, 463,703 (34.0%) of eligible non-randomized facilities, and 806,205 (59.3%) of ineligible facilities. In the METRICaL trial, 160 (59%) of the 270 nursing homes in the target population were eligible for the trial, of which 80 (50%) were randomized. Of the 20,262 residents, 973 (34.4%) were residents of randomized facilities, 7431 (36.7%) of eligible non-randomized facilities, and 5858 (28.9%) of ineligible facilities. In the high-dose trial, randomized facilities differed from eligible non-randomized and ineligible facilities by the number of beds (132.5 vs 145.9 and 91.9, respectively), for-profit status (91.8% vs 66.8% and 68.8%), belonging to a nursing home chain (85.8% vs 49.9% and 54.7%), and presence of a special care unit (19.8% vs 25.9% and 14.4%). In the METRICaL trial randomized facilities differed from eligible non-randomized and ineligible facilities by the number of beds (103.7 vs 110.5 and 67.0), resource-poor status (4.6% vs 10.0% and 18.8%), and presence of a special care unit (26.3% vs 33.8% and 10.9%). In both trials, the characteristics of residents in randomized facilities were similar across the three groups.

CONCLUSION: In both trials, facility-level characteristics of randomized nursing homes differed considerably from those of eligible non-randomized and ineligible facilities, while there was little difference in resident-level characteristics across the three groups. Investigators should assess the characteristics of clusters that participate in cluster randomized trials, not just the individuals within the clusters, when examining the applicability of trial results beyond participating clusters.