Long-term multimorbidity trajectories in older adults: The role of cancer, demographics, and health behaviors.

BACKGROUND: Multimorbidity is associated with premature mortality and excess health care costs. The burden of multimorbidity is highest among patients with cancer, yet trends and determinants of multimorbidity over time are poorly understood. METHODS: Via Medicare claims linked to Cancer Prevention Study II data, group-based trajectory modeling was used to compare National Cancer Institute comorbidity index score trends for cancer survivors and older adults without a cancer history. Among cancer survivors, multinomial logistic regression analyses evaluated associations between demographics, health behaviors, and comorbidity trajectories. RESULTS: In 82,754 participants (mean age, 71.6 years [SD, 5.1 years]; 56.9% female), cancer survivors (n = 11,265) were more likely than older adults without a cancer history to experience the riskiest comorbidity trajectories: (1) steady, high comorbidity scores (remain high; odds ratio [OR], 1.36; 95% CI, 1.29-1.45), and (2) high scores that increased over time (start high and increase; OR, 1.51; 95% CI, 1.38-1.65). Cancer survivors who were physically active postdiagnosis were less likely to fall into these two trajectories (OR, 0.73; 95% CI, 0.64-0.84, remain high; OR, 0.42; 95% CI, 0.33-0.53, start high and increase) compared to inactive survivors. Cancer survivors with obesity were more likely to have a trajectory that started high and increased (OR, 2.83; 95% CI, 2.32-3.45 vs. normal weight), although being physically active offset some obesity-related risk. Cancer survivors who smoked postdiagnosis were also six times more likely to have trajectories that started high and increased (OR, 6.86; 95% CI, 4.41-10.66 vs. never smokers). CONCLUSIONS: Older cancer survivors are more likely to have multiple comorbidities accumulated at a faster pace than older adults without a history of cancer. Weight management, physical activity, and smoking avoidance postdiagnosis may attenuate that trend.

Patients with dementia or frailty undergoing major limb amputation have poor outcomes.

OBJECTIVE: Major lower limb amputation is a disfiguring operation associated with impaired mobility and high near-term mortality. Informed decision-making regarding amputation requires outcomes data. Despite the co-occurrence of both chronic limb-threatening ischemia (CLTI) and Alzheimer's disease and related dementias (ADRD), there is sparse data on the outcomes of major limb amputation in this population and the impact of frailty. We sought to determine mortality, complications, readmissions, revisions, intensive interventions (eg, cardiopulmonary resuscitation), and other outcomes after amputation for CLTI in patients living with ADRD looking at the modifying effects of frailty. METHODS: We examined Medicare fee-for-service claims data from January 1, 2016, to December 31, 2020. Patients with CLTI undergoing amputation at or proximal to the ankle were included. Along with demographic information, dementia status, and comorbid conditions, we measured frailty using a claims-based frailty index. We dichotomized dementia and frailty (pre-frail/robust = "non-frail" vs moderate/severe frailty = "frail") to create four groups: non-frail/non-ADRD, frail/non-ADRD, non-frail/ADRD, and frail/ADRD. We used linear and logistic regression via generalized estimating equations in addition to performing selected outcomes analyses with death as a competing risk to understand the association between dementia status, frailty status, and 1-year mortality as our primary outcome in addition to the postoperative outcomes outlined above. RESULTS: Among 46,930 patients undergoing major limb amputation, 11,465 (24.4%) had ADRD and 24,790 (52.8%) had frailty. Overall, 55.9% of amputations were below-knee. Selected outcomes among frail/ADRD patients undergoing amputation (n = 10,153) were: 55.3% 1-year mortality 29.6% readmissions at 30 days, and 32.3% amputation revision/reoperation within 1 year. Of all four groups, those in the frail/ADRD had the worst outcomes only for 1-year mortality. CONCLUSIONS: First, patients with ADRD or moderate/severe frailty suffer an array of very poor outcomes after major limb amputation for CLTI, including high mortality, readmissions, revision, and risks of discharge to higher levels of care. Second, there is a complex relationship between outcome severity and ADRD/frailty status. Specifically, frailty is more often than ADRD associated with the poorest results for any given outcome. These data provide important outcomes data to help align decision-making with health care values and goals.

Percutaneous image-guided lumbar decompression and interspinous spacers for the treatment of lumbar spinal stenosis: A 2-year Medicare Claims Benchmark Study.

OBJECTIVE: This prospective longitudinal study compares outcomes between Medicare beneficiaries receiving percutaneous image-guided lumbar decompression (PILD) using the mild® procedure and a control group of patients receiving interspinous spacers for the treatment of lumbar spinal stenosis (LSS) with neurogenic claudication (NC). METHODS: Patients diagnosed with LSS with NC and treated with either the mild procedure or a spacer were identified in the Medicare claims database. The incidence of harms, the rate of subsequent interventions, and the overall combined rate of harms and subsequent interventions during 2-year follow-up after the index procedure were compared between the two groups and assessed for statistical significance with p = 0.05. RESULTS: The study included 2229 patients in the mild group and 3401 patients who were implanted with interspinous spacers. The rate of harms for those treated with the mild procedure was less than half that of patients implanted with a spacer (5.6% vs. 12.1%, respectively; p < 0.0001) during 2-year follow-up. The rate of subsequent interventions was not significantly different between the two groups (24.9% and 26.1% for the mild and spacer groups, respectively; p = 0.7679). The total rate of harms and subsequent interventions for mild was found to be noninferior to spacers (p < 0.0001). CONCLUSIONS: This comprehensive study of real-world Medicare claims data demonstrated a significantly lower rate of harms for the mild procedure compared to interspinous spacers for patients diagnosed with LSS with NC, and a similar rate of subsequent interventions during 2-year follow-up.

Evaluation of Medicare Claims for the Development of Heart Failure Diagnostics.

BACKGROUND: Although claims data provide a large and efficient source of clinical events, validation is needed prior to use in heart failure (HF) diagnostic development. METHODS AND RESULTS: Data from the Multisensor Chronic Evaluations in Ambulatory Heart Failure Patients (MultiSENSE) study, used to create the HeartLogic HF diagnostic, were linked with fee-for-service (FFS) Medicare claims. Events were matched by patient ID and date, and agreement was calculated between claims primary HF diagnosis codes and study event adjudication. HF events (HFEs) were defined as inpatient visits, or outpatient visits with intravenous decongestive therapy. Diagnostic performance was measured as HFE-detection sensitivity and false-positive rate (FPR). Linkage of 791 MultiSENSE subjects returned 320 FFS patients with an average follow-up duration of 0.94 years. Although study and claims deaths matched exactly (n = 14), matching was imperfect between study hospitalizations and acute inpatient claims events. Of 239 total events, 165 study hospitalizations (69%) matched inpatient claims events, 28 hospitalizations matched outpatient claims events (12%), 14 hospitalizations were study-unique (6%), and 32 inpatient events were claims-unique (13%). Inpatient HF classification had substantial agreement with study adjudication (κ = 0.823). Diagnostic performance was not different between claims and study events (sensitivity = 75.6% vs 77.6% and FPR = 1.539 vs 1.528 alerts/patient-year). HeartLogic-detected events contributed to > 90% of the HFE costs used for evaluation. CONCLUSIONS: Acceptable event matching, good agreement of claims diagnostic codes with adjudication, and equivalent diagnostic performance support the validity of using claims for HF diagnostic development.

Validity of Diagnosis Code-Based Claims to Identify Pulmonary NTM Disease in Bronchiectasis Patients.

Nontuberculous mycobacteria infection is increasing in incidence and can lead to chronic, debilitating pulmonary disease. We investigated the accuracy of diagnosis code-based nontuberculous mycobacteria lung disease claims among Medicare beneficiaries in the United States. We observed that these claims have moderate validity, but given their low sensitivity, incidence might be underestimated.

Five-year reintervention after endovascular abdominal aortic aneurysm repair in the Vascular Quality Initiative.

OBJECTIVE: Patients who undergo endovascular abdominal aortic aneurysm repair (EVR) remain at risk for reintervention and rupture. We sought to define the 5-year rate of reintervention and rupture after EVR in the Vascular Quality Initiative (VQI). METHODS: We identified all patients in the VQI who underwent EVR from 2003 to 2015. We linked patients in the VQI to Medicare claims for long-term outcomes. We stratified patients on baseline clinical and procedural characteristics to identify those at risk for reintervention. Our primary outcomes were 5-year rates of reintervention and late aneurysm rupture after EVR. We assessed these with Kaplan-Meier survival estimation. RESULTS: We studied 12,911 patients who underwent EVR. The mean age was 75.5 years, 79.9% were male, 3.9% were black, and 89.1% of operations were performed electively. The 5-year rate of reintervention for the entire cohort was 21%, and the 5-year rate of late aneurysm rupture was 3%. Reintervention rates varied across categories of EVR urgency. Patients who underwent EVR electively had the lowest 5-year rate of reintervention at 20%. Those who underwent surgery for symptomatic aneurysms had higher rates of reintervention at 25%. Patients undergoing EVR emergently for rupture had the highest rate of reintervention, 27% at 4 years (log-rank across the three groups, P < .001). Black race and aneurysm size of 6.0 cm or greater were associated with significantly elevated reintervention rates (black, 31% vs white, 20% [log-rank, P < .001]; aneurysm size 6.0 cm or greater, 27% vs all others, <20% [log-rank, P < .001]). There were no significant associations between age or gender and the 5-year rate of reintervention. CONCLUSIONS: More than one in five Medicare patients undergo reintervention within 5 years after EVR in the VQI; late rupture remains low at 3%. Black patients, those with large aneurysms, and those who undergo EVR urgently and emergently have a higher likelihood of adverse outcomes and should be the focus of diligent long-term surveillance.

Food Insecurity is Directly Associated with the Use of Health Services for Adverse Health Events among Older Adults.

BACKGROUND: In 2018, 14.3 million US households experienced food insecurity, which has been linked to negative health outcomes such as depression and anxiety, diabetes, and hypertension. This connection is particularly important for older adults, who are at greater risk than younger adults for developing certain health conditions. OBJECTIVE: We estimated the association between food insecurity and the use of health services for adverse health events over a 12-mo observation period following survey interview for a nationally representative group of older adults participating in the congregate meal (CM) and home-delivered meal (HDM) programs. METHODS: We analyzed data from the Nutrition Services Program (NSP) Outcomes Survey matched to Medicare claims and enrollment data in 2015-2016 for a nationally representative sample of 626 CM or HDM recipients ages 67 y and older. We used logistic regression analysis controlling for demographic characteristics, prior health events, and geography to estimate the association between food insecurity and use of health services, including emergency department visits, inpatient stays, skilled nursing facility stays, and home healthcare episodes. We used ordinary least squares regression analysis to estimate the association between food insecurity and Medicare spending. RESULTS: Food insecurity was associated with an average increased likelihood of using health services for adverse health events of 16% (95% CI: 1%, 32%) for HDM participants. Food insecurity was associated with an average increased likelihood of emergency department visits of 24% (95% CI: 6%, 41%) for CM participants and 20% (95% CI: 5%, 36%) for HDM participants. There was no observed increase in likelihood of using the other health services. Food-insecure participants were less likely to have a skilled nursing facility stay. CONCLUSIONS: Food insecurity is associated with an increased likelihood of use of health services for adverse health events in older adult participants in meal service programs.

Development and validation of coding algorithms to identify patients with incident lung cancer in United States healthcare claims data.

PURPOSE: Our aim was to develop and validate a practical US healthcare claims algorithm for identifying incident lung cancer that improves on positive predictive value (PPV) and sensitivity observed in past studies. METHODS: Patients newly diagnosed with lung cancer in Surveillance, Epidemiology, and End Results (SEER) (gold standard) were linked with Medicare claims. A 5% Medicare "other cancer" sample and noncancer sample served as controls. A split-sample validation approach was used. Rules-based, regression, and machine learning models for developing algorithms were explored. Algorithms were developed in the model building subset. Rules-based algorithms and those with the highest F scores were evaluated in the validation subset. F scores were compared for 1000 bootstrap samples. Misclassification was evaluated by calculating the odds of selection by the algorithm among true positives and true negatives. RESULTS: A practical single-score algorithm derived from a logistic regression model had sensitivity = 78.22% and PPV = 78.50% (F score: 78.36). The algorithm was most likely to misclassify older patients (ages ≥80 years) or with missing data in the SEER registry, shorter follow-up time in Medicare (<3 months), insurance through Veterans Affairs, >1 cancer in SEER, or certain Charlson comorbidities (dementia, chronic pulmonary disease, liver disease, or myocardial infarction). CONCLUSION: In this dataset, a practical point-based algorithm for identifying incident lung cancer demonstrated significant and substantial improvement (7.9% and 23.9% absolute improvement in sensitivity and PPV, respectively) compared with a current standard.

Timely estimation of National Admission, readmission, and observation-stay rates in medicare patients with acute myocardial infarction, heart failure, or pneumonia using near real-time claims data.

BACKGROUND: To estimate, prior to finalization of claims, the national monthly numbers of admissions and rates of 30-day readmissions and post-discharge observation-stays for Medicare fee-for-service beneficiaries hospitalized with acute myocardial infarction (AMI), heart failure (HF), or pneumonia. METHODS: The centers for Medicare & Medicaid Services (CMS) Integrated Data Repository, including the Medicare beneficiary enrollment database, was accessed in June 2015, February 2017, and February 2018. We evaluated patterns of delay in Medicare claims accrual, and used incomplete, non-final claims data to develop and validate models for real-time estimation of admissions, readmissions, and observation stays. RESULTS: These real-time reporting models accurately estimate, within 2 months from admission, the monthly numbers of admissions, 30-day readmission and observation-stay rates for patients with AMI, HF, or pneumonia. CONCLUSIONS: This work will allow CMS to track the impact of policy decisions in real time and enable hospitals to better monitor their performance nationally.

Using Medicare claims in identifying Alzheimer's disease and related dementias.

INTRODUCTION: This study develops a measure of Alzheimer's disease and related dementias (ADRD) using Medicare claims. METHODS: Validation resembles the approach of the American Psychological Association, including (1) content validity, (2) construct validity, and (3) predictive validity. RESULTS: We found that four items-a Medicare claim recording ADRD 1 year ago, 2 years ago, 3 years ago, and a total stay of 6 months in a nursing home-exhibit a pattern of association consistent with a single underlying ADRD construct, and presence of any two of these four items predict a direct measure of cognitive function and also future claims for ADRD. DISCUSSION: Our four items are internally consistent with the measurement of a single quantity. The presence of any two items do a better job than a single claim when predicting both a direct measure of cognitive function and future ADRD claims.

Risk of incident claims for chemotherapy-induced peripheral neuropathy among women with breast cancer in a Medicare population.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common and disabling consequence of neurotoxic therapies, yet factors that modulate the development and clinical impact of CIPN are poorly understood. This epidemiological analysis identifies risk factors for the incidence of CIPN. METHODS: This retrospective analysis of Surveillance, Epidemiology, and End Results-Medicare data examined predictors of incident CIPN claims among 11,149 women aged 66 years or older with American Joint Commission on Cancer (AJCC) stage II to IV breast cancer (and no secondary cancer diagnosis or preexisting neuropathy) who received chemotherapy. RESULTS: Overall, new CIPN claims occurred for 8.3% of patients within 1 year of starting chemotherapy. Risk emerged approximately 3 months after the start of chemotherapy and increased throughout 1 year. Paclitaxel as part of first-line therapy increased CIPN risk 2.7-fold in comparison with nonneurotoxic agents (15.9% vs 5.0%), with lower incidence rates for carboplatin and paclitaxel (11.9%), carboplatin and docetaxel (9.3%), carboplatin alone (7.7%), and docetaxel alone (6.6%). The CIPN incidence rate was higher for women who at the time of their breast cancer diagnosis were relatively young (within this Medicare sample), were at AJCC stage II or III, were married or had an equivalent status, and had fewer comorbidities, but it did not differ by race/ethnicity or poverty level. CONCLUSIONS: These Medicare claims database findings indicate that women aged 66 years or older with breast cancer are susceptible to CIPN from taxane and/or platinum compounds, with risk emerging approximately 3 months into treatment. Prospective studies of symptom emergence and clinical response (eg, stopping chemotherapy and adjunctive treatments) are indicated to determine how best to inform patients of this risk and to manage CIPN in this population.

A comparison of reintervention rates after endovascular aneurysm repair between the Vascular Quality Initiative registry, Medicare claims, and chart review.

OBJECTIVE: The accurate measurement of reintervention after endovascular aneurysm repair (EVAR) is critical during postoperative surveillance. The purpose of this study was to compare reintervention rates after EVAR from three different data sources: the Vascular Quality Initiative (VQI) alone, VQI linked to Medicare claims (VQI-Medicare), and a "gold standard" of clinical chart review supplemented with telephone interviews. METHODS: We reviewed the medical records of 729 patients who underwent EVAR at our institution between 2003 and 2013. We excluded patients without follow-up reported to the VQI (n = 68 [9%]) or without Medicare claims information (n = 114 [16%]). All patients in the final analytic cohort (n = 547) had follow-up information available from all three data sources (VQI alone, VQI linked to Medicare, and chart review). We then compared reintervention rates between the three data sources. Our primary end points were the agreement between the three data sources and the Kaplan-Meier estimated rate of reintervention at 1 year, 2 years, and 3 years after EVAR. For gold standard assessment, we supplemented chart review with telephone interview as necessary to assess reintervention. RESULTS: VQI data alone identified 12 reintervention events in the first year after EVAR. Chart review confirmed all 12 events and identified 18 additional events not captured by the VQI. VQI-Medicare data successfully identified all 30 of these events within the first year. VQI-Medicare also documented four reinterventions in this time period that did not occur on the basis of patient interview (4/547 [0.7%]). The agreement between chart review and VQI-Medicare data at 1 year was excellent (κ = 0.93). At 3 years, there were 81 (18%) reinterventions detected by VQI-Medicare and 70 (16%) detected by chart review for a sensitivity of 92%, specificity of 96%, and κ of 0.80. Kaplan-Meier survival analysis demonstrated similar reintervention rates after 3 years between VQI-Medicare and chart review (log-rank, P = .59). CONCLUSIONS: Chart review after EVAR demonstrated a 6% 1-year and 16% 3-year reintervention rate, and almost all (92%) of these events were accurately captured using VQI-Medicare data. Linking VQI data with Medicare claims allows an accurate assessment of reintervention rates after EVAR without labor-intensive physician chart review.

Development of algorithms for identifying fatal cardiovascular disease in Medicare claims.

BACKGROUND: Cause of death is often not available in administrative claims data. OBJECTIVE: To develop claims-based algorithms to identify deaths due to fatal cardiovascular disease (CVD; ie, fatal coronary heart disease [CHD] or stroke), CHD, and stroke. METHODS: Reasons for Geographic and Racial Differences in Stroke (REGARDS) study data were linked with Medicare claims to develop the algorithms. Events adjudicated by REGARDS study investigators were used as the gold standard. Stepwise selection was used to choose predictors from Medicare data for inclusion in the algorithms. C-index, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were used to assess algorithm performance. Net reclassification index (NRI) was used to compare the algorithms with an approach of classifying all deaths within 28 days following hospitalization for myocardial infarction and stroke to be fatal CVD. RESULTS: Data from 2,685 REGARDS participants with linkage to Medicare, who died between 2003 and 2013, were analyzed. The C-index for discriminating fatal CVD from other causes of death was 0.87. Using a cut-point that provided the closest observed-to-predicted number of fatal CVD events, the sensitivity was 0.64, specificity 0.90, PPV 0.65, and NPV 0.90. The algorithms resulted in positive NRIs compared with using deaths within 28 days following hospitalization for myocardial infarction and stroke. Claims-based algorithms for discriminating fatal CHD and fatal stroke performed similarly to fatal CVD. CONCLUSION: The claims-based algorithms developed to discriminate fatal CVD events from other causes of death performed better than the method of using hospital discharge diagnosis codes.

Regional and Temporal Variations in Comorbidity Among US Dialysis Patients: A Longitudinal Study of Medicare Claims Data.

Medicare claims data are commonly used to query comorbidities for case-mix adjustment in research of patients with end-stage renal disease (ESRD) in the United States. These adjustments may affect reimbursement and quality rating through comparative profiling and ranking of dialysis facilities. We studied regional and temporal variations in comorbidity from claims data in the United States Renal Data System. Patients with a previous 1-year Medicare history who initiated dialysis therapy between 2006 and 2009 were examined with a follow-up period until 2012. By linking pre- and post-ESRD Medicare claims with the Dartmouth Atlas, we carried out a longitudinal data analysis with multivariable adjustment to investigate regional and temporal variations in the Liu comorbidity index. We identified 23 336 incident hemodialysis patients who were covered by Medicare the year prior to dialysis initiation and had survived with complete 3 years of follow-up data. With the United States divided into 4 geographic regions, the Western region was found to have the lowest Liu index over all 3 follow-up years, compared with the respective years in the other regions (Midwest, Northeast, and South). In comparison with the first year, the Liu index dropped significantly during the second and third years of follow-up across all 4 regions. Significant regional and temporal variations observed in the comorbidity index cannot be explained by differences in reimbursement (average per state) or predialysis comorbidity. Based on our exploratory study, future studies should focus on identifying the factors and reasons for these variations which have the potential to affect health care policy and research.

Defining hip fracture with claims data: outpatient and provider claims matter.

Medicare claims are commonly used to identify hip fractures, but there is no universally accepted definition. We found that a definition using inpatient claims identified fewer fractures than a definition including outpatient and provider claims. Few additional fractures were identified by including inconsistent diagnostic and procedural codes at contiguous sites. INTRODUCTION: Medicare claims data is commonly used in research studies to identify hip fractures, but there is no universally accepted definition of fracture. Our purpose was to describe potential misclassification when hip fractures are defined using Medicare Part A (inpatient) claims without considering Part B (outpatient and provider) claims and when inconsistent diagnostic and procedural codes occur at contiguous fracture sites (e.g., femoral shaft or pelvic). METHODS: Participants included all long-stay nursing home residents enrolled in Medicare Parts A and B fee-for-service between 1/1/2008 and 12/31/2009 with follow-up through 12/31/2011. We compared the number of hip fractures identified using only Part A claims to (1) Part A plus Part B claims and (2) Part A and Part B claims plus discordant codes at contiguous fracture sites. RESULTS: Among 1,257,279 long-stay residents, 40,932 (3.2%) met the definition of hip fracture using Part A claims, and 41,687 residents (3.3%) met the definition using Part B claims. 4566 hip fractures identified using Part B claims would not have been captured using Part A claims. An additional 227 hip fractures were identified after considering contiguous fracture sites. CONCLUSIONS: When ascertaining hip fractures, a definition using outpatient and provider claims identified 11% more fractures than a definition with only inpatient claims. Future studies should publish their definition of fracture and specify if diagnostic codes from contiguous fracture sites were used.

Identification of Heart Failure Events in Medicare Claims: The Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: We examined the accuracy of Medicare heart failure (HF) diagnostic codes in the identification of acute decompensated (ADHF and chronic stable (CSHF) HF. METHODS AND RESULTS: Hospitalizations were identified from medical discharge records for Atherosclerosis Risk in Communities (ARIC) study participants with linked Medicare Provider Analysis and Review (MedPAR) files for the years 2005-2009. The ARIC study classification of ADHF and CSHF, based on adjudicated review of medical records, was considered to be the criterion standard. A total 8,239 ARIC medical records and MedPAR records meeting fee-for-service (FFS) criteria matched on unique participant ID and date of discharge (68.5% match). Agreement between HF diagnostic codes from the 2 data sources found in the matched records for codes in any position (κ > 0.9) was attenuated for primary diagnostic codes (κ < 0.8). Sensitivity of HF diagnostic codes found in Medicare claims in the identification of ADHF and CSHF was low, especially for the primary diagnostic codes. CONCLUSION: Matching of hospitalizations from Medicare claims with those obtained from abstracted medical records is incomplete, even for hospitalizations meeting FFS criteria. Within matched records, HF diagnostic codes from Medicare show excellent agreement with HF diagnostic codes obtained from medical record abstraction. The Medicare data may, however, overestimate the occurrence of hospitalized ADHF or CSHF.

Comorbidity ascertainment from the ESRD Medical Evidence Report and Medicare claims around dialysis initiation: a comparison using US Renal Data System data.

BACKGROUND: The end-stage renal disease Medical Evidence Report serves as a source of comorbid condition data for risk adjustment of quality metrics. We sought to compare comorbid condition data in the Medical Evidence Report around dialysis therapy initiation with diagnosis codes in Medicare claims. STUDY DESIGN: Observational cohort study using US Renal Data System data. SETTING & PARTICIPANTS: Medicare-enrolled elderly (≥66 years) patients who initiated maintenance dialysis therapy July 1 to December 31, 2007, 2008, or 2009. INDEX TESTS: 12 comorbid conditions ascertained from claims during the 6 months before dialysis therapy initiation, the Medical Evidence Report, and claims during the 3 months after dialysis therapy initiation. REFERENCE TEST: None. RESULTS: Comorbid condition prevalence according to claims before dialysis therapy initiation generally exceeded prevalence according to the Medical Evidence Report. The κ statistics for comorbid condition designations other than diabetes ranged from 0.06 to 0.43. Discordance of designations was associated with age, race, sex, and end-stage renal disease Network. During 23,930 patient-years of follow-up from 4 to 12 months after dialysis therapy initiation (8,930 deaths), designations from claims during the 3 months after initiation better discriminated risk of death than designations from the Medical Evidence Report (C statistics of 0.674 vs 0.616). Between the Medical Evidence Report and claims, standardized mortality ratios changed by >10% for more than half the dialysis facilities. LIMITATIONS: Neither the Medical Evidence Report nor diagnosis codes in claims constitute a gold standard of comorbid condition data; results may not apply to nonelderly patients or patients without Medicare coverage. CONCLUSIONS: Discordance of comorbid condition designations from the Medical Evidence Report and claims around dialysis therapy initiation was substantial and significantly associated with patient characteristics, including location. These patterns may engender bias in risk-adjusted quality metrics. In lieu of the Medical Evidence Report, claims during the 3 months after dialysis therapy initiation may constitute a useful source of comorbid condition data.

Risk of venous thromboembolism after shoulder arthroplasty in the Medicare population.

BACKGROUND: Chemoprophylaxis for venous thromboembolism (VTE) is considered standard of care after lower but not after upper extremity arthroplasty. Medicare claims data were analyzed to determine the national incidence of symptomatic VTE after shoulder arthroplasty during the index surgical admission and after discharge. METHODS: Incidence of VTE was compared between shoulder arthroplasty and lower extremity arthroplasty, and patient-specific risk factors for pulmonary embolism were determined for shoulder arthroplasty. Finally, the incidence of surgical site bleeding was determined for each type of procedure. RESULTS: VTE complications occurred in 1.2% of lower extremity and 0.53% of shoulder arthroplasties. Patient factors that were associated with an increased risk of VTE included a principal diagnosis of fracture, history of VTE, cardiac arrhythmia, presence of a metastatic tumor, coagulopathy, congestive heart failure, alcohol abuse, and obesity. Adjusted rates of VTE were generally higher for lower extremity compared with shoulder arthroplasties. Prevalence of readmission for VTE was higher for shoulder hemiarthroplasty than for total shoulder arthroplasty. Wound hematoma rates were similar between shoulder and lower extremity procedures. CONCLUSIONS: VTE rates after shoulder arthroplasty were generally lower than those after lower extremity arthroplasty. We believe that the risk of bleeding combined with the lower rates of VTE with existing lower rates of chemoprophylaxis does not warrant the routine use of anticoagulation. Use of mechanical prophylaxis combined with aspirin may be sufficient for shoulder arthroplasty patients who are not at increased risk of VTE. Chemoprophylaxis with agents other than aspirin may be warranted in patients with a demonstrated risk of VTE.

Use of reverse total shoulder arthroplasty in the Medicare population.

BACKGROUND: Reverse shoulder arthroplasty (RSA) has been Food and Drug Administration approved in the United States since 2004 but did not obtain a unique code until 2010. Therefore, the use of this popular procedure has yet to be reported. The purpose of this study was to examine the use and reimbursement of RSA compared with total shoulder arthroplasty (TSA) and shoulder hemiarthroplasty (SHA). METHODS: We analyzed the 100% sample of the 2011 Medicare Part A claims data for patients aged 65 years or older. Patient demographic characteristics, diagnoses, provider information, reimbursements, and lengths of stay were extracted from the claims data. RESULTS: In 2011, a total of 31,002 shoulder arthroplasty procedures were performed; 37% were RSAs, 42% were TSAs, and 21% were SHAs. Osteoarthritis was the primary diagnosis code in 91% of TSAs, 37% of SHAs, and 45% of RSAs. A primary diagnosis of osteoarthritis with no secondary code for rotator cuff tear was found in 22% of patients undergoing RSA. The mean length of stay for RSA (2.6 days; SD, 2.1 days) was longer than that for TSA (2.1 days; SD, 1.5 days) and shorter than that for SHA (3.5 days; SD, 3.6 days) (P < .001). Lower-volume surgeons (<10 arthroplasties per year) performed most shoulder arthroplasties: 57% of RSAs, 65% of TSAs, and 97% of SHAs. Seventy percent of RSAs were implanted by surgeons who performed more RSAs than TSAs and SHAs combined. CONCLUSIONS: RSA is performed with similar frequency to TSA and almost twice as much as SHA in the Medicare population. Lower-volume surgeons perform most RSAs, and a majority of surgeons perform more RSAs than all anatomic shoulder arthroplasties combined.

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.