Comparison of Medicare Claims-based Proxy Measures of Poor Function and Associations With Treatment Receipt and Mortality in Older Colon Cancer Patients

Longitudinal trajectories of a claims-based frailty measure during adjuvant chemotherapy in women with stage I-III breast cancer

BACKGROUND

Frailty is a dynamic syndrome characterized by reduced physiological reserve to maintain homeostasis. Prospective studies have reported frailty worsening in women with breast cancer during chemotherapy, with improvements following treatment. We evaluated whether the Faurot frailty index, a validated claims-based frailty measure, could identify changes in frailty during chemotherapy treatment and identified predictors of trajectory patterns.

METHODS

We included women (65+ years) with stage I-III breast cancer undergoing adjuvant chemotherapy in the SEER-Medicare database (2003-2019). We estimated the Faurot frailty index (range: 0-1; higher scores indicate greater frailty) at chemotherapy initiation, 4 months postinitiation, and 10 months postinitiation. Changes in frailty were compared to a matched noncancer comparator cohort. We identified patterns of frailty trajectories during the year following chemotherapy initiation using K-means clustering.

RESULTS

Twenty-one thousand five hundred and ninety-nine women initiated adjuvant chemotherapy. Mean claims-based frailty increased from 0.037 at initiation to 0.055 4 months postchemotherapy initiation and fell to 0.049 10 months postinitiation. Noncancer comparators experienced a small increase in claims-based frailty over time (0.055-0.062). We identified 6 trajectory patterns: a robust group (78%), 2 resilient groups (16%), and 3 nonresilient groups (6%). Black women and women with claims for home hospital beds, wheelchairs, and Parkinson's disease were more likely to experience nonresilient trajectories.

CONCLUSIONS

We observed changes in a claims-based frailty index during chemotherapy that are consistent with prior studies using clinical measures of frailty and identified predictors of nonresilient frailty trajectories. Our study demonstrates the feasibility of using claims-based frailty indices to assess changes in frailty during cancer treatment.

Performance of a Claims-Based Frailty Proxy Using Varying Frailty Ascertainment Lookback Windows

BACKGROUND

Frailty is an aging-related syndrome of reduced physiological reserve to maintain homeostasis. The Faurot frailty index has been validated as a Medicare claims-based proxy for predicting frailty using billing information from a user-specified ascertainment window.

OBJECTIVES

We assessed the validity of the Faurot frailty index as a predictor of the frailty phenotype and 1-year mortality using varying frailty ascertainment windows.

RESEARCH DESIGN

We identified older adults (66+ y) in Round 5 (2015) of the National Health and Aging Trends Study with Medicare claims linkage. Gold standard frailty was assessed using the frailty phenotype. We calculated the Faurot frailty index using 3, 6, 8, and 12 months of claims prior to the survey or all-available lookback. Model performance for each window in predicting the frailty phenotype was assessed by quantifying calibration and discrimination. Predictive performance for 1-year mortality was assessed by estimating risk differences across claims-based frailty strata.

RESULTS

Among 4253 older adults, the 6 and 8-month windows had the best frailty phenotype calibration (calibration slopes: 0.88 and 0.87). All-available lookback had the best discrimination (C-statistic=0.780), but poor calibration. Mortality associations were strongest using a 3-month window and monotonically decreased with longer windows. Subgroup analyses revealed worse performance in Black and Hispanic individuals than counterparts.

CONCLUSIONS

The optimal ascertainment window for the Faurot frailty index may depend on the clinical context, and researchers should consider tradeoffs between discrimination, calibration, and mortality. Sensitivity analyses using different durations can enhance the robustness of inferences. Research is needed to improve prediction across racial and ethnic groups.

Translation of a Claims-Based Frailty Index From the International Classification of Diseases, Ninth Revision, Clinical Modification to the Tenth Revision

The Faurot frailty index (FFI) is a validated algorithm that uses enrollment and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based billing information from Medicare claims data as a proxy for frailty. In October 2015, the US health-care system transitioned from the ICD-9-CM to the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM). Applying the Centers for Medicare and Medicaid Services General Equivalence Mappings, we translated diagnosis-based frailty indicator codes from the ICD-9-CM to the ICD-10-CM, followed by manual review. We used interrupted time-series analysis of Medicare data to assess the comparability of the pre- and posttransition FFI scores. In cohorts of beneficiaries enrolled in January 2015-2017 with 8-month frailty look-back periods, we estimated associations between the FFI and 1-year risk of aging-related outcomes (mortality, hospitalization, and admission to a skilled nursing facility). Updated indicators had similar prevalences as pretransition definitions. The median FFI scores and interquartile ranges (IQRs) for the predicted probability of frailty were similar before and after the International Classification of Diseases transition (pretransition: median, 0.034 (IQR, 0.02-0.07); posttransition: median, 0.038 (IQR, 0.02-0.09)). The updated FFI was associated with increased risks of mortality, hospitalization, and skilled nursing facility admission, similar to findings from the ICD-9-CM era. Studies of medical interventions in older adults using administrative claims should use validated indices, like the FFI, to mitigate confounding or assess effect-measure modification by frailty.

Prognosis of older adults with chronic lymphocytic leukemia: A Surveillance, Epidemiology, and End Results-Medicare cohort study

INTRODUCTION

While prognosis for patients with chronic lymphocytic leukemia (CLL) has improved over time in younger adults, only modest improvements have occurred in older adults. We conducted a descriptive study of prognosis in older adults with CLL.

MATERIALS AND METHODS

We used data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database from 2003 to 2016. We identified older adults (≥66 years) diagnosed with primary CLL between 2004 and 2015 (Overall Cohort). A subset who initiated CLL-directed therapy during the year following diagnosis was also identified (Treated Cohort). Both cohorts were matched to Medicare beneficiaries without cancer based on age, sex, and region. For each year from 2004 to 2013, three-year survival for patients with CLL and non-cancer comparators was described using Kaplan-Meier analysis. Inverse probability weighted Cox regression models were used to compare survival in the CLL and non-cancer comparator cohorts, accounting for demographic information and comorbidity and frailty indices. Among older adults with CLL, ten-year cause-specific cumulative mortality was estimated using Aalen-Johansen estimators that accounted for competing risks. Predictors of cause-specific mortality, including comorbidity and frailty burden, were assessed using sub-distribution hazards models.

RESULTS

In the Overall Cohort, three-year survival increased non-monotonically from 71.4% in 2004 to 73.4% in 2013, with a peak of 74.4% in 2011, and was lower than survival in non-cancer comparators (78.3% in 2004 to 83.2% in 2013). In the Treated Cohort, three-year survival was 56.3% in 2004 and 56.5% in 2013, with a peak of 64.2% in 2011. Cox models suggested that survival in the Treated Cohort was approaching survival in non-cancer comparators after 2011 (hazard ratio = 1.04, 95% confidence interval, 0.93-1.17). Ten-year cumulative mortality was 68.6% in the Overall Cohort and 81.7% in the Treated Cohort, with most deaths attributed to non-CLL causes. In the sub-distribution hazards models, age, year of diagnosis, frailty, and comorbidities were all associated with prognosis.

DISCUSSION

Prognosis in older adults has been stable over time and most patients with CLL die from non-CLL causes. CLL-directed treatment decision-making in older adults should consider age-related factors, such as comorbidity and frailty.

Adaptability of High Dimensional Propensity Score Procedure in the Transition from ICD-9 to ICD-10 in the US Healthcare System

Background

High-Dimensional Propensity Score procedure (HDPS) is a data-driven approach to assist control for confounding in pharmacoepidemiologic research. The transition to the International Classification of Disease (ICD-9/10) in the US health system may pose uncertainty in applying the HDPS procedure.

Methods

We assembled a base cohort of patients in MarketScan^® Commercial Claims Database who had newly initiated celecoxib or traditional NSAIDs to compare gastrointestinal bleeding risk. We then created bootstrapped hypothetical cohorts from the base cohort with predefined patient selection patterns from the ICD eras. Three strategies for HDPS deployment were tested: 1) split the cohort by ICD era, deploy HDPS twice, and pool the relative risks (pooled RR), 2) consider codes from each ICD era as a separate data dimension and deploy HDPS in the entire cohort (data dimensions) and 3) map ICD codes from both eras to Clinical Classifications Software (CCS) concepts before deploying HDPS in the entire cohort (CCS mapping). We calculated percent bias and root-mean-squared error to compare the strategies.

Results

A similar bias reduction was observed in cohorts where patient selection pattern from each ICD era was comparable between the exposure groups. In the presence of considerable disparity in patient selection, we observed a bimodal distribution of propensity scores in the data dimensions strategy, indicating instrument-like covariates. Moreover, the CCS mapping strategy resulted in at least 30% less bias than pooled RR and data dimensions strategies (RMSE: 0.14, 0.19, 0.21, respectively) in this scenario.

Conclusion

Mapping ICD codes to a stable terminology like CCS serves as a helpful strategy to reduce residual bias when deploying HDPS in pharmacoepidemiologic studies spanning both ICD eras.

Patterns of age disparities in colon and lung cancer survival: a systematic narrative literature review

OBJECTIVES

To identify patterns of age disparities in cancer survival, using colon and lung cancer as exemplars.

DESIGN

Systematic review of the literature.

DATA SOURCES

We searched Embase, MEDLINE, Scopus and Web of Science through 18 December 2020.

ELIGIBILITY CRITERIA

We retained all original articles published in English including patients with colon or lung cancer. Eligible studies were required to be population-based, report survival across several age groups (of which at least one was over the age of 65) and at least one other characteristic (eg, sex, treatment).

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed the quality of included studies against selected evaluation domains from the QUIPS tool, and items concerning statistical reporting. We evaluated age disparities using the absolute difference in survival or mortality rates between the middle-aged group and the oldest age group, or by describing survival curves.

RESULTS

Out of 3047 references, we retained 59 studies (20 for colon, 34 for lung and 5 for both sites). Regardless of the cancer site, the included studies were highly heterogeneous and often of poor quality. The magnitude of age disparities in survival varied greatly by sex, ethnicity, socioeconomic status, stage at diagnosis, cancer site, and morphology, the number of nodes examined and treatment strategy. Although results were inconsistent for most characteristics, we consistently observed greater age disparities for women with lung cancer compared with men. Also, age disparities increased with more advanced stages for colon cancer and decreased with more advanced stages for lung cancer.

CONCLUSIONS

Although age is one of the most important prognostic factors in cancer survival, age disparities in colon and lung cancer survival have so far been understudied in population-based research. Further studies are needed to better understand age disparities in colon and lung cancer survival.

PROSPERO REGISTRATION NUMBER

CRD42020151402.

Effectiveness of adjuvant FOLFOX vs 5FU/LV in adults over age 65 with stage II and III colon cancer using a novel hybrid approach

PURPOSE

Estimates of cancer therapy effects can differ in clinical trials and clinical practice, partly due to underrepresentation of certain patient subgroups in trials. We utilize a hybrid approach, combining clinical trial and real-world data, to estimate the comparative effectiveness of two adjuvant chemotherapy regimens for colon cancer.

METHODS

We identified patients aged 66 and older enrolled in the Multicenter International Study of Oxaliplatin/5FU-LV in the Adjuvant Treatment of Colon Cancer. Similar patients were identified in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, initiating adjuvant chemotherapy with either 5-fluorouracil (5FU) alone or in combination with oxaliplatin (FOLFOX). We used logistic regression to estimate the likelihood of trial enrollment as a function of age, sex, and substage. Using inverse odds of sampling weights (IOSW), we compared 5-year mortality in patients randomized to FOLFOX vs 5FU using weighted Cox proportional hazards regression, the Nelson-Aalen estimator for cumulative hazards, and bootstrapping for 95% confidence intervals (CIs).

RESULTS

There were 690 trial participants and 3834 SEER-Medicare patients. The SEER-Medicare population was older and had a higher proportion of stage IIIB and IIIC patients than the trial. After controlling for differences between populations, the IOSW 5-year HR was 1.21 (0.89, 1.65), slightly farther from the null than the trial estimate (HR = 1.14, 95%CI: 0.87, 1.49).

CONCLUSIONS

This study supports mounting evidence of little to no incremental reduction in 5-year mortality for FOLFOX vs 5FU in older adults with stage II-III colon cancer, emphasizing the importance of combining clinical trial and real-world data to support such conclusions.

Patient Reported vs Claims Based Measures of Health for Modeling Life Expectancy in Men with Prostate Cancer

PURPOSE

Life expectancy has become a core consideration in prostate cancer care. While multiple prediction tools exist to support decision making, their discriminative ability remains modest, which hampers usage and utility. We examined whether combining patient reported and claims based health measures into prediction models improves performance.

MATERIALS AND METHODS

Using SEER (Surveillance, Epidemiology, and End Results)-CAHPS (Consumer Assessment of Healthcare Providers and Systems) we identified men 65 years old or older diagnosed with prostate cancer from 2004 to 2013 and extracted 4 types of data, including demographics, cancer information, claims based health measures and patient reported health measures. Next, we compared the performance of 5 nested competing risk regression models for other cause mortality. Additionally, we assessed whether adding new health measures to established prediction models improved discriminative ability.

RESULTS

Among 3,240 cases 246 (7.6%) died of prostate cancer while 631 (19.5%) died of other causes. The National Cancer Institute Comorbidity Index score was associated but weakly correlated with patient reported overall health (p <0.001, r=0.21). For predicting other cause mortality the 10-year area under the receiver operating characteristic curve improved from 0.721 (demographics only) to 0.755 with cancer information and to 0.777 and 0.812 when adding claims based and patient reported health measures, respectively. The full model generated the highest value of 0.820. Models based on existing tools also improved in their performance with the incorporation of new data types as predictor variables (p <0.001).

CONCLUSIONS

Prediction models for life expectancy that combine patient reported and claims based health measures outperform models that incorporate these measures separately. However, given the modest degree of improvement, the implementation of life expectancy tools should balance model performance with data availability and fidelity.

Updated Overview of the SEER-Medicare Data: Enhanced Content and Applications

BACKGROUND

The National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database was first created almost 30 years ago. Over time, additional data have been added to the SEER-Medicare database, allowing for expanded insights into the delivery of health care across the cancer continuum from screening to end of life.

METHODS

This article includes an overview of the current SEER-Medicare database, presenting potential users with an introduction to how the data can facilitate innovative epidemiologic and health services research studies. With a focus on the population 65 years and older, this article presents descriptive data on beneficiary demographics, cancer characteristics, service settings, Medicare coverage (eg, Parts A, B, C, and D), and use (number of services or bills) from 2011 to 2015.

RESULTS

From 2011 to 2015, 857 056 cancer patients and 601 470 population-based noncancer controls were added to the database. The database includes detailed tumor characteristics and clinical assessments for cancer cases, and demographics and health-care use (eg, hospitals, outpatient facilities, individual providers, hospice, home health-care providers, and pharmacies) for both cases and controls. Although characteristics varied overall between cases and controls, sufficient cancer-specific matched controls are available. Roughly 60% of cases were enrolled in fee for service at cancer diagnosis. The annual average number of claims per case was 60.7 and 92.3 during the year before and after cancer diagnosis, respectively, and 127.5 during the year before death.

CONCLUSIONS

The large sample size and diverse array of data on cancer patients and noncancer controls in the SEER-Medicare database make it a unique resource for conducting cancer health services research.

Acute pancreatitis as an early marker of pancreatic cancer and cancer stage, treatment, and prognosis

BACKGROUND

We aimed to examine the association between acute pancreatitis, a potential early symptom of pancreatic cancer, and pancreatic cancer stage, treatment, and prognosis.

METHODS

We conducted a cohort study of patients diagnosed with pancreatic cancer during 2004-2017 using population-based registry data from Denmark and Surveillance, Epidemiology, and End Results (SEER) data linked with Medicare claims from the United States (US), which include individuals aged 65 + . We ascertained information on acute pancreatitis diagnoses up to 90 days before pancreatic cancer and followed them for a maximum of five years. We assessed overall survival difference at 30 days, six months, and one, three and five years, comparing patients with and without coexistence of acute pancreatitis. Secondary outcomes were cancer stage and treatment.

RESULTS

We identified 12,522 Danish and 37,552 US patients with pancreatic cancer (median age 71 and 78 years, respectively). In the Danish cohort, 1.4 % had acute pancreatitis before pancreatic cancer vs. 5.9 % in the US cohort. After five years of follow-up, the survival difference was 6.1 % (95 % CI: [-0.4 %, 12.6 %]) in Danish and 1.7 % (95 % CI: [0.8 %, 2.7 %]) in US patients, comparing patients with and without acute pancreatitis. Patients with acute pancreatitis had lower prevalence of metastatic tumors at diagnosis (Denmark: 42.5 % vs. 48.7 %; US: 34.4 % vs. 45.9 %) and higher resection frequencies (Denmark: 20.1 % vs. 12.1 %; US: 16.1 % vs.11.3 %) than patients without acute pancreatitis.

CONCLUSIONS

Pancreatic cancer patients with acute pancreatitis diagnosed up to 90 days before cancer diagnosis had earlier stage at diagnosis and better survival than patients without acute pancreatitis.