Publications

2021

Strom JB, Xu J, Orkaby AR, et al. Identification of Frailty Using a Claims-Based Frailty Index in the CoreValve Studies: Findings from the EXTEND-FRAILTY Study. Journal of the American Heart Association. 2021;10(19):e022150. doi:10.1161/JAHA.121.022150

Background In aortic valve disease, the relationship between claims-based frailty indices (CFIs) and validated measures of frailty constructed from in-person assessments is unclear but may be relevant for retrospective ascertainment of frailty status when otherwise unmeasured. Methods and Results We linked adults aged ≥65 years in the US CoreValve Studies (linkage rate, 67%; mean age, 82.7±6.2 years, 43.1% women), to Medicare inpatient claims, 2011 to 2015. The Johns Hopkins CFI, validated on the basis of the Fried index, was generated for each study participant, and the association between CFI tertile and trial outcomes was evaluated as part of the EXTEND-FRAILTY substudy. Among 2357 participants (64.9% frail), higher CFI tertile was associated with greater impairments in nutrition, disability, cognition, and self-rated health. The primary outcome of all-cause mortality at 1 year occurred in 19.3%, 23.1%, and 31.3% of those in tertiles 1 to 3, respectively (tertile 2 versus 1: hazard ratio, 1.22; 95% CI, 0.98-1.51; P=0.07; tertile 3 versus 1: hazard ratio, 1.73; 95% CI, 1.41-2.12; P<0.001). Secondary outcomes (bleeding, major adverse cardiovascular and cerebrovascular events, and hospitalization) were more frequent with increasing CFI tertile and persisted despite adjustment for age, sex, New York Heart Association class, and Society of Thoracic Surgeons risk score. Conclusions In linked Medicare and CoreValve study data, a CFI based on the Fried index consistently identified individuals with worse impairments in frailty, disability, cognitive dysfunction, and nutrition and a higher risk of death, hospitalization, bleeding, and major adverse cardiovascular and cerebrovascular events, independent of age and risk category. While not a surrogate for validated metrics of frailty using in-person assessments, use of this CFI to ascertain frailty status among patients with aortic valve disease may be valid and prognostically relevant information when otherwise not measured.

Butala NM, Raja A, Xu J, et al. Association of Frailty With Treatment Selection and Long-Term Outcomes Among Patients With Chronic Limb-Threatening Ischemia. Journal of the American Heart Association. 2021;10(24):e023138. doi:10.1161/JAHA.121.023138

Background The optimal treatment strategy for patients with chronic limb-threatening ischemia (CLTI) is often unclear. Frailty has emerged as an important factor that can identify patients at greater risk of poor outcomes and guide treatment selection, but few studies have explored its utility among the CLTI population. We examine the association of a health record-based frailty measure with treatment choice and long-term outcomes among patients hospitalized with CLTI. Methods and Results We included patients aged >65 years hospitalized with CLTI in the Medicare Provider Analysis and Review data set between October 1, 2009 and September 30, 2015. The primary exposure was frailty, defined by the Claims-based Frailty Indicator. Baseline frailty status and revascularization choice were examined using logistic regression. Cox proportional hazards regression was used to determine the association between frailty and death or amputation, stratifying by treatment strategy. Of 85 060 patients, 35 484 (42%) were classified as frail. Frail patients had lower likelihood of revascularization (adjusted odds ratio [OR], 0.78; 95% CI, 0.75‒0.82). Among those revascularized, frailty was associated with lower likelihood of surgical versus endovascular treatment (adjusted OR, 0.76; CI, 0.72‒0.81). Frail patients experienced increased risk of amputation or death, regardless of revascularization status (revascularized: adjusted hazard ratio [HR], 1.34; CI, 1.30‒1.38; non-revascularized: adjusted HR, 1.22; CI, 1.17‒1.27). Among those revascularized, frailty was independently associated with amputation or death irrespective of revascularization strategy (surgical: adjusted HR, 1.36; CI, 1.31‒1.42; endovascular: aHR, 1.29; CI, 1.243‒1.35). Conclusions Among patients hospitalized with CLTI, frailty is an important independent predictor of revascularization strategy and longitudinal adverse outcomes.

Strom JB, Xu J, Orkaby AR, et al. Role of Frailty in Identifying Benefit From Transcatheter Versus Surgical Aortic Valve Replacement. Circulation. Cardiovascular quality and outcomes. 2021;14(12):e008566. doi:10.1161/CIRCOUTCOMES.121.008566

BACKGROUND: Frailty is associated with a higher risk for adverse outcomes after aortic valve replacement (AVR) for severe aortic valve stenosis, but whether or not frail patients derive differential benefit from transcatheter (TAVR) versus surgical (SAVR) AVR is uncertain.

METHODS: We linked adults ≥65 years old in the US CoreValve HiR trial (High-Risk) or SURTAVI trial (Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk Patients) to Medicare claims, February 2, 2011, to September 30, 2015. Two frailty measures, a deficit-based and phenotype-based frailty index (FI), were generated. The treatment effect of TAVR versus SAVR was evaluated within FI tertiles for the primary end point of death and nondeath secondary outcomes, using multivariable Cox regression.

RESULTS: Of 1442 (linkage rate =60.0%) individuals included, 741 (51.4%) individuals received TAVR and 701 (48.6%) received SAVR (mean age 81.8±6.1 years, 44.0% female). Although 1-year death rates in the highest FI tertiles (deficit-based FI 36.7% and phenotype-based FI 33.8%) were 2- to 3-fold higher than the lowest tertiles (deficit-based FI 13.4%; hazard ratio, 3.02 [95% CI, 2.26-4.02], P<0.001; phenotype-based FI 17.9%; hazard ratio, 2.05 [95% CI, 1.58-2.67], P<0.001), there were no significant differences in the relative or absolute treatment effect of SAVR versus TAVR across FI tertiles for all death, nondeath, and functional outcomes (all interaction P>0.05). Results remained consistent across individual trials, frailty definitions, and when considering the nonlinked trial data.

CONCLUSIONS: Two different frailty indices based on Fried and Rockwood definitions identified individuals at higher risk of death and functional impairment but no differential benefit from TAVR versus SAVR.

2020

Yang JX, Stevenson MJ, Valsdottir L, et al. Association between procedure appropriateness and patient-reported outcomes after percutaneous coronary intervention. Heart (British Cardiac Society). 2020;106(6):441-446. doi:10.1136/heartjnl-2019-315835

OBJECTIVE: The Appropriate Use Criteria (AUC) has been used to identify individuals who are likely to benefit from percutaneous coronary intervention (PCI) for stable ischaemic heart disease. However, whether physicians reliably grade PCI appropriateness and whether AUC categories stratify symptomatic improvement in real-world practice are unclear.

METHODS: Patient-reported outcomes measures (PROMs) for angina (Seattle Angina Questionnaire (SAQ-7)), dyspnoea (Rose Dyspnea Scale (RDS)) and depression (Patient Health Questionnaire-2 (PHQ-2)) were collected on patients undergoing elective coronary angiography at an academic medical centre. Retrospectively, two physicians independently determined PCI appropriateness by the AUC criteria.

RESULTS: Inter-rater agreement on appropriateness was moderate (κ=0.48, 95% CI 0.32 to 0.63). Of PCI procedures evaluated, 57 (47.1%) were appropriate (A-PCI), 62 (51.2%) were maybe appropriate (MA-PCI) and 2 (1.6%) were rarely appropriate. At baseline, A-PCI compared with MA-PCI patients had worse RDS scores (2.0 vs 1.2, p=0.01). At 30 days, the change in SAQ-7 summary score was similar between groups (A-PCI vs MA-PCI, +27.1 vs +20.7, p=0.11). The mean change in RDS score was greater in A-PCI than MA-PCI (-1.0 vs -0.5, p for group by time interaction=0.03). PHQ-2 scores were similar and did not improve at 30 days.

CONCLUSION: In patients undergoing PCI with PROMs collected before and 30 days after PCI, similar improvements in angina were observed regardless of appropriateness. Inter-rater agreement on PCI appropriateness was only moderate. Use of PROMs may improve reliability of physician assessments of PCI appropriateness.

BACKGROUND: Whether passively collected data can substitute for adjudicated outcomes to reproduce the magnitude and direction of treatment effect observed in cardiovascular clinical trials is not well known.

METHODS: We linked adults ≥65 years of age in the HiR (US CoreValve Pivotal High Risk) and SURTAVI trials (Surgical or Transcatheter Aortic Valve Replacement in Intermediate-Risk Patients) to 100% Medicare inpatient claims, January 1, 2011, to December 31, 2016. Primary (eg, death and stroke) and secondary trial end points were compared across treatment arms (eg, transcatheter aortic valve replacement [TAVR] versus surgical aortic valve replacement [SAVR]) using trial-adjudicated outcomes versus outcomes derived from claims at 1 year (HiR) or 2 years (SURTAVI).

RESULTS: Among 600 linked HiR participants (linkage rate, 80.0%), the rate of the trial's primary end point of all-cause mortality occurred in 13.7% of patients receiving TAVR and 16.4% of patients receiving SAVR at 1 year by using both trial data (hazard ratio, 0.84 [95% CI, 0.65-1.09]; P=0.33) and claims data (hazard ratio, 0.86 [95% CI, 0.66-1.11]; P=0.34; interaction P value=0.80). Noninferiority of TAVR relative to SAVR was seen by using both trial- and claims-based outcomes (Pnoninferiority<0.001 for both). Among 1005 linked SURTAVI trial participants (linkage rate, 60.5%), the trial's primary end point was 12.9% for TAVR and 13.1% for SAVR using trial data (hazard ratio, 1.08 [95% CI, 0.79-1.48]; P=0.90), and 11.3% for TAVR and 12.5% for SAVR patients using claims data (hazard ratio, 1.02 [95% CI, 0.73-1.41]; P=0.58; interaction P value=0.89). TAVR was noninferior to SAVR when compared using both trial and claims (Pnoninferiority<0.001 for both). Rates of procedural secondary outcomes (eg, aortic valve reintervention, pacemaker rates) were more closely concordant between trial and claims data than nonprocedural outcomes (eg, stroke, bleeding, cardiogenic shock).

CONCLUSIONS: In the HiR and SURTAVI trials, ascertainment of trial primary end points using claims reproduced both the magnitude and direction of treatment effect in comparison with adjudicated event data, but nonfatal and nonprocedural secondary outcomes were not as well reproduced. Use of claims to substitute for adjudicated outcomes in traditional trial treatment comparisons may be valid and feasible for all-cause mortality and certain procedural outcomes but may be less suitable for other end points.

Strom JB, Gelfand E V, Markson LJ, Tsao CA, Manning WJ. Relation of Transthoracic Echocardiographic Aortic Regurgitation to Pressure Half-time and All-Cause Mortality. The American journal of cardiology. 2020;135:113-119. doi:10.1016/j.amjcard.2020.08.043

To evaluate the relation of aortic regurgitation (AR) pressure half-time (PHT) on transthoracic echocardiography (TTE) and all-cause mortality, we screened 118,647 baseline TTE reports from 2000 to 2017, to identify patients with any AR and PHT data. Patients with infective endocarditis or previous aortic valve replacement were excluded. The relation of baseline PHT on time to all-cause mortality was evaluated using Cox regression. A total of 2,653 patients were included (73.1 ± 14.3 years; 53.8% female; PHT, 530 ± 162 ms). Patients with shorter PHTs more frequently had 3-4+ AR (PHT ≤ 200 ms vs > 500 ms, 17.9% vs 0.6%, p < 0.0001). Diastolic parameters (E/e', E/A ratio, mitral valve deceleration time, and pulmonary artery systolic pressure) all significantly correlated with PHT (all p < 0.05). Over a median (IQR) follow-up of 8 (4 to 11 years), there were 799 (30.1%) deaths at a median (IQR) of 1.9 (0.4 to 4.3) years. On a univariate basis, a PHT ≤ 320 ms or > 750 ms was significantly related to increased mortality, even amongst those with nonsevere AR. After multivariable adjustment (in particular for E/e'), PHT was no longer significantly related to death. In conclusion, in this large, single center, retrospective study, AR PHT was not independently related to mortality. While a PHT ≤ 320 ms was associated with increased mortality in patients without severe AR, this relation was no longer significant after adjusting for diastolic functional variables. Thus, a PHT ≤ 320 ms in patients without significant AR may indicate prognostically-relevant diastolic dysfunction.

Butala NM, Strom JB, Faridi KF, et al. Validation of Administrative Claims to Ascertain Outcomes in Pivotal Trials of Transcatheter Aortic Valve Replacement. JACC. Cardiovascular interventions. 2020;13(15):1777-1785. doi:10.1016/j.jcin.2020.03.049

OBJECTIVES: The aim of this study was to evaluate the performance of administrative claims in ascertaining trial clinical events committee-adjudicated outcomes in the U.S. CoreValve studies.

BACKGROUND: Real-world data offer tremendous opportunity to improve outcome ascertainment in clinical trials. However, little is known about the validity of outcomes ascertained using real-world data to capture trial endpoints.

METHODS: Patients enrolled in 3 pivotal trials and 2 pre-market continued-access studies evaluating transcatheter aortic valve replacement were linked to Medicare fee-for-service inpatient claims. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa agreement statistic of claims to detect clinical endpoints and procedural complications in trial patients were calculated.

RESULTS: Claims accurately identified trial-adjudicated deaths (sensitivity, specificity, PPV, and NPV all >99.6%; kappa 1.00). Claims had good performance in identifying trial-adjudicated permanent pacemaker implantation (sensitivity 92.2%, specificity 99.1%, PPV 96.1%, NPV 98.2%, kappa 0.93) and aortic valve reintervention (sensitivity 84.4%, specificity 99.6%, PPV 69.1%, NPV 99.8%, kappa 0.76). Claims had more modest performance in ascertaining trial-adjudicated myocardial infarction (sensitivity 63.6%, specificity 97.2%, PPV 29.9%, NPV 99.3%, kappa 0.39) and acute kidney injury (sensitivity 70.2%, specificity 85.4%, PPV 38.2%, NPV 95.7%, kappa 0.41) and the poorest performance for identifying trial-adjudicated bleeding events (sensitivity 86.4%, specificity 36.8%, PPV 35.0%, NPV 86.3%, kappa 0.16).

CONCLUSIONS: Compared with trial-adjudicated outcomes, claims data performed well in ascertaining death and outcomes with procedural billing codes and more modestly in identifying other outcomes. Claims may be cautiously and selectively used to augment data collection in future cardiovascular device trials.