Quantifying the Value of Reduced Health Disparities: Low-Dose Computed Tomography Lung Cancer Screening of High-Risk Individuals Within the United States

OBJECTIVE

This study aimed to measure the value of increasing lung cancer screening rates for high-risk individuals and its impact on health disparities.

METHODS

The model estimated changes in health economic outcomes if low-dose computed tomography screening increased from current to 100% compliance, following clinical guidelines. Current low-dose computed tomography screening rates were estimated by income, education, and race, using 2017-2019 Behavioral Risk Factor Surveillance System data. The model contained a decision tree module to segment the population by screening outcomes and a Markov chain module to estimate cancer progression over time. Model parameters included information on survival, quality of life, and costs related to cancer diagnosis, treatment, and adverse events. Distributional cost-effectiveness analysis estimated the net monetary value from reduced health disparities-measured using quality-adjusted life expectancy-across income, education, and race groups. Outcomes were assessed over 30 years.

RESULTS

Lung cancer screening eligibility using US Preventive Services Task Force guidelines was higher for individuals with income <$15 000 (47.2%) and without a high-school education (46.1%) than individuals with income >$50 000 (16.6%) and with a college degree (13.5%), respectively. Increasing lung cancer screening to 100% compliance was cost-effective ($64 654 per quality-adjusted life-year) and produced economic value by up to $560 per person ($182.1 billion for United States overall). Up to 32.2% of the value was due to reductions in health disparities.

CONCLUSIONS

Significant value in increasing lung cancer screening rates derived from reducing health disparities. Policy makers and clinicians may not be appropriately prioritizing cancer screening if value from reducing health disparities is unconsidered.

Recurrence-Free Survival in Patients With Surgically Resected Non-Small Cell Lung Cancer: A Systematic Literature Review and Meta-Analysis

BACKGROUND

Standard treatment for early-stage or locoregionally advanced non-small cell lung cancer (NSCLC) includes surgical resection. Recurrence after surgery is commonly reported, but a summary estimate for postsurgical recurrence-free survival (RFS) in patients with NSCLC is lacking.

RESEARCH QUESTION

What is the RFS after surgery in patients with stage I-III NSCLC at different time points, and what factors are associated with RFS?

STUDY DESIGN AND METHODS

A systematic search was performed in MEDLINE, EMBASE, and Cochrane databases between January 2011 and June 2021. The primary outcome was RFS at 1, 2, 3, and 5 years postresection. Single-arm, random-effects meta-analyses were done to calculate effect estimates and 95% CIs. Analyses were stratified by stage/substage as per the AJCC Cancer Staging Manual, and RFS was estimated (1) after pooling studies, using seventh or eighth edition staging criteria; and (2) among studies using only the eighth edition. Meta-regressions were performed to assess associations between RFS and patient demographic/clinical characteristics of interest.

RESULTS

Data from 471 studies comprising 1,060 surgical study arms were extracted. RFS estimates from 60,695 patients staged with the seventh or eighth edition were analyzed. RFS ranged from 96% at 1 year postresection to 82% at 5 years for stage I, and from 68% at 1 year to 34% at 5 years for stage III. Estimates for patients staged using only eighth edition criteria were slightly higher. Older age, higher percentage of male patients, advancing stage, larger tumor size, and geographic region (North America/Europe vs Asia) were significantly associated with worse RFS.

INTERPRETATION

This study presents a comprehensive assessment of reported RFS from published clinical literature, offering estimates at multiple postsurgical time points and by geographic region. Findings can inform treatment decisions, clinical trial design, and future research to improve outcomes among patients with NSCLC.

Patient Preferences for Lung Cancer Interception Therapy

Importance

Interception therapy requires individuals to undergo treatment to prevent a future medical event, but little is known about preferences of individuals at high risk for lung cancer and whether they would be interested in this type of treatment.

Objective

To explore preferences of individuals at high risk for lung cancer for potential interception therapies to reduce this risk.

Design, Setting, and Participants

This survey study used a discrete-choice experiment and included hypothetical lung cancer interception treatments with 4 attributes: reduction in lung cancer risk over 3 years, injection site reaction severity, nonfatal serious infection, and death from serious infection. Respondents were assigned to a baseline lung cancer risk of 6%, 10%, or 16% over 3 years. The discrete-choice experiment was administered online (July 13 to September 6, 2022) to US respondents eligible for lung cancer screening according to US Preventive Services Task Force guidelines. Participants included adults aged 50 to 80 years with at least a 20 pack-year smoking history. Statistical analysis was performed from September to December 2022.

Main Outcomes and Measures

Attribute-level preference weights were estimated, and conditional relative attribute importance, maximum acceptable risks, and minimum acceptable benefits were calculated. Characteristics of respondents who always selected no treatment were also explored.

Results

Of the 803 survey respondents, 495 (61.6%) were female, 138 (17.2%) were African American or Black, 55 (6.8%) were Alaska Native, American Indian, or Native American, 44 (5.5%) were Asian or Native Hawaiian or Other Pacific Islander, 104 (13.0%) were Hispanic, Latin American, or Latinx, and 462 (57.5%) were White, Middle Eastern or North African, or a race or ethnicity not listed; and mean (SD) age was 63.0 (7.5) years. Most respondents were willing to accept interception therapy and viewed reduction in lung cancer risk as the most important attribute. Respondents would accept a greater than or equal to a 12.0 percentage point increase in risk of nonfatal serious infection if lung cancer risk was reduced by at least 20.0 percentage points; and a greater than or equal to 1.2 percentage point increase in risk of fatal serious infection if lung cancer risk was reduced by at least 30.0 percentage points. Respondents would require at least a 15.4 (95% CI, 10.6-20.2) percentage point decrease in lung cancer risk to accept a 12.0 percentage point increase in risk of nonfatal serious infection; and at least a 23.1 (95% CI, 16.4-29.8) percentage point decrease in lung cancer risk to accept a 1.2 percentage point increase in risk of death from serious infection. Respondents who were unwilling to accept interception therapy in any question (129 [16.1%]) were more likely to be older and to currently smoke with no prior cessation attempt, and less likely to have been vaccinated against COVID-19 or examined for skin cancer.

Conclusions and Relevance

In this survey study of individuals at high risk of lung cancer, most respondents were willing to consider interception therapy. These results suggest the importance of benefit-risk assessments for future lung cancer interception treatments.

The Effect of Definitions and Cancer Prevalence on Diagnostic Yield Estimates of Bronchoscopy: A Simulation-based Analysis

Rationale: Studies of bronchoscopy have reported diagnostic yield (DY) using different calculation methods, which has hindered comparisons across studies. Objectives: To quantify the effect of the variability of four methods on DY estimates of bronchoscopy. Methods: We performed a simulation-based analysis of patients undergoing bronchoscopy using variations around base case assumptions for cancer prevalence (60%), distribution of nonmalignant findings, and degree of follow-up information at a fixed sensitivity of bronchoscopy for malignancy (80%). We calculated DY, the rate of true positives and true negatives (TNs), using four methods. Method 1 considered malignant and specific benign findings at index bronchoscopy as true positives and TNs, respectively. Method 2 included nonspecific benign findings as TNs. Method 3 considered nonspecific benign findings cases as TNs only if follow-up confirmed benign disease. Method 4 counted all cases with a nonmalignant diagnosis as TNs if follow-up confirmed benign disease. A scenario analysis and probabilistic sensitivity analysis were conducted to demonstrate the effect of parameter estimates on DY. A change in DY of >10% was considered clinically meaningful. Results: Across all pairwise comparisons of the four methods, a DY difference of >10% was observed in 76.7% of cases (45,992 of 60,000 comparisons). Method 4 resulted in DY estimates that were >10% higher than estimates made with other methods in >90% of scenarios. Variation in cancer prevalence had a large effect on DY. Conclusions: Across a wide range of clinical scenarios, the categorization of nonmalignant findings at index bronchoscopy and cancer prevalence had the largest impact on DY. The large variability in DY estimates across the four methods limits the interpretation of bronchoscopy studies and warrants standardization.

A Comparison of Microwave Ablation and Cryoablation for the Treatment of Renal Cell Carcinoma: A Systematic Literature Review and Meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis comparing microwave ablation (MWA) and cryoablation for renal cell carcinoma (RCC).

METHODS

The systematic search was performed in MEDLINE, Embase, and Cochrane databases. Studies published in English from January 2006 to February 2022 that assessed adults with primary RCC who received MWA or cryoablation were included. Study arms from RCTs, comparative observational, and single-arm studies were eligible. The outcomes included local tumor recurrence (LTR), overall survival, disease-free survival, overall/major complications, procedure/ablation time, 1- to 3-month primary technique efficacy, and technical success. Single-arm meta-analyses were performed using the random effects model. Sensitivity analyses excluding low-quality studies assessed using the MINORs scale were performed. Univariable and multivariable examined the effects of prognostic factors.

RESULTS

Baseline characteristics were similar between groups and mean tumor size for MWA and cryoablation were 2.74 and 2.69 cm. Single-arm meta-analyses were similar for LTR and secondary outcomes between cryoablation and MWA. Ablation time was significantly shorter with MWA than with cryoablation (meta-regression weighted mean difference 24.55 minutes, 95% confidence interval -31.71, -17.38, P < .0001). One-year LTR was significantly lower with MWA than cryoablation (odds ratio 0.33, 95% confidence interval 0.10-0.93, P = .04). There were no significant differences for other outcomes.

CONCLUSION

MWA provides significantly improved 1-year LTR and ablation time compared with cryoablation for patients with RCC. Other outcomes appeared similar or favorable for MWA; however, results were not statistically significant. MWA of primary RCC is as safe and effective as cryoablation, which should be confirmed with future comparative studies.

Stereotactic body radiation therapy and thermal ablation for treatment of NSCLC: A systematic literature review and meta-analysis

RATIONALE

Stereotactic body radiation therapy (SBRT) is the standard of care for inoperable early stage non-small cell lung cancer (NSCLC). Use of image guided thermal ablation (IGTA; including microwave ablation [MWA] and radiofrequency ablation [RFA]) has increased in NSCLC, however there are no studies comparing all three.

OBJECTIVE

To compare the efficacy of IGTA (including MWA and RFA) and SBRT for the treatment of NSCLC.

METHODS

Published literature databases were systematically searched for studies assessing MWA, RFA, or SBRT. Local tumor progression (LTP), disease-free survival (DFS), and overall survival (OS) were assessed with single-arm pooled analyses and meta-regressions in NSCLC patients and a stage IA subgroup. Study quality was assessed with a modified methodological index for non-randomized studies (MINORS) tool.

RESULTS

Forty IGTA study-arms (2,691 patients) and 215 SBRT study-arms (54,789 patients) were identified. LTP was lowest after SBRT at one and two years in single-arm pooled analyses (4% and 9% vs. 11% and 18%) and at one year in meta-regressions when compared to IGTA (OR = 0.2, 95%CI = 0.07-0.63). MWA patients had the highest DFS of all treatments in single-arm pooled analyses. In meta-regressions at two and three-years, DFS was significantly lower for RFA compared to MWA (OR = 0.26, 95%CI = 0.12-0.58; OR = 0.33, 95%CI = 0.16-0.66, respectively). OS was similar across modalities, timepoints, and analyses. Older age, male patients, larger tumors, retrospective studies, and non-Asian study region were also predictors of worse clinical outcomes. In high-quality studies (MINORS score ≥ 7), MWA patients had better clinical outcomes than the overall analysis. Stage IA MWA patients had lower LTP, higher OS, and generally lower DFS, compared to the main analysis of all NSCLC patients.

CONCLUSIONS

NSCLC patients had comparable outcomes after SBRT and MWA, which were better than those with RFA.

Diagnostic outcomes of robotic-assisted bronchoscopy for pulmonary lesions in a real-world multicenter community setting

BACKGROUND

Robot-assisted bronchoscopy (RAB) is among the newest bronchoscopic technologies, allowing improved visualization and access for small and hard-to-reach nodules. RAB studies have primarily been conducted at academic centers, limiting the generalizability of results to the broader real-world setting, while variability in diagnostic yield definitions has impaired the validity of cross-study comparisons. The objective of this study was to determine the diagnostic yield and sensitivity for malignancy of RAB in patients with pulmonary lesions in a community setting and explore the impact of different definitions on diagnostic yield estimates.

METHODS

Data were collected retrospectively from medical records of patients ≥ 21 years who underwent bronchoscopy with the Monarch® Platform (Auris Health, Inc., Redwood City, CA) for biopsy of pulmonary lesions at three US community hospitals between January 2019 and March 2020. Diagnostic yield was calculated at the index RAB and using 12-month follow-up data. At index, all malignant and benign (specific and non-specific) diagnoses were considered diagnostic. After 12 months, benign non-specific cases were considered diagnostic only when follow-up data corroborated the benign result. An alternative definition at index classified benign non-specific results as non-diagnostic, while an alternative 12-month definition categorized index non-diagnostic cases as diagnostic if no malignancy was diagnosed during follow-up.

RESULTS

The study included 264 patients. Median lesion size was 19.3 mm, 58.9% were peripherally located, and 30.1% had a bronchus sign. Samples were obtained via Monarch in 99.6% of patients. Pathology led to a malignant diagnosis in 115 patients (43.6%), a benign diagnosis in 110 (41.7%), and 39 (14.8%) non-diagnostic cases. Index diagnostic yield was 85.2% (95% CI: [80.9%, 89.5%]) and the 12-month diagnostic yield was 79.4% (95% CI: [74.4%, 84.3%]). Alternative definitions resulted in diagnostic yield estimates of 58.7% (95% CI: [52.8%, 64.7%]) at index and 89.0% (95% CI: [85.1%, 92.8%]) at 12 months. Sensitivity for malignancy was 79.3% (95% CI: [72.7%, 85.9%]) and cancer prevalence was 58.0% after 12 months.

CONCLUSIONS

RAB demonstrated a high diagnostic yield in the largest study to date, despite representing a real-world community population with a relatively low prevalence of cancer. Alternative definitions had a considerable impact on diagnostic yield estimates.

Machine Learning and Real-World Data to Predict Lung Cancer Risk in Routine Care

BACKGROUND

This study used machine learning to develop a 3-year lung cancer risk prediction model with large real-world data in a mostly younger population.

METHODS

Over 4.7 million individuals, aged 45 to 65 years with no history of any cancer or lung cancer screening, diagnostic, or treatment procedures, with an outpatient visit in 2013 were identified in Optum's de-identified Electronic Health Record (EHR) dataset. A least absolute shrinkage and selection operator model was fit using all available data in the 365 days prior. Temporal validation was assessed with recent data. External validation was assessed with data from Mercy Health Systems EHR and Optum's de-identified Clinformatics Data Mart Database. Racial inequities in model discrimination were assessed with xAUCs.

RESULTS

The model AUC was 0.76. Top predictors included age, smoking, race, ethnicity, and diagnosis of chronic obstructive pulmonary disease. The model identified a high-risk group with lung cancer incidence 9 times the average cohort incidence, representing 10% of patients with lung cancer. Model performed well temporally and externally, while performance was reduced for Asians and Hispanics.

CONCLUSIONS

A high-dimensional model trained using big data identified a subset of patients with high lung cancer risk. The model demonstrated transportability to EHR and claims data, while underscoring the need to assess racial disparities when using machine learning methods.

IMPACT

This internally and externally validated real-world data-based lung cancer prediction model is available on an open-source platform for broad sharing and application. Model integration into an EHR system could minimize physician burden by automating identification of high-risk patients.

Complications After Transthoracic Needle Biopsy of Pulmonary Nodules: A Population-Level Retrospective Cohort Analysis

OBJECTIVE

To provide recent population-based estimates of transthoracic needle biopsy (TTNB) complications and risk factors associated with these complications.

METHODS

This retrospective cohort analysis included adults from a nationally representative longitudinal insurance claims data set who underwent TTNB in 2017 or 2018. Complications that were evaluated included pneumothorax, hemorrhage, and air embolism. Separate logistic regression models estimated the association of pneumothorax or hemorrhage with the setting of care (ie, inpatient or outpatient) and selected baseline patient demographic and clinical characteristics including age, gender, history of chronic obstructive pulmonary disease, diagnosis of pleural effusion, tobacco use, use of oral anticoagulants and antiplatelet agents, prior lung cancer screening, previous bronchoscopy within 1 year, and Elixhauser comorbidity index.

RESULTS

Among 16,971 patients who underwent TTNB, 25.8% experienced a complication within 3 days of the procedure (pneumothorax 23.3%, hemorrhage 3.6%, and air embolism 0.02%). Among patients who experienced pneumothorax, 31.9% required chest tube drainage. Among patients undergoing an outpatient TTNB (n = 12,443), 6.9% were hospitalized within 7 days. Biopsy in an inpatient setting, chronic obstructive pulmonary disease diagnosis, and prior bronchoscopy were associated with higher rates of both pneumothorax and hemorrhage. Prior lung cancer screening was associated with an increased risk of pneumothorax, and prior use of oral anticoagulants or antiplatelets was associated with higher rates of hemorrhage.

CONCLUSION

This contemporary population-based cohort study demonstrated that approximately one-quarter of patients undergoing TTNB experienced a complication. Pneumothorax was the most frequent complication, and hemorrhage and air embolism were rare. Among outpatients, complications from TTNB are an important cause of hospitalization.

Limited duration of antiarrhythmic drug use for newly diagnosed atrial fibrillation in a nationwide population under age 65

INTRODUCTION

Antiarrhythmic drugs (AADs) are commonly used for the treatment of newly diagnosed symptomatic atrial fibrillation (AF), however initial AAD choice, duration of therapy, rates of discontinuation, and factors associated with a durable response to therapy are poorly understood. This study assesses the initial choice and duration of antiarrhythmic drug therapy in the first 2 years after diagnosis of AF in a younger, commercially insured population.

METHODS

A large nationally representative sample of patients age 20-64 was studied using the IBM MarketScan Database. Patients who started an AAD within 90 days of AF diagnosis with continuous enrollment for 1-year pre-index diagnosis and 2 years post-index were included. A Cox proportional hazards model was used to determine factors associated with AAD discontinuation.

RESULTS

Flecainide was used most frequently (26.8%), followed by amiodarone (22.5%), dronedarone (18.3%), sotalol (15.8%), and propafenone (14.0%), with other AADs used less frequently. Twenty-two percent of patients who started on an AAD underwent ablation within 2 years, with 79% discontinuing the AAD after ablation. Ablation was the strongest predictor of AAD discontinuation (hazard ratio [HR], 1.70; 95% confidence interval [CI]: 1.61-1.80), followed by the male gender (HR, 1.10; CI: 1.02-1.19). Older patients (HR, 0.76; CI: 0.72-0.80; reference age 18-49) and those with comorbidities, including cardiomyopathy (HR, 075; CI: 0.61-0.91), diabetes (HR, 0.83; CI: 0.75-0.91), and hypertension (HR, 0.87; CI: 0.81-0.94) were less likely to discontinue AADs.

CONCLUSION

Only 31% of patients remained on the initial AAD at 2 years, with a mean duration of initial therapy 7.6 months before discontinuation.

Improving visual communication of discriminative accuracy for predictive models: the probability threshold plot

Objectives

To propose a visual display-the probability threshold plot (PTP)-that transparently communicates a predictive models' measures of discriminative accuracy along the range of model-based predicted probabilities (Pt).

Materials and Methods

We illustrate the PTP by replicating a previously-published and validated machine learning-based model to predict antihyperglycemic medication cessation within 1-2 years following metabolic surgery. The visual characteristics of the PTPs for each model were compared to receiver operating characteristic (ROC) curves.

Results

A total of 18 887 patients were included for analysis. Whereas during testing each predictive model had nearly identical ROC curves and corresponding area under the curve values (0.672 and 0.673), the visual characteristics of the PTPs revealed substantive between-model differences in sensitivity, specificity, PPV, and NPV across the range of Pt.

Discussion and Conclusions

The PTP provides improved visual display of a predictive model's discriminative accuracy, which can enhance the practical application of predictive models for medical decision making.

Real-world characteristics and readmissions among patients undergoing ablation for ventricular tachycardia: a retrospective database analysis of commercially insured patients in the USA

BACKGROUND

Radiofrequency catheter ablation is an effective treatment to alleviate symptoms and reduce recurrent implantable cardioverter-defibrillator (ICD/CRT-D) shocks in patients with ventricular tachycardia (VT).

OBJECTIVE

To assess the characteristics and outcomes (complications, inpatient readmissions) of commercially insured patients in the USA undergoing ablation for ischaemic or non-ischaemic VT.

METHODS

Patients aged 18-64 years with a primary diagnosis of VT who underwent ablation between 2006 and 2015 were identified using the IBM MarketScan Commercial Database. The rate of complications including vascular complications, pericarditis, pulmonary embolism and pericardial tamponade over a 30-day post-ablation period (including index admission) was examined. Inpatient readmissions (VT-related, heart failure (HF)-related and non-VT arrhythmia-related) over the 12-month post-ablation period were examined. A Cox regression model was used to determine factors associated with inpatient readmissions.

RESULTS

5242 patients (488 with ischaemic and 4754 with non-ischaemic VT) met the study criteria. The majority of VT ablations occurred in an outpatient setting (57% for ischaemic and 66% for non-ischaemic VT). Among complications, vascular complications were most frequent (2.05% among ischaemic and 1.6% among non-ischaemic VT patients) over the 30-day post-ablation period. Among ischaemic VT patients, 17%, 7.6% and 4.7% had VT-related, HF-related and non-VT arrhythmia-related inpatient readmissions, respectively in the 12-month post-ablation period. For non-ischaemic VT patients, these numbers were 7.5%, 1.7% and 3.1%, respectively. Inpatient setting (vs outpatient), baseline ICD/CRT-D implantation, HF comorbidity and ≥2 prior hospitalisations were associated with a higher risk of post-ablation VT-related inpatient readmissions among ischaemic VT patients. Similar factors also were associated with a higher risk of post-ablation VT-related inpatient readmission among non-ischaemic VT patients.

CONCLUSION

Setting of ablation and comorbidity status were found to influence readmission rates. Complication and readmission rates following VT ablation were low indicating towards the favourable safety profile of VT ablation.

Comparison of safety and utilization outcomes in inpatient versus outpatient laparoscopic sleeve gastrectomy: a retrospective, cohort study

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is the most common type of bariatric surgery performed in the United States and may be performed on an outpatient basis. Limited literature exists comparing outcomes of outpatient and inpatient LSG, and study results are conflicting.

OBJECTIVES

To compare safety and utilization outcomes of outpatient versus inpatient LSG.

SETTINGS

Retrospective, multihospital database study (Optum Pan-Therapeutics Database).

METHODS

Patients 18 years of age and older who underwent LSG between October 1, 2015, and December 31, 2018, were identified from the Optum Pan-Therapeutics Database and classified as having undergone outpatient or inpatient surgery. Nearest neighbor propensity score matching and generalized estimating equations accounting for procedural physician-level clustering were used to compare the following outcomes between outpatient and inpatient LSG: all-cause 30-day patient morbidity, hospital readmission, readmission length of stay, bariatric reoperation. and mortality.

RESULTS

We identified 22,945 patients (outpatient: 1542; inpatient: 21,403) meeting the study inclusion criteria. After propensity score matching, the inpatient and outpatient groups contained 1542 and 13,903 patients, respectively. Bariatric reoperation (n = 13) and mortality (n = 5) were rare events occurring in <.1% of all cases. Compared with the inpatient group, the outpatient group had a statistically significant lower readmission length of stay (4.63 versus 3.23 days; P = .0057). Otherwise, there was no significant association between procedure setting and 30-day overall morbidity (4.8% versus 5.3%; P = .5775) or hospital readmission (2.6% versus 2.1%; P = .1841).

CONCLUSIONS

Safety and utilization outcomes were similar between outpatient and inpatient LSG, and outpatient LSG was associated with shorter hospital readmission length of stay.

Real-world outcomes comparison among adults with atrial fibrillation undergoing catheter ablation with a contact force porous tip catheter versus a second-generation cryoballoon catheter: a retrospective analysis of multihospital US database

OBJECTIVE

To compare real-world clinical and economic outcomes among atrial fibrillation (AF) patients undergoing cardiac ablation with the contact force-sensing porous tip THERMOCOOL SMARTTOUCH SF (STSF) catheter versus the Arctic Front Advance Cryoballoon (AFA-CB) catheter.

DESIGN

Retrospective, observational cohort study.

SETTING

Premier Healthcare Database (PHD), between 1 September 2016 and 30 June 2018.

PARTICIPANTS

Patients with AF (≥18 years) were included if they had an index ablation procedure performed using the STSF catheter or AFA-CB catheter at a US hospital that consistently provided inpatient and outpatient data to PHD in the 12-month preindex period. Using 1:1 propensity score matching, patient groups were matched on study covariates.

PRIMARY AND SECONDARY OUTCOME MEASURES

Cost, length of stay (LOS), readmissions, direct current cardioversion (DCCV) and reablation outcomes were compared between matched cohorts of STSF and AFA-CB patients.

RESULTS

A total of 3015 patients with AF met the study criteria, of which 1720 had ablation using the STSF catheter and 1295 had ablation using the AFA-CB catheter. In the propensity-matched sample, patients receiving ablation with the STSF catheter had ~17% lower total costs (US$23 096 vs US$27 682, p≤0.0001) and ~27% lower supply costs (US$10 208 vs US$13 816, p≤0.0001) versus patients receiving ablation with the AFA-CB catheter. A significantly lower likelihood of 4-month to 6-month cardiovascular-related readmission (OR 0.460, 95% CI 0.220 to 0.959) was associated with the STSF catheter versus the AFA-CB catheter. No significant differences in LOS, room and board cost, 4-month to 6-month all-cause and AF-related readmissions, DCCV and reablation were observed among technologies. Sensitivity analysis restricting patient sample by provider ablation volume demonstrated similar results.

CONCLUSION

Lower index ablation total and supply costs were observed among patients with AF undergoing cardiac catheter ablation using the STSF catheter versus the AFA-CB catheter.

Trends and predictors of early ablation for Atrial Fibrillation in a Nationwide population under age 65: a retrospective observational study

BACKGROUND

Catheter ablation (CA) has emerged as an effective treatment for symptomatic atrial fibrillation (AF). However practice patterns and patient factors associated with referral for CA within the first 12 months after diagnosis are poorly characterized. This study examined overall procedural trends and factors predictive of catheter ablation for newly-diagnosed atrial fibrillation in a young, commercially-insured population.

METHODS

A large nationally-representative sample of patients age 20 to 64 from years 2010 to 2016 was studied using the IBM MarketScan® Commercial Database. Patients were included with a new diagnosis of AF in the inpatient or outpatient setting with continuous enrollment for at least 1 year pre and post index visit. Patients were excluded if they had prior history of AF or had filled an anti-arrhythmic drug (AAD) in the pre-index period.

RESULTS

Early CA increased from 5.0% in 2010 to 10.5% in 2016. Patients were less likely to undergo CA if they were located in the Northeast (OR: 0.80, CI: 0.73-0.88) or North Central (OR: 0.91, CI: 0.83-0.99) regions (compared with the West), had higher CHA2DS2-VASc scores, or had Charlson Comorbidity Index (CCI) score of 3 or greater (OR: 0.61; CI: 0.51-0.72).

CONCLUSIONS

CA within 12 months for new-diagnosed AF increased significantly from 2010 to 2016, with most patients still trialed on an AAD prior to CA. Patients are less likely to be referred for early CA if they are located in the Northeast and North Central regions, have more comorbidities, or higher CHA2DS2-VASc scores.

Intracardiac echocardiography use and outcomes after catheter ablation of ventricular tachycardia

Aim: To compare outcomes among patients with implantable cardioverter defibrillator/cardiac resynchronization therapy-defibrillator undergoing outpatient ventricular tachycardia (VT) catheter ablation using intracardiac echocardiography (ICE) versus no ICE. Patients & methods: Patients were classified into ICE (n = 1143)/non-ICE (n = 1677) groups based on ICE procedure codes. Patients in each group were propensity matched on study covariates. Survival analyses were used to assess outcomes. To examine residual confounding, falsification outcomes were evaluated. Results: ICE patients had a 24% lower risk of all-cause readmissions, 24% lower risk of cardiovascular-related and 20% lower risk of VT-related readmissions compared with non-ICE patients. Falsification analyses for ICE use association were nonsignificant. Conclusion: Patients with implantable cardioverter defibrillator/cardiac resynchronization therapy-defibrillator undergoing VT ablation with ICE use had significantly lower likelihood of VT-related readmission.

Real-world outcomes of ventricular tachycardia catheter ablation with versus without intracardiac echocardiography

INTRODUCTION

By providing real-time monitoring of catheter-tissue interface and for complications, intracardiac echocardiography (ICE) during catheter ablation for ventricular tachycardia (VT) may improve outcomes. To test this hypothesis, we compared 12-month readmission rates (all-cause, cardiovascular [CV]-related, and VT-related), repeat ablation, and complications among patients with VT with structural heart disease undergoing ablation with versus without ICE.

METHODS AND RESULTS

Using the 2008-2017 IBM MarketScan Commercial and Medicare Supplemental databases, patients with a history of implantable cardioverter defibrillator/cardiac resynchronization therapy (ICD/CRT-D) who underwent VT ablation with and without ICE use were identified. Propensity matching was performed and regression analysis was used to compare outcomes. After matching, 1324 patients were identified (ICE: 662; non-ICE: 662). The rate of 12-month VT-related readmission (18.13% vs 22.51%; P < .05) and repeat VT ablation (14.35% vs 19.34%; P = .02) postindex discharge were lower among patients in the ICE group compared with the non-ICE group, with a 24% lower risk of 12-month VT-related readmission (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.58-0.99) and a 30% lower risk of repeat ablation (OR, 0.70; 95% CI, 0.52-0.93) vs non-ICE group. The 12-month all-cause (44.56% vs 43.20%; P = .62) and CV-related readmissions (35.20% vs 32.93%; P = 0.38) and complication rates were not significantly different between the two groups.

CONCLUSIONS

VT ablation using ICE was associated with a lower likelihood of 12-month VT-related readmission and repeat ablation compared with non-ICE patients.

Outcomes associated with endovascular treatment among patients with acute ischemic stroke in the USA

BACKGROUND

Few studies have examined the trends in clinical and economic outcomes of patients with acute ischemic stroke (AIS) who receive endovascular therapy (ET) in the real-world setting.

OBJECTIVE

To evaluate characteristics and trends in clinical and economic outcomes among commercially insured patients with AIS undergoing ET between 2011 and 2017.

METHODS

Patients with AIS undergoing ET from January 1, 2011 to June 30, 2017 were identified from administrative claims contained in the IBM MarketScan Commercial and Medicare Supplemental databases. The Mann-Kendall trend test was performed to examine clinical and economic trends.Between 2011 and 2017, 3411 patients (mean age 62.85±15 years) with a primary diagnosis of AIS underwent ET (coverage: Commercial 59%, n=2008; Medicare Supplemental 41%, n=1403). In the Commercial cohort, discharge to home increased significantly (from 29.54% to 39.18%, p<0.05). Length of stay declined significantly among the overall cohort (from 10.96 to 9.05 days, p<0.01) and the Medicare Supplemental cohort (from 10.03 to 8.43 days, p<0.05). All-cause 365-day readmission decreased significantly among the overall cohort (from 47.5% to 36.7%, p<0.05) and the Commercial cohort (from 51.54% to 36.43%, p<0.05) but remained unchanged in the Medicare Supplemental cohort. While index procedure cost did not change significantly ($93 955 to $87 906, p=0.8806), total cost significantly declined in the overall cohort (from $166 922 to $130 678, p<0.05).

CONCLUSIONS

Although with some variation across the samples studied, outcomes including discharge to home, length of stay, readmission, and total cost associated with endovascular stroke therapy seemed to have improved between 2011 and 2017. Index admission cost remained unchanged.

Assessment of obesity prevalence and validity of obesity diagnoses coded in claims data for selected surgical populations: A retrospective, observational study

In many types of surgery, obesity may influence patient selection, prognosis, and/or management. Quantifying the accuracy of the coding of obesity and other prognostic factors is important for the design and interpretation of studies of surgical outcomes based on administrative healthcare data. This study assessed the validity of obesity diagnoses recorded in insurance claims data in selected surgical populations.This was a retrospective, observational study. Deidentified electronic health record (EHR) and linked administrative claims data were obtained for US patients age ≥20 years who underwent a qualifying surgical procedure (bariatric surgery, total knee arthroplasty [TKA], cardiac ablation, or hernia repair) in 2014Q1-2017Q1 (first = index). Patients' body mass index (BMI) as coded in the claims data (error-prone measure) during the index procedure or 180d pre-index was compared with their measured BMI as recorded in the EHR (criterion standard) to estimate the sensitivity and positive predictive value (PPV) of obesity diagnosis codes.Among patients who underwent bariatric surgery (N = 1422), TKA (N = 8670), cardiac ablation (N = 167), or hernia repair (N = 5450), obesity was present in 98%, 63%, 52%, and 54%, respectively, based on measured BMI. PPVs of obesity diagnosis codes were high: 99.3%, 96.0%, 92.8%, and 94.1% in bariatric surgery, TKA, cardiac ablation, and hernia repair, respectively. The sensitivity of obesity diagnoses was: 99.8%, 46.2%, 41.3%, and 42.3% in bariatric surgery, TKA, cardiac ablation, and hernia repair, respectively. Among false-positive patients diagnosed as obese but with measured BMI <30, the proportion with a BMI ≥28 was 40.0%, 67.6%, 60.7%, and 65.8% for bariatric surgery, TKA, cardiac ablation, and hernia repair, respectively.Our data indicate that obesity is highly prevalent in many surgical populations, obesity diagnosis codes have high PPVs, but also obesity is generally undercoded in claims data. Quantifying the validity of diagnosis codes for obesity and other important prognostic factors is important for the design and interpretation of studies of surgical outcomes based on administrative data. Further research is needed to determine the extent to which undercoding of BMI and obesity can be addressed through the use of proxies that may be better documented in claims data.

Association of tumor location with economic outcomes and air leak complications in thoracic lobectomies: results from a national hospital billing dataset

Purpose: To assess whether tumor location during thoracic lobectomies affects economic outcomes or air leak complications.

Patients and methods: Retrospective, observational study using Premier Healthcare Database. The study included patients aged ≥18 years who underwent elective inpatient thoracic lobectomy for lung cancer between 2012 and 2014 (first qualifying=index admission). Three mutually exclusive tumor location groups were formed: upper lobe, middle lobe, and lower lobe. Primary outcomes were index admission’s length of stay (LOS), total hospital costs, and operating room time; in-hospital air leak complications (composite of air leak/pneumothorax) served as an exploratory outcome. Multivariable models were used to examine the association between tumor location and the study outcomes, accounting for covariates and hospital-level clustering.

Results: 8,750 thoracic lobectomies were identified: upper lobe (n=5,284), middle lobe (n=512), and lower lobe (n=2,954). Compared with the upper lobe, the middle and lower lobe groups had statistically significant (p<0.05): shorter adjusted LOS (7.0 days upper vs 5.8 days middle, 6.6 days lower), lower adjusted mean total hospital costs ($26,177 upper vs $23,109 middle, $24,557 lower), and lower adjusted odds of air leak complications (odds ratio middle vs upper=0.81, 95% CI=0.74–0.89; odds ratio lower vs upper=0.60, 95% CI=0.46–0.78). Findings were similar but varied in statistical significance when stratified by open and video-assisted thoracoscopic surgery approach.

Conclusion: Among patients undergoing elective thoracic lobectomy for lung cancer in real-world clinical practice, upper lobe tumors were significantly associated with increased in-hospital resource use and air leak complications as compared with lower or middle lobe tumors.

Using Machine Learning Applied to Real-World Healthcare Data for Predictive Analytics: An Applied Example in Bariatric Surgery

OBJECTIVES

Laparoscopic metabolic surgery (MxS) can lead to remission of type 2 diabetes (T2D); however, treatment response to MxS can be heterogeneous. Here, we demonstrate an open-source predictive analytics platform that applies machine-learning techniques to a common data model; we develop and validate a predictive model of antihyperglycemic medication cessation (validated proxy for A1c control) in patients with treated T2D who underwent MxS.

METHODS

We selected patients meeting the following criteria in 2 large US healthcare claims databases (Truven Health MarketScan Commercial [CCAE]; Optum Clinformatics [Optum]): underwent MxS between January 1, 2007, to October 1, 2013 (first = index); aged ≥18 years; continuous enrollment 180 days pre-index (baseline) to 730 days postindex; baseline T2D diagnosis and treatment. The outcome was no antihyperglycemic medication treatment from 365 to 730 days after MxS. A regularized logistic regression model was trained using the following candidate predictor categories measured at baseline: demographics, conditions, medications, measurements, and procedures. A 75% to 25% split of the CCAE group was used for model training and testing; the Optum group was used for external validation.

RESULTS

13 050 (CCAE) and 3477 (Optum) patients met the study inclusion criteria. Antihyperglycemic medication cessation rates were 72.9% (CCAE) and 70.8% (Optum). The model possessed good internal discriminative accuracy (area under the curve [AUC] = 0.778 [95% CI = 0.761-0.795] in CCAE test set N = 3527) and transportability (external AUC = 0.759 [95% CI = 0.741-0.777] in Optum N = 3477).

CONCLUSION

The application of machine learning techniques to real-world healthcare data can yield useful predictive models to assist patient selection. In future practice, establishment of prerequisite technological infrastructure will be needed to implement such models for real-world decision support.

Abstract WP250: Trends in Outcomes Associated With Thrombectomy Treatment Among Acute Ischemic Stroke Patients: Retrospective Analysis of 2011-2017 Premier Hospital Database

Objectives: Mechanical thrombectomy has become the cornerstone of acute ischemic stroke (AIS) treatment. This study evaluated trends in discharge status, length of stay (LoS), operating room (OR) time, readmissions and costs among AIS patients who underwent mechanical thrombectomy treatment.

Methods: This retrospective cohort study used 2011-2017Q3 Premier Healthcare Database to evaluate discharge status, length of stay (LoS), operating room (OR) time, readmissions, index inpatient costs for AIS patients aged ≥18 years who underwent mechanical thrombectomy. Patients with a diagnosis of AIS in 12-month baseline or with LoS ≤ 1 day were excluded. The Mann-Kendall statistic was used to examine trends in economic and clinical outcomes associated with thrombectomy between 2011 and 2017.

Results: Among 505,824 patients identified with a primary diagnosis of AIS between 2011 and 2017, 11,811 (2.34%) patients were treated with mechanical thrombectomy. The percentage of AIS patients who underwent thrombectomy significantly increased from 1.33% in 2011 to 4.44% in 2017 (p<0.01). The mean age of patients was 66.47 ± 14.75 years, with 51.97% being male. Among AIS patients who underwent thrombectomy, the discharge to home significantly increased from 17.69% in 2011 to 29.64% in 2017 (p< 0.01), while discharge to long-term facility decreased from 53.47% to 49.69% (p=0.10). Mortality rate significantly decreased from 21.60% to 12.64% during the same time period (p< 0.01). The mean OR time declined from 200.73 minutes (2011) to 170.11 minutes (2017) while LoS significantly decreased by 2.95 days (p< 0.01). All-cause 365-day readmission rate decreased from 24.15% in 2011 to 19.78% in 2017 (P=0.35). The index inpatient hospital cost of AIS patients who received thrombectomy significantly declined from $50,516.54 to $42,026.90 (p< 0.01).

Conclusions: The economic and clinical outcomes among AIS patients receiving mechanical thrombectomy treatment improved during the study period. However, the overall burden of stroke among patients who received thrombectomy remains high.

Economic impact of atrial fibrillation ablation with radiofrequency contact force catheter versus cryoballoon catheter

AIM

To compare health utilization among atrial fibrillation (AF) patients undergoing ablation with a contact force-sensing (CF) catheter versus a cryoballoon (CB) catheter.

METHODS

AF patients who underwent ablation using the CF catheter (THERMOCOOL SMARTTOUCH^® catheter) or CB catheter (Arctic Front™/Arctic Front Advance™ catheter) were identified from the Premier Healthcare database. Propensity score analyses were used to evaluate cost, length of stay and readmissions.

RESULTS

The CF catheter (n = 1409) was associated with significantly lower total (∼7%) and supply (∼13%) costs and a significantly lower likelihood of 4-12 month all-cause and CV-related readmission compared with the CB catheter (n = 2306).

CONCLUSION

Differential health utilization outcomes are associated with the CF catheter versus the CB catheter in AF ablation.

Resource use and clinical outcomes in patients with atrial fibrillation with ablation versus antiarrhythmic drug treatment

BACKGROUND

The objective of our study was to compare resource use and clinical outcomes among atrial fibrillation (AF) patients who underwent catheter ablation versus antiarrhythmic drug (AAD) treatment.

METHODS

A retrospective cohort design using the Clinical Practice Research Data-Hospital Episode Statistics linkage data from England (2008-2013) was used. Patients undergoing catheter ablation treatment for AF were indexed to the date of first procedure. AAD patients with at least two different AAD drugs were indexed to the first fill of the second AAD. Patients were matched using 1:1 propensity matching. Primary endpoints including inpatient and outpatient visits were compared between ablation and AAD cohorts in the 4 months-1 year period after index. Secondary endpoints including heart failure, stroke, cardioversion, mortality, and a composite outcome were compared for the 4 months-3 years post-index period in the two groups. Cox-proportional hazards models were estimated for clinical outcomes comparison.

RESULTS

A total of 558 patients were matched in the two groups for resource utilization comparison. The average number of cardiovascular (CV)-related outpatient visits in the 4-12 months post-index period were significantly lower in the ablation group versus the AAD group (1.76 vs 3.57, p < .0001). There was no significant difference in all-cause and CV-related inpatient visits and all-cause outpatient visits among the two groups. For secondary endpoints comparison, 615 matched patients in each group emerged. Ablation patients had 38% lower risk of heart failure (hazard ratio [HR] 0.62, p = 0.0318), 50% lower risk of mortality (HR 0.50, p = 0.0082), and 43% lower risk of experiencing a composite outcome (HR 0.57, p = 0.0009) as compared to AAD treatment cohort.

CONCLUSION

AF ablation was associated with significantly lower CV-related outpatient visits, and lower risk of heart failure and mortality versus AAD therapy.

Comparison of real-world clinical and economic outcomes between the ThermoCool^&reg; SF and ThermoCool^&reg; catheters in patients undergoing radiofrequency catheter ablation for atrial fibrillation

Introduction

This study evaluated the real-world clinical and economic outcomes associated with the use of the ThermoCool^® Surround Flow (SF) and ThermoCool^® catheters in atrial fibrillation (AF) ablation.

Methods

Adults with AF who underwent catheter ablation between January 1, 2013, and December 31, 2016, in a hospital outpatient setting were identified from the Premier Healthcare Database. Using a search strategy of hospital-charge descriptors, patients were classified into two mutually exclusive groups: ThermoCool^® SF catheter and ThermoCool^® catheter. A generalized estimating equation was used to compare index admission cost. Survey logistic regression was used to compare the incidence of inpatient readmission, direct-current cardioversion (DCCV), and repeat ablation. Multivariable analyses were adjusted for hospital clustering and demographic, procedural, hospital, and comorbidity characteristics.

Results

There were 1,014 and 463 patients in the ThermoCool^® SF and ThermoCool^® groups, respectively. The ThermoCool^® SF group had significantly lower odds of all-cause (odds ratio [OR] 0.45; 95% CI 0.27–0.76) and cardiovascular-related readmissions (OR 0.45; 95% CI 0.21–0.96), and DCCV (OR 0.61; 95% CI 0.42–0.88) than the ThermoCool^® group. In patients susceptible to fluid overload, the ThermoCool^® SF group had significantly lower odds of 12-month all-cause (OR 0.42; 95% CI 0.23–0.75), cardiovascular-related (OR 0.31; 95% CI 0.10–0.92), and AF-related readmissions (OR 0.18; 95% CI 0.04–0.80), and DCCV (OR 0.52; 95% CI 0.31–0.87) than the ThermoCool^® group.

Conclusions

Using the ThermoCool^® SF catheter for AF ablation was significantly associated with improved clinical outcomes compared with the ThermoCool^® catheter.

Validation of body mass index (BMI)-related ICD-9-CM and ICD-10-CM administrative diagnosis codes recorded in US claims data

PURPOSE

To quantify the sensitivity and positive predictive value (PPV) of body mass index (BMI)-related ICD-9-CM and ICD-10-CM diagnosis codes in claims data.

METHODS

De-identified electronic health record (EHR) and claims data were obtained from the Optum Integrated Claims-Clinical Database for cross-sections of commercial and Medicare Advantage health plan members age ≥ 20 years in 2013, 2014, and 2016. In each calendar year, health plan members' BMI as coded in the insurance claims data (error-prone measure) was compared with their BMI as recorded in the EHR (gold standard) to estimate the sensitivity and PPV of BMI-related ICD-9-CM and ICD-10-CM diagnosis codes. The unit of analysis was the person-year.

RESULTS

The study sample included 746 763 distinct health plan members who contributed 1 116 283 eligible person-years (median age 56 years; 57% female; 65% commercially insured and 35% with Medicare Advantage). BMI-related diagnoses were coded for 14.6%. The sensitivity of BMI-related diagnoses codes for the detection of underweight, normal weight, overweight, and obesity was 10.1%, 3.7%, 6.0%, and 25.2%, and the PPV was 49.0% for underweight, 89.6% for normal weight, 73.4% for overweight, and 92.4% for obesity, respectively. The sensitivity of BMI-related diagnosis codes was higher in the ICD-10-CM era relative to the ICD-9-CM era.

CONCLUSIONS

The PPV of BMI-related diagnosis codes for normal weight, overweight, and obesity was high (>70%) but the sensitivity was low (<30%). BMI-related diagnoses were more likely to be coded in patients with class II or III obesity (BMI ≥35 kg/m² ), and in 2016 relative to 2013 or 2014.

Comparative Analysis of Hospital Length of Stay and Discharge Status of Two Contemporary Primary Total Knee Systems

This study compares the differences in hospital length of stay (LOS), operating room time (ORT), discharge status, and total hospital costs among primary total knee arthroplasty (TKA) patients implanted with one of two contemporary primary total knee systems. A retrospective cohort analysis of elective inpatient, primary, unilateral TKA patients in the United States from 2013 to 2014 was conducted using the Premier Perspective^® hospital billing database. The included patients had a diagnosis for osteoarthritis and received an ATTUNE^® Knee (Gradually Reducing Radius Knee) or Triathlon™ (Single Radius Knee) from a hospital where both devices were used. Patient, provider, and procedure characteristics were included in generalized estimating equation (GEE) models to explore the impact of device on LOS, ORT, discharge status, and costs accounting for clustering within hospitals. A 1:1 propensity score-matched sensitivity analysis was also conducted. There were 1,178 patients who received gradually reducing radius knee and 5,707 patients who received single radius knee. GEE models indicated that the adjusted mean LOS and ORT for patients who received gradually reducing radius knee were significantly shorter than those who received single radius knee (p < 0.001). The adjusted odds ratios for gradually reducing radius knee patients being discharged to a skilled nursing facility (SNF) or other facility were 39% lower than that for single radius knee patients (odds ratio = 0.61; 95% confidence interval: 0.50-0.75; p < 0.001). The adjusted mean costs for gradually reducing radius knee patients were significantly lower than the single radius knee patients ($12,824 [1,813] vs. $18,713 [1,505]; p < 0.01). Findings were similar in the propensity-matched cohort of 2,044 patients, which was balanced on baseline covariates between devices (standardized differences were ≤ 8%). Patients who received gradually reducing radius knee had a shorter LOS and ORT, were less likely to be discharged to a SNF or other facility, and had lower total hospital cost than those who received single radius knee. These outcomes are increasingly relevant as hospitals bear the financial burden for episodes of care, and will require optimization to achieve success under the Centers for Medicare and Medicaid Services' Comprehensive Care for Joint Replacement model.

Use of the THERMOCOOL SMARTTOUCH catheter for ablation of atrial fibrillation: the relationship between hospital procedure volume, re-admissions, and economic outcomes

OBJECTIVE

The purpose of this study was to examine the relationship between hospital volume of prior THERMOCOOL SMARTTOUCH catheter use and health and economic outcomes among hospitalized patients with atrial fibrillation (AF) undergoing ablation using this device.

MATERIALS AND METHODS

Patients aged ≥18 years with a primary diagnosis of AF undergoing ablation treatment using the THERMOCOOL SMARTTOUCH catheter between January 2014 and June 2016 were identified from the Premier hospital database with the first date of such a procedure being defined as the index date. Hospital volume of prior THERMOCOOL SMARTTOUCH catheter use was determined during the 12-month pre-index period, and was classified into five groups: no volume (0), low volume (1-50), mid volume (51-100), high volume (101-150), and very high volume (≥151). Outcomes, including length of stay (LOS; for inpatient procedure only), hospital costs (total, hospital pharmacy, supply), and all-cause re-admission were evaluated. A generalized estimating equation (GEE) with exchangeable correlation structure was used to examine the impact of hospital volume on LOS, hospital costs, and re-admissions controlling for hospital clustering and other covariates.

RESULTS

The study population included 640 hospitalized AF patients. The adjusted mean LOS was significantly shorter in very high-volume hospitals than hospitals with no volume (mean LOS 2.30 vs 4.33 days; p = .0377). As volume increased, the mean adjusted supply cost tended to decrease, although these changes emerged as non-significant. The 12-month all-cause re-admission was significantly lower among patients undergoing ablation in low (Odds ratio [OR] = 0.27; confidence interval [CI] = 0.08-0.85) and mid (OR = 0.12; CI = 0.02-0.61) volume hospitals compared to hospitals with no volume.

LIMITATIONS

Study results may not be generalizable to all US hospitals.

CONCLUSIONS

Among AF patients undergoing ablation, increased hospital volume of prior THERMOCOOL SMARTTOUCH catheter use was associated with shorter LOS and a lower likelihood of all-cause re-admission.

Economic burden of cancer among patients with surgical resections of the lung, rectum, liver and uterus: results from a US hospital database claims analysis

OBJECTIVES

To determine hospital resource utilization, associated costs and the risk of complications during hospitalization for four types of surgical resections and to estimate the incremental burden among patients with cancer compared to those without cancer.

METHODS

Patients (≥18 years old) were identified from the Premier Research Database of US hospitals if they had any of the following types of elective surgical resections between 1/2008 and 12/2014: lung lobectomy, lower anterior resection of the rectum (LAR), liver wedge resection, or total hysterectomy. Cancer status was determined based on ICD-9-CM diagnosis codes. Operating room time (ORT), length of stay (LOS), and total hospital costs, as well as frequency of bleeding and infections during hospitalization were evaluated. The impact of cancer status on outcomes (from a hospital perspective) was evaluated using multivariable generalized estimating equation models; analyses were conducted separately for each resection type.

RESULTS

Among the identified patients who underwent surgical resection, 23 858 (87.9% with cancer) underwent lung lobectomy, 13 522 (63.8% with cancer) underwent LAR, 2916 (30.0% with cancer) underwent liver wedge resection and 225 075 (11.3% with cancer) underwent total hysterectomy. After adjusting for patient, procedural, and hospital characteristics, mean ORT, LOS, and hospital cost were statistically higher by 3.2%, 8.2%, and 9.2%, respectively for patients with cancer vs. no cancer who underwent lung lobectomy; statistically higher by 6.9%, 9.4%, and 9.6%, respectively for patients with cancer vs. no cancer who underwent LAR; statistically higher by 4.9%, 14.8%, and 15.7%, respectively for patients with cancer vs. no cancer who underwent liver wedge resection; and statistically higher by 16.0%, 27.4%, and 31.3%, respectively for patients with cancer vs. no cancer who underwent total hysterectomy. Among patients who underwent each type of resection, risks for bleeding and infection were generally higher among patients with cancer as compared to those without cancer.

CONCLUSIONS

In this analysis, we found that patients who underwent lung lobectomy, lower anterior resection of the rectum (LAR), liver wedge resection or total hysterectomy for a cancer indication have significantly increased hospital resource utilization compared to these same surgeries for benign indications.

Economic Impact of Laparoscopic Conversion to Open in Left Colon Resections

BACKGROUND AND OBJECTIVES

Studies have shown economic and clinical advantages of laparoscopic left-colon resections. Laparoscopic conversion to open is an important surgical outcome. We estimated conversion incidence, identified risk factors, and measured the clinical and economic impact.

METHODS

In this retrospective study, we used the Premier Perspective database to analyze left-sided colectomies from 2009 to 2014. Operating room time (ORT), length of stay (LOS), total hospital cost (2014 U.S. dollars); along with incidence of in-hospital clinical outcomes (anastomotic leak surrogate [Leak], transfusion, and mortality) were evaluated. Multivariable models accounting for hospital clustering were used to identify conversion risk factors and analyze the effect of conversion on economic and clinical outcomes.

RESULTS

A total of 41,417 patients: 8,468 left hemicolectomy and 32,949 sigmoidectomy were identified. Lap-Conversion incidence was 13.3% (95% CI, 12.9-13.7). Adjusted mean LOS (±SE) days was significantly lower for the Lap-Successful group (4.9 compared with Lap-Conversion 6.8 and Open-Planned 7.0), but Lap-Conversion and Open-Planned had similar LOS. Adjusted mean cost was higher for Lap-Conversion $20,165 compared to Open-Planned $18,797; but this difference was smaller than the cost savings for Lap-Successful $16,206 ± $219. Open-Planned had lower odds of Leak compared to Lap-Conversion. Open-Planned and Lap-Conversion had similar odds of transfusion and mortality. Conversion risk factors included inflammatory bowel disease and left-hemicolectomy. Colorectal specialists were associated with 38% decreased odds of conversion.

CONCLUSIONS

Successful laparoscopic surgery was the most cost effective, with decreased LOS and odds of blood transfusion, leak surrogate, and mortality. Conversion was the most expensive and had increased odds of leak surrogate, but similar LOS compared to Open-Planned. The beneficial effect size of successful laparoscopic surgery was larger than the negative effect of conversion compared to Open-Planned.

Burden of air leak complications in thoracic surgery estimated using a national hospital billing database

Background

One of the most common outcomes of lung resections are parenchymal air leaks. These air leaks are most often self-limited and spontaneously resolve several days after surgery. Historically, only prolonged air leaks have been considered to have a significant effect on patient outcomes. This study aims to evaluate the impact of any air leak complications (aALCs) on resource utilization and mortality.

Methods

The Premier Perspective^® database was used to identify all elective primary lobectomy, segmentectomy, and wedge resections performed from 2012 to 2014; aALC was defined as a composite of air leak and pneumothorax. Generalized estimating equation models were used to estimate the impact of aALCs on length of stay (LOS), operating room time (ORT), hospital costs, and mortality during index hospitalization.

Results

A total of 21,150 patients undergoing lung resection surgery were included in the analysis: lobectomy (n=10,946), segmentectomy (n=1,788), and wedge resection (n=8,416). The overall incidence of aALCs was 24.26% (95% CI [23.68, 24.83]). Identified risk factors included resection type, surgical approach, male gender, and presence of COPD. Patients with aALCs had a significantly higher economic burden (adjusted mean [standard error of mean, SE]: LOS=7.24 [SE=0.12] days; ORT=214.9 [SE=6.4] min; and hospital costs=$26,070 [SE=$1404]) compared to those without aALCs (adjusted mean [SE]: LOS=4.75 [SE=0.07] days; ORT=201.7 [SE=3.9] min; and hospital costs=$19,558 [SE=$399]). aALC was also associated with increased overall index hospitalization mortality (odds ratio=1.90, 95% CI [1.42, 2.55]).

Conclusion

This analysis showed that aALCs are not only frequent but also associated with significantly higher resource utilization and mortality.

The relationship between adherence and total spending among Medicare beneficiaries with type 2 diabetes

OBJECTIVES

This study examined the relationship between medication adherence, cost sharing measured as out-of-pocket spending, and total annual spending in Medicare beneficiaries with type 2 diabetes (T2D) to evaluate whether pharmacy cost-sharing programs have the potential to decrease adherence. These programs may unintentionally increase the risk of medical complications and may result in higher spending overall.

STUDY DESIGN

This retrospective study used 2006 to 2009 Medicare claims data. The sample included patients 65 years or older with T2D (at least 1 claim with International Classification of Diseases, 9th Revision, Clinical Modification codes 250.x0 and 250.x2 and at least 1 antidiabetes drug claim).

METHODS

Medication adherence was measured as proportion of days covered over the first 12 months of observation. Spending and adherence outcomes were defined in deciles.

RESULTS

The sample included 12,305 patient-year observations. Pharmacy spending for patients in the most adherent (10th) decile was 59% higher than that for patients in the least adherent (1st) decile ($4839 vs $3046). Yet, patients in the 10th decile had 49% lower total ($12,531 vs $24,468) and 64% lower medical spending ($7692 vs $21,421) than patients in the 1st decile. Greater out-of-pocket spending was correlated with lower adherence and higher total and medical spending.

CONCLUSIONS

This study describes a widespread variation in medication adherence, pharmacy cost sharing, and medical spending in a sample of Medicare beneficiaries with T2D. We found that lower adherence was correlated with higher cost sharing in the Medicare population, perhaps because of unobserved confounding factors. However, the existing literature on patients with employer-sponsored insurance suggests some of this correlation may be indicative of causal relationships.

Comparison of economic and clinical outcomes between patients undergoing laparoscopic bariatric surgery with powered versus manual endoscopic surgical staplers

AIMS

To compare economic and clinical outcomes between patients undergoing laparoscopic Roux-en-Y gastric bypass (LRY) or laparoscopic sleeve gastrectomy (LSG) with use of powered vs manual endoscopic surgical staplers.

MATERIALS AND METHODS

Patients (aged ≥21 years) who underwent LRY or LSG during a hospital admission (January 1, 2012-September 30, 2015) were identified from the Premier Perspective Hospital Database. Use of powered vs manual staplers was identified from hospital administrative billing records. Multivariable analyses were used to compare the following outcomes between the powered and manual stapler groups, adjusting for patient and hospital characteristics and hospital-level clustering: hospital length of stay (LOS), total hospital costs, medical/surgical supply costs, room and board costs, operating room costs, operating room time, discharge status, bleeding/transfusion during the hospital admission, and 30, 60, and 90-day all-cause readmissions.

RESULTS

The powered and manual stapler groups comprised 9,851 patients (mean age = 44.6 years; 79.3% female) and 21,558 patients (mean age = 45.0 years; 78.0% female), respectively. In the multivariable analyses, adjusted mean hospital LOS was 2.1 days for both the powered and manual stapler groups (p = .981). Adjusted mean total hospital costs ($12,415 vs $13,547, p = .003), adjusted mean supply costs ($4,629 vs $5,217, p = .011), and adjusted mean operating room costs ($4,126 vs $4,413, p = .009) were significantly lower in the powered vs manual stapler group. The adjusted rate of bleeding and/or transfusion during the hospital admission (2.46% vs 3.22%, p = .025) was significantly lower in the powered vs manual stapler group. The adjusted rates of 30, 60, and 90-day all-cause readmissions were similar between the groups (all p > .05). Sub-analysis by manufacturer showed similar results.

LIMITATIONS

This observational study cannot establish causal linkages.

CONCLUSIONS

In this analysis of patients who underwent LRY or LSG, the use of powered staplers was associated with better economic outcomes, and a lower rate of bleeding/transfusion vs manual staplers in the real-world setting.

Comparison of charges and resource use associated with saxagliptin and sitagliptin

OBJECTIVES

Saxagliptin and sitagliptin are two commonly used dipeptidyl peptidase-4 (DPP-4) inhibitors. Little is known about their comparative effectiveness in the real world, particularly their impact on cost and resources use. The objective of this study was to analyze charges and resource use associated with saxagliptin and sitagliptin to understand the impact of these DPP-4 inhibitor treatment options in a real-world setting.

METHODS

This was a retrospective, new-user study approved by the Institutional Review Board at the University of Toledo. Data were collected from a US insurance claims dataset (OptumInsight) for patients newly initiating treatment with saxagliptin or sitagliptin between January 1, 2010 and December 31, 2011. ICD-9 code 250 was used to identify patients with T2D. Overall and diabetes-related medical and pharmacy charges were observed. Inpatient hospitalizations were also compared. Propensity score matching was used to balance the cohorts of patients prescribed saxagliptin and sitagliptin. Appropriate univariate statistical tests were applied to the propensity-matched sample to examine differences in resource utilization outcomes. Statistical significance was evaluated at P < 0.05.

RESULT

After the propensity score matching, each cohort included 7711 patients. Saxagliptin treatment was associated with lower overall charges ($13,292 vs $14,032; P = 0.0023) and overall medical charges ($9,540 vs $10,296; P = 0.0024) during the 6-month follow-up period compared with sitagliptin treatment. No significant differences were observed in the overall pharmacy charges ($3,751 vs $3,753; P = 0.6937) and the diabetes-related charges ($5,141 vs $5,232; P = 0.2957). All-cause and diabetes-related inpatient hospitalization rates were significantly lower with saxagliptin treatment (p = 0.0001 and p = 0.0019, respectively). All-caused inpatient charges were also significantly lower with saxagliptin ($2,917.26 vs $3445.89; P < 0.0001).

CONCLUSION

Compared with patients initiating sitagliptin treatment, patients initiating saxagliptin treatment reported lower overall and medical charges and lower overall and diabetes-related hospitalization rates. These findings may aid payers in managing patients with T2D.

The Impact of Not on Tobacco on Teen Smoking Cessation

This review summarizes end-of-program quit rates from 6 controlled and 10 field-based Not on Tobacco (NOT) evaluations. Approximately 6,130 youth from 5 states and 489 schools participated. Intent-to-treat and compliant quit rates were calculated at 3 months postbaseline (end-of-program). Results from controlled evaluations revealed an aggregate quit rate of 15% and 19%, respectively. The field-based evaluations revealed an aggregate quit rate of 27% and 31%, respectively. NOT youth were two times more likely to quit than comparison youth (OR = 1.94; p = .002; 95% CI 1.267-2.966). This is the first multiyear, multisite review of a teen smoking cessation program reported in the literature and the first longitudinal review of NOT. NOT participants showed consistent, significant positive smoking behavior change across evaluations.

Association Between Hospitalization for Heart Failure and Dipeptidyl Peptidase 4 Inhibitors in Patients With Type 2 Diabetes: An Observational Study

OBJECTIVE

To examine, among patients with type 2 diabetes, the association between hospitalization for heart failure (hHF) and treatment with dipeptidyl peptidase 4 inhibitors (DPP-4is) versus sulfonylureas (SUs), and treatment with saxagliptin versus sitagliptin.

RESEARCH DESIGN AND METHODS

This was a retrospective, observational study using a U.S. insurance claims database. Patients initiated treatment between 1 August 2010 and 30 August 2013, and had no use of the comparator treatments in the prior 12 months (baseline). Each comparison consisted of patients matched 1:1 on a propensity score. Time to each outcome was compared between matched groups using Cox models. Analyses were stratified by the presence of baseline cardiovascular disease (CVD). Secondary analyses examined associations between comparator treatments and other selected cardiovascular events.

RESULTS

After matching, the study included 218,556 patients in comparisons of DPP-4i and SU, and 112,888 in comparisons of saxagliptin and sitagliptin. The hazard ratios (HRs) of hHF were as follows: DPP-4i versus SU (reference): HR 0.95 (95% CI 0.78-1.15), P = 0.580 for patients with baseline CVD; HR 0.59 (95% CI 0.38-0.89), P = 0.013 for patients without baseline CVD; saxagliptin versus sitagliptin (reference): HR 0.95 (95% CI 0.70-1.28), P = 0.712 for patients with baseline CVD; HR 0.99 (95% CI 0.56-1.75), P = 0.972 for patients without baseline CVD. Comparisons of the individual secondary and composite cardiovascular outcomes followed a similar pattern.

CONCLUSIONS

In patients with type 2 diabetes, there was no association between hHF, or other selected cardiovascular outcomes, and treatment with a DPP-4i relative to SU or treatment with saxagliptin relative to sitagliptin.

Understanding CKD among patients with T2DM: prevalence, temporal trends, and treatment patterns-NHANES 2007-2012

OBJECTIVE

To describe the estimated prevalence and temporal trends of chronic kidney disease (CKD) treatment patterns, and the association between CKD and potential factors for type 2 diabetes mellitus (T2DM) in different demographic subgroups.

RESEARCH DESIGN AND METHODS

This was a cross-sectional analysis of adults with T2DM based on multiple US National Health and Nutrition Examination Survey (NHANES) datasets developed during 2007-2012. CKD severity was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 guidelines using the CKD Epidemiology Collaboration (CKD-EPI) equation: mild to moderate=stages 1-3a; moderate to kidney failure=stages 3b-5. Multivariable logistic regression analyses were performed to assess the associations between CKD and potential factors.

RESULTS

Of the adult individuals with T2DM (n=2006), age-adjusted CKD prevalence was 38.3% during 2007-2012; 77.5% were mild-to-moderate CKD. The overall age-adjusted prevalence of CKD was 40.2% in 2007-2008, 36.9% in 2009-2010, and 37.6% in 2011-2012. The prevalence of CKD in T2DM was 58.7% in patients aged ≥65 years, 25.7% in patients aged <65 years, 43.5% in African-Americans and Mexican-Americans, and 38.7% in non-Hispanic whites. The use of antidiabetes and antihypertensive medications generally followed treatment guideline recommendations. Older age, higher hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and having hypertension were significantly associated with CKD presence but not increasing severity of CKD.

CONCLUSIONS

CKD continued to be prevalent in the T2DM population; prevalence remained fairly consistent over time, suggesting that current efforts to prevent CKD could be improved overall, especially by monitoring certain populations more closely.

Healthcare Costs Among Adults with Type 2 Diabetes Initiating DPP-4 Inhibitors

INTRODUCTION

Oral antidiabetes medications, including dipeptidyl peptidase-4 inhibitors (DPP-4is) saxagliptin and sitagliptin, are used for the treatment of type 2 diabetes (T2D). The study objective was to compare all-cause and diabetes-related costs following initiation of saxagliptin or sitagliptin.

METHODS

Patients aged ≥ 18 years initiating saxagliptin or sitagliptin between January 1, 2009 and January 31, 2012 in the Truven Health MarketScan Commercial and Medicare Supplemental databases were identified. Patients were required to have continuous enrollment for ≥ 365 days before and ≥ 365 days after the index date (date of the first saxagliptin or sitagliptin claim). Additionally, patients were required to have a claim with a T2D diagnosis (ICD-9-CM 250.×0, 250.×2) and no claims for a DPP-4i medication before the index date. All-cause and diabetes-related medical costs and total costs (including pharmacy costs) were captured over the 1-year follow-up period. Generalized linear models with log link and gamma distribution were fit to compare costs between the two cohorts using cost ratios, controlling for patient baseline characteristics. Recycled prediction methods were used to generate adjusted predicted costs and confidence intervals.

RESULTS

The final sample comprised 3354 saxagliptin initiators and 26,895 sitagliptin initiators. The average age of saxagliptin and sitagliptin initiators was 57 years and just over 50% were males. After adjusting for baseline characteristics, saxagliptin patients had significantly lower average all-cause medical costs (cost ratio = 0.901, P < 0.001; predicted mean costs: $8687 vs. $9646) compared with sitagliptin patients over the 1-year follow-up. Findings were consistent for diabetes-related medical costs (cost ratio = 0.890, P < 0.001; predicted mean costs: $2180 vs. $2450). Total costs were also lower for saxagliptin initiators (cost ratio = 0.950, P = 0.002; predicted mean costs: $13,911 vs. $14,651) over the 1-year follow-up period.

CONCLUSION

Initiation of treatment with saxagliptin was associated with lower medical costs over 1 year compared with initiation of sitagliptin among adults with T2D.

FUNDING

AstraZeneca.

A discrete-choice experiment to quantify patient preferences for frequency of glucagon-like peptide-1 receptor agonist injections in the treatment of type 2 diabetes

OBJECTIVE

Understanding patients' preferences for attributes of injectable antihyperglycemic regimens may improve patient satisfaction and medication adherence. Our objective was to quantify the preferences of patients with type 2 diabetes mellitus (T2DM) for reducing the frequency of glucagon-like peptide-1 receptor agonist injections from once daily to once weekly.

METHODS

A total of 643 respondents with a self-reported physician diagnosis of type 2 diabetes completed a web-based discrete-choice experiment survey. The sample included four prespecified subgroups: currently using exenatide once weekly (n = 150), liraglutide once daily (n = 153), insulin (but not exenatide once weekly or liraglutide) (n = 156), and no injectable treatment (n = 184). Device attributes included type of injection device, needle size and pain, injection frequency, refrigeration, and injection-site reactions. Random-parameters logit was used to estimate the relative impact of device attributes on treatment choice for each subgroup.

RESULTS

In all subgroups, changing injection frequency from daily to weekly (independent of the effect of injection frequency on preferences for other attributes) was the most important predictor of treatment choice. Switching from a longer and thicker needle to a shorter and thinner needle and eliminating injection-site reactions were also statistically significant predictors of device choice (P < 0.05). Exenatide once weekly users and those not currently using injections were more likely to choose a treatment with characteristics similar to exenatide once weekly.

CONCLUSIONS

The treatment attribute most important to patients choosing among hypothetical injectable treatments for T2DM was injection frequency: patients preferred weekly over daily injections.

LIMITATIONS

The primary limitations of this study are that it included only a limited number of attributes that may not reflect the full complexity of patient choices, diagnosis was self-reported, and patients were recruited from an Internet panel and may not be representative of the T2DM patient population.

Real-world glycemic outcomes in patients with type 2 diabetes initiating exenatide once weekly and liraglutide once daily: a retrospective cohort study

AIM

The glucagon-like peptide-1 receptor agonists exenatide once weekly (QW) and liraglutide once daily (QD) have demonstrated improvements in glycemic outcomes in patients with type 2 diabetes mellitus in randomized clinical trials. However, little is known about their real-world comparative effectiveness. This retrospective cohort study used the Quintiles Electronic Medical Record database to evaluate the 6-month change in glycated hemoglobin (A1C) for patients initiating exenatide QW or liraglutide QD.

METHODS

Patients with type 2 diabetes mellitus prescribed exenatide QW (n=664) or liraglutide QD (n=3,283) between February 1, 2012 and May 31, 2013 were identified. Baseline A1C measures were from 75 days before to 15 days after initiating exenatide QW or liraglutide QD, with follow-up measures documented at 6 months (±45 days). Adjusted linear regression models compared the difference in mean A1C change. A priori defined sensitivity analysis was performed in the subgroup of patients with baseline A1C ≥7.0% and no prescription for insulin during the 12-month pre-index period.

RESULTS

For exenatide QW and liraglutide QD, respectively, mean (SD) age of the main study cohort was 58.01 (10.97) and 58.12 (11.05) years, mean (SD) baseline A1C was 8.4% (1.6) and 8.4% (1.6), and 48.2% and 54.2% of patients were women. In adjusted models, change in A1C did not differ between exenatide QW and liraglutide QD during 6 months of follow-up. Results were consistent in the subgroup analyses.

CONCLUSION

In a real-world setting, A1C similarly improves in patients initiating exenatide QW or liraglutide QD.

Prevalence of pre-existing risk factors for adverse events associated with atypical antipsychotics among commercially insured and medicaid insured patients newly initiating atypical antipsychotics

BACKGROUND

Atypical antipsychotics (AA) differ from one another in their adverse event (AE) profiles. Patient-specific pre-existing risk factors for AEs, including comorbidities and concomitant medications, may render the use of certain AAs potentially inappropriate, and others relatively safer or more tolerable.

OBJECTIVE

To quantify the prevalence of pre-existing risk factors for AEs and potential drug-drug interactions (DDIs) associated with AA treatment among patients with schizophrenia (SCZ), bipolar disorder (BD), or major depressive disorder (MDD) newly-initiating AA treatment.

METHODS

Retrospective, observational study using US claims databases. Patients identified had newly-initiated on a single AA (1/1/2010-11/30/2011; index date), were aged 18-64 years, had insurance enrolment for 12 months pre- (baseline) and 1 month post-index, and had ≥1 medical claim with an ICD-9-CM diagnosis of SCZ, BD, or MDD during baseline. A comprehensive list of AE risk factors, including potential DDIs, was developed based on AA package inserts. Administrative claims-based identification algorithms flagged the presence of each medical risk factor during baseline and identified concomitant prescribing of medications (90 days pre- to 30 days post-index) potentially causing DDIs with AAs.

RESULTS

Of 97,010 patients identified, mean age was 41.2 years and 66.7% were female. Among patients initiating AA treatment, prevalence of pre-existing AE risk factors were aripiprazole 32.2%; olanzapine 51.6%; ziprasidone 75.6%; quetiapine 77.4%; risperidone 82.5%.

CONCLUSION

Despite the availability of several AAs to treat psychiatric conditions, pre-existing AE risk factors can limit patient treatment options. Given inter-AA variability in risk factors, open access to AA may help to optimize appropriate prescribing.

Retrospective study comparing healthcare costs and utilization between commercially insured patients with type 2 diabetes mellitus who are newly initiating exenatide once weekly or liraglutide in the United States

OBJECTIVE

To compare healthcare costs and utilization between commercially insured patients with type 2 diabetes mellitus (T2DM) in the United States newly initiating exenatide once weekly (QW) or liraglutide.

METHODS

This retrospective cohort study used US administrative claims data to study patients with T2DM initiating exenatide QW or liraglutide (initiated therapy = index therapy). Patients were included if they had T2DM, were glucagon-like peptide-1 receptor agonist (GLP-1RA) naïve, initiated exenatide QW or liraglutide from 1 February 2012 to 1 October 2012 (date of initiation = index), were ≥18 years at index, and had continuous enrollment for 12 months before (baseline) to 6 months after index (follow-up). Study outcomes were overall and diabetes-specific healthcare utilization and costs. Multivariable regressions compared the study outcomes between exenatide QW and liraglutide, adjusting for potential confounders. Sensitivity analyses were performed to assess liraglutide by dose (1.2 mg/1.8 mg).

RESULTS

The study sample included 9106 liraglutide (4188, 1.2 mg; 4918, 1.8 mg) patients and 2445 exenatide QW patients. In multivariable-adjusted analyses, compared with liraglutide patients, exenatide QW patients had statistically significantly lower odds of overall inpatient admissions (odds ratio [OR] = 0.80, p = 0.046) and diabetes-specific (OR = 0.83, p = 0.026) inpatient admissions, similar overall total costs ($7833 exenatide QW, $8296 liraglutide, p = 0.069) and diabetes-specific total costs ($3610 exenatide QW, $3736 liraglutide, p = 0.298), and statistically significantly lower overall medical costs ($3939 exenatide QW, $4652 liraglutide, p = 0.008) and diabetes-specific medical costs ($1161 exenatide QW, $1469 liraglutide, p = 0.007). Sensitivity analyses assessing liraglutide by dose were directionally consistent. Unadjusted exploratory analyses showed that exenatide QW patients obtained a greater median number of days supplied for their GLP-1RA during follow-up (141 days) than liraglutide patients (124 days).

CONCLUSIONS

In this 6 month follow-up study, patients receiving exenatide QW had similar total healthcare costs but lower odds of inpatient admission and lower medical costs compared with patients receiving liraglutide.

Cardiovascular event costs in patients with Type 2 diabetes mellitus

OBJECTIVE

To quantify the cost of acute major adverse cardiac events (MACE; myocardial infarction [MI] and stroke) stratified by cardiovascular disease (CVD) risk factors in commercially, Medicare Supplemental-, and Medicaid-insured patients with type 2 diabetes mellitus (T2DM).

METHODS

US administrative claims data were used to identify patients with T2DM aged ≥18 and continuously enrolled with insurance benefits from July 1, 2009-June 30, 2010 (baseline). Patients were classified into three baseline CVD risk groups (highest, medium, and lowest) and followed from July 1, 2010 until 1 year or censoring (follow-up) to measure per-patient per-month (PPPM) all-cause healthcare costs. Multivariable regression compared costs between patients with/without MACE during follow-up. Patients with MACE were further followed for up to 1 year after initial event to quantify longitudinal event costs.

RESULTS

Sample comprised 1,415,598 T2DM patients. Over average follow-up ranging from 301-343 days across CVD risk groups, 10,399 patients experienced MACE. Expected multivariable-adjusted mean PPPM costs of MACE per 100 covered patients within each CVD risk group varied by payer and generally increased with CVD risk (range = $1555 in lowest-risk commercially insured patients to $18,727 in highest-risk Medicaid-insured patients). Longitudinal costs of MACE were lowest among Medicare Supplemental-insured patients with stroke ($22,657 initial event, $2488 PPPM up-to 1-year follow-up care) and highest among Medicaid-insured patients with MI ($41,505 initial event, $4799 PPPM up to 1-year follow-up care).

CONCLUSIONS

These results illustrate the potential clinical and economic importance of considering patients' CVD risk and medications' cardiovascular safety profile when treating T2DM patients.