Demographic and Socioeconomic Characteristics that Impact Selection of Oral Anticoagulants Among Non-Valvular Atrial Fibrillation Patients

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Objectives: Warfarin has been the cornerstone oral anticoagulant for more than 60 years. Since 2008, direct oral anticoagulants (DOACs) have been introduced to the market. In Qatar, dabigatran was introduced in 2011 followed by rivaroxaban in 2014. In this study, we aim to explore the trends in oral anticoagulant use in Qatar over the past 5 years and to what extent did DOACs replace warfarin. We also explored the extent of switching anticoagulation from warfarin to DOACs and vice versa.  Methods: From electronic medical records, we collected all anticoagulant prescriptions dispensed as in- or out-patient from 2011 to 2015 in all Hamad Medical Corporation (HMC) hospitals. For every calendar year, we calculated the number and percentage of patients using each one of the anticoagulants prescribed.  Results: Overall, 7178 patients were using oral anticoagulants over the past 5 years among which 6044(84.2%) used warfarin, 518 (7.2%) used dabigatran and 616 (8.6%) used rivaroxaban. The percentage of patients receiving DOACs increased gradually from approximately 0.5% in 2011 to 26% in 2015. Among patients receiving DOACs, 261 (22.3%) were previous warfarin users, while 188 (16.1%) of DOACs users were switched back to warfarin.  Conclusions: DOACs have been gradually replacing warfarin in Qatar and the trend of their use is similar to that reported in other countries. Warfarin remains the most commonly used oral anticoagulant. PCV87 Bolus Plus Infusion Remains Predominant Mode of GP IIB/IIIA Utilization: A 2015 us Hospital Purchasing Study Mitchell M, Smith C, Werner R The Medicines Company, Parsippany, NJ, USA

Objectives: Platelet glycoprotein IIb/IIIa inhibitors (GPI) are utilized predominantly in patients undergoing percutaneous coronary intervention (PCI); they include the small molecules eptifibatide and tirofiban, and the monoclonal antibody abciximab. Each has bolus and infusion regimens. Clinical trials in product information have 12-24 hour minimum infusion requirements; however, bolus only or shorter infusion regimens have been explored to reduce pharmacy costs. This analysis examines 2015 eptifibatide purchasing to determine the ratio of smaller (bolus) vials to larger (infusion) vials and explore utilization patterns in contemporary hospital practice.  Methods: The Source Healthcare Analytic database was queried for available 2015 months. Eptifibatide data were supplied with 10ML vials and the 100 ML assumed to be bolus and infusion vials respectively. Assuming eptifibatide was used exclusively in PCI patients, the expected ratio of bolus to infusion vials would be 2:2, an estimate based on the recommended dosing regimen of boluses, followed by the minimum 12 hour infusion in an 89 kg patient with normal renal function. Using 2015 wholesale acquisition costs (WAC) of bolus and infusion vials, a 2:2 regimen costs at least $1,336 per patient.  Results: Eptifibatide purchasing through November 2015 was 433,319 vials; 180,158 were bolus (42%) and 253,161 were infusion (58%); a ratio of 2:3. The purchases of infusion vials exceeded the expected ratio of 2:2 in the average PCI patient. Using WAC of bolus and infusion vials, per patient cost of the average regimen is at least $1,845, exceeding the expected $1,336.  Conclusions: 2015 hospital purchasing of eptifibatide suggests that bolus/infusion use predominates. Eptifibatide infusions are common, suggesting adherence to approved dosing with infusions even longer than the minimums recommended. The 2:3 bolus to infusion average regimen costs hospitals $1,845 per patient using 2015 WAC per vial costs. National utilization data provide a framework for individual hospital GPI analyses. PCV88 Demographic and Socioeconomic Characteristics that Impact Selection of Oral Anticoagulants Among Non-Valvular Atrial Fibrillation Patients Keshishian A1, Du J1, Xie L1, Yuce H2, Baser O3 Research, Ann Arbor, MI, USA, 2New York City College of Technology-CUNY and STATinMED Research, New York, NY, USA, 3Columbia University and STATinMED Research, New York, NY, USA

1STATinMED

Objectives: Identify the demographic and socioeconomic predictors associated with non-valvular atrial fibrillation (NVAF) patients that impact initiation of warfarin versus novel oral anticoagulants (NOACs).  Methods: Patients with at least one prescription for warfarin, apixaban, dabigatran, or rivaroxaban were selected from the national Medicare database (01JAN2013-31DEC2013). The first oral anticoagulant (OAC) claim date was defined as the index date. Members were required to be age ≥ 65 years, have an atrial fibrillation diagnosis (International Classification of Diseases, Ninth Revision, Clinical Modification code 427.31) and have continuous health plan enrollment for 6 months pre-index date. Members with evidence of mitral valvular heart disease, valve replacement procedures, pregnancy, or OAC claims pre-index date were excluded. Multinomial logistic regression was used to identify the covariates that were associated with initiation of apixaban, dabigatran, rivaroxaban, or warfarin (reference).  Results: The study included 567 apixaban, 905 dabigatran, 2,443 rivaroxaban, and 7,136 warfarin patients. Patients aged 75-84 and ≥ 85 years were less likely to initiate dabigatran (75-84: odds ratio [OR]: 0.73, 95% confidence interval [CI]: 0.62-0.84; ≥ 85: OR: 0.47, 95% CI: 0.39-0.58) and rivaroxaban (7584: OR: 0.78, 95% CI: 0.70-0.87; ≥ 85: OR: 0.63, 95% CI: 0.55-0.72). Female patients were more likely to initiate rivaroxaban (OR: 1.18; 95% CI: 1.07-1.30) compared to male patients. Patients with a high socioeconomic status (SES) score were more likely to initiate apixaban (OR: 1.36; 95% CI: 1.06-1.73) compared to those with low SES. Additionally, patients with a higher Charlson Comorbidity Index (CCI) score were less likely to initiate apixaban (OR: 0.87; 95% CI: 0.84-0.90), dabigatran (OR: 0.90; 95% CI: 0.87-0.92), and rivaroxaban (OR: 0.93; 95% CI: 0.91-0.96).  Conclusions: Initiation of OACs is dependent on patient demographics and clinical characteristics. Gender, SES score, age, and CCI score are all significant predictors for the initiation of OACs. PCV89 Racial Disparities in Amputation Rates Among Native Americans with Peripheral Artery Disease: Analysis of the Health Care Cost and Utilization Project Database Rizzo JA1, Chen J2, Laurich C3, Santos A3, Martinsen BJ 4, Ryan MP5, Kotlarz H4,

Gunnarsson C5 1Stony Brook University, Stony Brook, NY, USA, 2University of Maryland, College Park, MD, USA, 3Standford Health, Sioux Falls, SD, USA, 4Cardiovascular Systems, Inc., St. Paul, MN, USA, 5CTI Clinical Trial and Consulting Services, Cincinnati, OH, USA

Objectives: While studies have documented disparities in amputation rates for Native American patients with peripheral artery disease (PAD), the importance of specific factors has not been quantified. This study seeks to quantify these factors, and to determine how much of the difference reflects observable versus unexplained characteristics.  Methods: This study used the nationally-representative HCUP inpatient database from 2006-2013 for Native American and Caucasian patients with a primary diagnosis of PAD. Amputation rates were calculated for any leg amputation [above or below-the-knee] and separately for below-the-knee only. Logistic regression models were estimated to identify the determinants of amputation rates for Native Americans compared to Caucasians. All models were adjusted for patient demographics, income strata, comorbidities, PAD risk factors, and hospital characteristics. The Blinder-Oaxaca decomposition method was employed to ascertain and quantify factors that contribute to the differences in amputation rates between Native Americans and Caucasians.  Results: Treatment patterns are dramatically different for Native Americans residing in the West Census Region relative to the other regions. Multivariable results reveal that Native Americans in the West are more than twice as likely to be amputated as are Caucasians. Decomposition results show that observed factors collectively explain just 43-62% of the variation in amputation rates. Individual observed factors contribute little to explaining these disparities. In contrast, results from the other three Census Regions reveal that amputation rates are not statistically different between Native Americans and Caucasians.  Conclusions: Native Americans with PAD who reside in the West Census Region are substantially more likely to be amputated than are Caucasians. Most of this variation appears to reflect differences in treatment patterns that are unrelated to illness severity, demographic factors, hospital characteristics, and other factors. These substantial unexplained disparities may reflect systematic differences in treatment patterns by race. PCV90 Racial Disparities in Amputation Rates for Patients with Peripheral Artery Disease: Long-Term Trends and Projections to 2020 Rizzo JA1, Chen J2, Kotlarz H3, Martinsen BJ 3, Ryan MP4, Palli S4, Gunnarsson C4 1Stony Brook University, Stony Brook, NY, USA, 2University of Maryland, College Park, MD, USA, 3Cardiovascular Systems, Inc , St Paul, MN, USA, 4CTI Clinical Trial and Consulting Services, Cincinnati, OH, USA .

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Objectives: Studies have documented racial disparities in amputation rates for patients with peripheral artery disease (PAD), long-term trends have not been examined, nor have forecasts of future disparities been estimated. This study seeks to provide this information by estimating long-term patterns of racial disparities in amputation rates and projecting future differences through the year 2020.  Methods: This study used the nationally-representative HCUP inpatient database from 2006-2013 for patients with a primary diagnosis of PAD. Amputation rates were calculated for any leg amputation [above or below-the-knee] and separately for below-the-knee only. Logistic regression models were estimated to identify the determinants of amputation rates for African Americans, Hispanics, Asians, Native Americans and Caucasians. All models were adjusted for patient demographics, income strata, comorbidities, PAD risk factors, and hospital characteristics. Using these model estimates, forecasts of amputation rates were generated for each group through the year 2020. Excess annual amputations (EAAs) were calculated as the difference in amputation rates between minorities and Caucasians, multiplied by the number of inpatient visits for minorities with a primary diagnosis of PAD.  Results: While all minorities had higher amputation rates than Caucasians, these rates were substantially greater for African Americans and in some years up to 50% higher. These results persist for African Americans throughout the forecast period. Analysis revealed that African Americans consistently had between 1,200 – 1,800 EAAs per annum, with an average annual EAA of 1,503. Given lifetime amputation-related healthcare costs of $650,000 per patient, this translates into aggregate healthcare costs of $780 million- $1.2 billion.  Conclusions: African Americans have substantially higher amputation rates than other racial and ethnic groups examined, regardless of amputation measure, and a far greater number of excess annual amputations. In the absence of policies aimed at reducing these disparities, such differences are projected to persist through the year 2020. PCV91 Racial Disparities in Amputation Rates for the Treatment of Peripheral Artery Disease Using the Health Care Cost and Utilization Project Database Mustapha 1, Fisher Sr 2, Rizzo JA3, Chen J4, Martinsen BJ5, Kotlarz H5, Ryan MP6, Gunnarsson C6 1Metro Health Hospital, Wyoming, MI, USA, 2The Surgical Clinic, Pllc, Nashville, TN, USA, 3Stony Brook University, Stony Brook, NY, USA, 4University of Maryland, College Park, MD, USA, 5Cardiovascular Systems, Inc., St. Paul, MN, USA, 6CTI Clinical Trial and Consulting Services, Cincinnati, OH, USA .

Objectives: While studies have documented racial and ethnic disparities in amputation rates for patients with peripheral artery disease (PAD), the importance of specific factors has not been quantified. This research seeks to provide such evidence, and to quantify how much of the difference reflects observable versus unexplained factors.  Methods: This study used the nationally-representative HCUP inpatient database from 2006-2013 for patients with a primary diagnosis of PAD. Amputation rates were calculated for major and minor amputations. Logistic regression models were estimated to identify the determinants of amputation rates. All models were adjusted for patient demographics, income strata, comorbidities, risk factors and hospital characteristics. The Blinder-Oaxaca decomposition method was employed to ascertain and quantify the factors that contribute to the racial/ethnic disparities.  Results: Caucasians are generally older, wealthier, have milder disease and