PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection

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  • Article
    Citation - WoS: 27
    Citation - Scopus: 30
    Prevalence of Mastocytosis and Hymenoptera Venom Allergy in the United States
    (Mosby-Elsevier, 2021-11-01) Volertas, Sofija; Akın, Cem; Khokhar, Dilawar; Schuler, Charles F; Chen, Lu; Yüce, Huseyin; Montejo, Jenny M; Başer, Onur
    Background : Mastocytosis is a risk factor for hymenoptera venom anaphylaxis (HVA). Current guidelines recommend measuring tryptase in HVA patients and that those with mastocytosis pursue lifelong venom immunotherapy (VIT). Available data on HVA and mastocytosis largely derives from European single-center studies and the prevalence of HVA with and without mastocytosis in the United States (US) is unknown.Objective : We sought to determine the prevalence of HVA and mastocytosis in the US using an insurance claims database and evaluate the impact of mastocytosis on VIT in HVA patients in a US cohort. Methods :The IBM Watson Database, consisting of insurance claims from approximately 27 million US patients in 2018, was queried to identify patients with HVA and/or mastocytosis. Further, a retrospective study of 161 patients undergoing VIT between 2015 – 2018 at the University of Michigan (U-M) was conducted. Results :In the IBM Watson Database, the prevalence of HVA was 167 per 100,000 (0.167%) and the prevalence of mastocytosis 10 per 100,000 (0.010%) overall and 97 per 100,000 (0.097%) among those with HVA. Mastocytosis showed a 9.7-fold increase among HVA patients versus the general population. In the U-M cohort, 2.6% of VIT patients had mastocytosis. Tryptase level did not correlate with venom reaction severity but was higher in patients with systemic VIT reactions. Conclusions :We observed a lower US HVA prevalence than previously reported. Mastocytosis was more common in US HVA patients, though at lower rates than previously reported. In VIT patients there was no correlation between tryptase level and reaction severity. Key words :Tryptasevenom allergyvenom immunotherapyanaphylaxismastocytosismast cell activation syndromemast cell disease Abbreviations Hymenoptera venom allergyHVAUnited StatesUSVenom immunotherapyVITMast Cell DiseaseMCDAmerican Academy of Allergy, Asthma, and Immunology
  • Article
    Citation - WoS: 44
    Citation - Scopus: 49
    Population Density Index and Its Use for Distribution of Covid-19: a Case Study Using Turkish Data
    (Elsevier, 2021-02-01) Başer, Onur
    Since March 2020, many countries around the world have been experiencing a large outbreak of a novel coronavirus (2019-nCoV). Because there is a higher rate of contact between humans in cities with higher population weighted densities, Covid-19 spreads faster in these areas. In this study, we examined the relationship between population weighted density and the spread of Covid-19. Using data from Turkey, we calculated the elasticity of Covid-19 spread with respect to population weighted density to be 0.67 after controlling for other factors. In addition to the density, the proportion of people over 65, the per capita GDP, and the number of total health care workers in each city positively contributed to the case numbers, while education level and temperature had a negative effect. We suggested a policy measure on how to transfer health care workers from different areas to the areas with a possibility of wide spread.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 15
    Economic Outcomes in Patients With Chemotherapy-Naive Metastatic Castration-Resistant Prostate Cancer Treated With Enzalutamide or Abiraterone Acetate Plus Prednisone
    (Springer, 2020-02-28) Lechpammer, Stanislav; Ramaswamy, Krishnan; Wang, Li; Mardekian, Jack; George, Daniel J.; Sandin, Rickard; Schultz, Neil M.; Başer, Onur; Huang, Ahong
    Introduction: Prostate cancer (PC) is the second leading cause of cancer death among US men and accounts for considerable healthcare expenditures. We evaluated economic outcomes in men with chemotherapy-naı¨ve metastatic castration-resistant PC (mCRPC) treated with enzalutamide or abiraterone acetate plus prednisone (abiraterone). Methods: We performed a retrospective analysis on 3174 men (18 years or older) utilizing the Veterans Health Administration (VHA) database from 1 April 2014 to 31 March 2018. Men with mCRPC were included if they had at least one pharmacy claim for enzalutamide or abiraterone (first claim date = index date) following surgical or medical castration, had no chemotherapy treatment within 12 months prior to the index date, and had continuous VHA enrollment for at least 12 months pre- and post-index date. Men were followed until death, disenrollment, or end of study and were 1:1 propensity score matched (PSM). All-cause and PC-related resource use and costs per patient per month (PPPM) in the 12 months post index were compared between matched cohorts. Results: We identified 1229 men with mCRPC prescribed enzalutamide and 1945 prescribed abiraterone with mean ages of 74 and 73 years, respectively. After PSM, each cohort had 1160 patients. The enzalutamide cohort had fewer all-cause (2.51 vs 2.86; p\0.0001) and PC-related outpatient visits (0.86 vs 1.03; p\0.0001), with corresponding lower all-cause ($2588 vs $3115; p\0.0001) and PC-related ($1356 vs $1775; p\0.0001) PPPM outpatient costs compared with the abiraterone cohort. Allcause total costs (medical and pharmacy) PPPM ($8085 vs $9092; p = 0.0002) and PC-related total costs PPPM ($6321 vs $7280; p\0.0001) were significantly lower in the enzalutamide cohort compared with the abiraterone cohort. Conclusions: Enzalutamide-treated men with chemotherapy-naı ¨ve mCRPC had significantly lower resource utilization and healthcare costs compared with abiraterone-treated men. Plain Language Summary: Plain language summary available for this article.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 12
    Elevated White Blood Cell Levels and Thrombotic Events in Patients With Polycythemia Vera: a Real-World Analysis of Veterans Health Administration Data
    (Elsevier Inc., 2020-02-01) Wang, Li; Parasuraman, Shreekant V.; Sulena Shrestha; Paranagama, Dilan C.; Yu, Jingbo; Scherber, Robyn Marie; Başer, Onur; Shrestha, Sulena
    Background: Patients with polycythemia vera (PV) have a substantial risk of thrombotic events (TEs). The objective of the present analysis was to describe the association between white blood cell (WBC) levels and occurrence of TEs among patients with PV from a large real-world population. Patients and Methods: The present retrospective analysis using Veterans Health Administration claims data (October 1, 2005, to September 30, 2012) evaluated adult patients assigned to 4 WBC count categories (WBC count < 7.0, 7.0-8.4, 8.5 to < 11.0, and ≥ 11.0 × 109/L) to compare the risk of TEs (reference, WBC count, < 7.0 × 109/L group). Analysis was performed using a Cox proportional hazards model, considering WBC status as a time-dependent covariate. Results: Of the 1565 patients with PV included in the present analysis, the WBC count was < 7.0 × 109/L for 428 (27.3%), 7.0 to 8.4 × 109/L for 375 (24.0%), 8.5 to < 11.0 × 109/L for 284 (18.1%), and ≥ 11.0 × 109/L for 478 (30.5%). Of the 1565 patients, 390 (24.9%) had experienced a TE during the study period. The mean follow-up ranged from 3.6 to 4.5 years. Compared with the reference group (WBC count < 7.0 ×109/L), the hazard ratio for TEs was 1.10 (95% confidence interval [CI], 0.82-1.48; P = .5395), 1.47 (95% CI, 1.10-1.96; P = .0097), and 1.87 (95% CI, 1.44-2.43; P < .0001) for patients with a WBC count of 7.0 to 8.4, 8.5 to < 11.0, and ≥ 11.0 ×109/L, respectively. Conclusion: A positive, significant association between an increased WBC count of ≥ 8.5 ×109/L and the occurrence of TEs was observed in patients with PV. The potential thrombogenic role of WBCs in patients with PV supports the continued inclusion of WBC count control in disease management and evaluation of the response to therapy. © 2019 The AuthorsPatients with polycythemia vera (PV) have a substantial risk of thrombotic events (TEs). In the present retrospective analysis using Veterans Health Administration claims data, 25% of 1565 patients experienced a TE during follow-up. We observed a positive, significant association between white blood cell (WBC) counts ≥ 8.5 × 109/L and TE occurrence (reference, WBC count < 7.0 × 109/L), supporting continued inclusion of WBC count control in disease management. © 2019 The Authors
  • Article
    Citation - WoS: 7
    Citation - Scopus: 9
    Hematocrit Levels and Thrombotic Events in Patients With Polycythemia Vera: an Analysis of Veterans Health Administration Data
    (Springer, 2019-09-24) Parasuraman, Shreekant; Robyn Scherber; Jingbo Yu; Li Wang; Dilan Paranagama; Sulena Shrestha; Başer, Onur; Yu, Jingbo; Paranagama, Dilan; Shrestha, Sulena; Scherber, Robyn; Wang, Li
    Patients with polycythemia vera (PV) have a high incidence of thrombotic events (TEs), contributing to a greater mortality risk than the general population. The relationship between hematocrit (HCT) levels and TE occurrence among patients with PV from the Veterans Health Administration (VHA) was evaluated to replicate findings of the CYTO-PV trial with a real-world patient population. This retrospective study used VHA medical record and claims data from the first claim with a PV diagnosis (index) until death, disenrollment, or end of study, collected between October 1, 2005, and September 30, 2012. Patients were aged ? 18 years at index, had ? 2 claims for PV (ICD-9-CM code, 238.4) ? 30 days apart during the identification period, continuous health plan enrollment from 12 months pre-index until end of study, and ? 3 HCT measurements per year during follow-up. This analysis focused on patients with no pre-index TE, and with all HCT values either < 45% or ? 45% during the follow-up period. The difference in TE risk between HCT groups was assessed using unadjusted Cox regression models based on time to first TE. Patients (N = 213) were mean (SD) age 68.9 (11.5) years, 98.6% male, and 61.5% white. TE rates for patients with HCT values < 45% versus ? 45% were 40.3% and 54.2%, respectively. Among patients with ? 1 HCT before TE, TE risk hazard ratio was 1.61 (95% CI, 1.03–2.51; P = 0.036). This analysis of the VHA population further supports effective monitoring and control of HCT levels < 45% to reduce TE risk in patients with PV.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 13
    Risk of Venous Thromboembolism After New Onset Heart Failure
    (Nature Research, 2019-11-22) Smilowitz, Nathaniel R.; Wang, Li; Berger, Jeffrey S.; Zhao, Qi; Shrestha, Sulena; Başer, Onur
    New-onset heart failure (HF) is associated with cardiovascular morbidity and mortality. It is uncertain to what extent HF confers an increased risk of venous thromboembolism (VTE). Adults >= 65 years old hospitalized with a new diagnosis of HF were identified from Medicare claims from 2007-2013. We identified the incidence, predictors and outcomes of VTE in HF. We compared VTE incidence during follow-up after HF hospitalization with a corresponding period 1-year prior to the HF diagnosis. Among 207,535 patients with a new HF diagnosis, the cumulative incidence of VTE was 1.4%, 2.5%, and 10.5% at 30 days, 1 year, and 5 years, respectively. The odds of VTE were greatest immediately after newonset HF and steadily declined over time (OR 2.2 [95% CI 2.0-2.3], OR 1.5 [1.4-1.7], and OR 1.2 [1.2-1.3] at 0-30 days, 4-6 months, and 7-9 months, respectively). Over 26-month follow-up, patients with HF were at two-fold higher risk of VTE than patients without HF (adjusted HR 2.31 [2.18-2.45]). VTE during follow-up was associated with long-term mortality (adjusted HR 1.60, 95% CI 1.56-1.64). In conclusion, patients with HF are at increased risk of VTE early after a new HF diagnosis. VTE in patients with HF is associated with long-term mortality.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Health Outcomes Among Patients Diagnosed With Schizophrenia in the Us Veterans Health Administration Population Who Transitioned From Once-Monthly To Once-Every Paliperidone Palmitate: an Observational Retrospective Analysis
    (Springer, 2019-08-08) Khouyr, Antoine El; Wang, Li; Joshi, Kruti; Patel, Charmi; Başer, Onur; Huang, Ahong; El Khoury, Antoine
    There is limited literature on treatment patterns, healthcare resource utilization (HRU), and costs among patients who transition from once-monthly paliperidone palmitate (PP1M) to once-every-3-month paliperidone palmitate (PP3M) in a real-world setting. Hence, this study compared treatment patterns, HRU, and costs 12-month pre- and post-PP3M transition among Veteran’s Health Administration (VHA) patients with schizophrenia.
  • Article
    Citation - Scopus: 10
    Patterns of Treatment and Correction of Hyponatremia in Intensive Care Unit Patients
    (W.B. Saunders, 2015-10-01) Badawi, Omar; Chiodo, Joseph; Waikar, Sushrut S.; Boklage, Susan; Dasta, Joseph; Xie, Lin; Başer, Onur
    Purpose: The goal of this study was to examine the real-world patterns of care and interventions among intensive care unit (ICU) patients with hypervolemic and euvolemic hyponatremia using a large clinical database. Materials and Methods: The Phillips eICU Research Institute database was used to investigate hyponatremia treatment patterns and trends, mortality, and ICU and hospital length of stay. Demographics, clinical characteristics, and outcome variables were compared in patients corrected for hyponatremia using both a more strict and a less strict definition. Results: At admission, 35%, 55%, and 10% of patients had mild, moderate, and severe hyponatremia, respectively. At the end of an ICU stay, the percentage of patients who did not have corrected serum sodium concentration was 48% (using a more strict definition) and 24% (using a less strict definition). Using either definition of correction, patients with serum sodium correction had lower mortality and longer survival than did patients without corrected serum sodium concentration. Conclusions: A significant proportion of hyponatremia is not corrected during an ICU stay. Critically ill patients with hyponatremia who have their serum sodium corrected have lower mortality and longer survival, highlighting the need for more attention to hyponatremia and its correction in critically ill patients. © 2015 Elsevier Inc.
  • Article
    Citation - Scopus: 24
    Epidemiology and Economic Burden of Serotonin Syndrome With Concomitant Use of Serotonergic Agents: a Retrospective Study Utilizing Two Large Us Claims Databases
    (Physicians Postgraduate Press Inc., 2017-12-28) Alley, Stephanie; Nguyen, Charles T.; McCarron, Robert M.; Wang, Zhixiao; Xie, Lin; Başer, Onur
    Objective: Serotonin syndrome (SS) is an adverse drug reaction occurring among patients receiving serotonergic agents (SAs), and although SAs are commonly prescribed, the epidemiology and economic burden of SS with concomitant SA use have not been comprehensively examined. The objective of this study was to investigate the prevalence, incidence, and economic burden of SS with SA use. Methods: A retrospective cohort study was conducted using Veterans Health Administration (VHA) records (identification period: October 1, 2008-September 30, 2012) and commercially insured patient records (Intercontinental Marketing Services PharMetrics Plus; identification period: January 1, 2010-December 31, 2013). Cohorts were based on drug classification and exposure: single monoamine oxidase inhibitor (MAOI), MAOIs in combination with SAs, single non-MAOI SA, and multiple non-MAOI SAs (2, 3, 4, ? 5). Participants were aged ? 18 years with continuous health plan enrollment for 12 months prior to the first SA claim. Outcomes were SS events (ICD-9-CM: 333.99), annual incidence and prevalence, related health care utilization and costs, and SS incidence relative risk. Results: Over 15 million patients were identified and categorized by SA prescription type. SS incidence in both populations decreased: 0.19%-0.07% (VHA) and 0.17%-0.09% (commercially insured). Overall SS prevalence decreased during the study period. Compared to single non-MAOI SA patients, SS incidence relative risk was highest among patients prescribed ? 5 non-MAOI SAs. Inpatient stays accounted for 4.35% (VHA) and 0.88% (commercially insured) of all SS events. Of SS-related inpatient stays, median costs were $8,765 (VHA) and $10,792 (commercially insured). Conclusions: SS incidence and prevalence and SS-related hospitalization risk among patients prescribed SAs were low in both populations. This study provides additional information regarding SS risk associated with SA use. © 2017, Physicians Postgraduate Press Inc. All rights reserved.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 8
    The Use of Decomposition Methods in Real-World Treatment Benefits Evaluation for Patients With Type 2 Diabetes Initiating Different Injectable Therapies: Findings From the Initiator Study
    (Elsevier Science Inc, 2017-12-01) Ke, Xuehua; Buysman, Erin; Wei, Wenhui; Xie, Lin; Grabner, Michael; Brekke, Lee; Başer, Onur
    Background: Determining characteristics of patients likely to benefit from a particular treatment could help physicians set personalized targets. OBJECTIVES: To use decomposition methodology on real-world data to identify the relative contributions of treatment effects and patients' baseline characteristics. METHODS: Decomposition analyses were performed on data from the Initiation of New Injectable Treatment Introduced after Antidiabetic Therapy with Oral-only Regimens (INITIATOR) study, a real-world study of patients with type 2 diabetes started on insulin glargine (GLA) or liraglutide (LIRA). These analyses investigated relative contributions of differences in baseline characteristics and treatment effects to observed differences in 1-year outcomes for reduction in glycated hemoglobin A1c (HbA1c) and treatment persistence. RESULTS: The greater HbA1c reduction seen with GLA compared with LIRA (-1.39% vs. -0.74%) was primarily due to differences in baseline characteristics (HbA1c and endocrinologist as prescribing physician; P < 0.050). Patients with baseline HbA1c of 9.0% or more or evidence of diagnosis codes related to mental illness achieved greater HbA1c reductions with GLA, whereas patients with baseline polypharmacy (6-10 classes) or hypogylcemia achieved greater reductions with LIRA. Decomposition analyses also showed that the higher persistence seen with GLA (65% vs. 49%) was mainly caused by differences in treatment effects (P < 0.001). Patients 65 years and older, those with HbA1c of 9.0% or more, those taking three oral antidiabetes drugs, and those with polypharmacy of more than 10 classes had higher persistence with GLA; patients 18 to 39 years and those with HbA1c of 7.0% to less than 8.0% had higher persistence with LIRA. CONCLUSIONS: Although decomposition does not demonstrate causal relationships, this method could be useful for examining the source of differences in outcomes between treatments in a real-world setting and could help physicians identify patients likely to respond to a particular treatment. Copyright (C) 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.