PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.11779/1928
Browse
13 results
Search Results
Article Citation - WoS: 6Citation - Scopus: 6Effects of Vaccination and the Spatio-Temporal Diffusion of Covid-19 Incidence in Turkey(John Wiley and Sons Inc, 2022-06-04) Bilgel, Fırat; Karahasan, Burhan CanThis study assesses the spatio-temporal impact of vaccination efforts on Covid-19 incidence growth in Turkey. Incorporating geographical features of SARS-CoV-2 transmission, we adopt a spatial Susceptible–Infected–Recovered (SIR) model that serves as a guide of our empirical specification. Using provincial weekly panel data, we estimate a dynamic spatial autoregressive (SAR) model to elucidate the short- and the long-run impact of vaccination on Covid-19 incidence growth after controlling for temporal and spatio-temporal diffusion, testing capacity, social distancing behavior and unobserved space-varying confounders. Results show that vaccination growth reduces Covid-19 incidence growth rate directly and indirectly by creating a positive externality over space. The significant association between vaccination and Covid-19 incidence is robust to a host of spatial weight matrix specifications. Conspicuous spatial and temporal diffusion effects of Covid-19 incidence growth were found across all specifications: the former being a severer threat to the containment of the pandemic than the latter.Article Citation - WoS: 27Citation - Scopus: 30Prevalence 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, OnurBackground : 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 ImmunologyArticle Citation - WoS: 44Citation - Scopus: 49Population Density Index and Its Use for Distribution of Covid-19: a Case Study Using Turkish Data(Elsevier, 2021-02-01) Başer, OnurSince 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: 15Citation - Scopus: 15Economic 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, AhongIntroduction: 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: 10Citation - Scopus: 12Elevated 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, SulenaBackground: 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 AuthorsArticle Citation - WoS: 13Citation - Scopus: 13Risk 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, OnurNew-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: 6Citation - Scopus: 6Health 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, AntoineThere 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 - WoS: 7Citation - Scopus: 8The 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, OnurBackground: 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.Article Citation - WoS: 18Citation - Scopus: 18Adding Rapid-Acting Insulin or Glp-1 Receptor Agonist To Basal Insulin: Outcomes in a Community Setting(Amer Assoc Clinical Endocrinologists, 2015) Dalal, Mehul R; DiGenio, Andres; Xie, Lin; Başer, OnurTo evaluate real-world outcomes in patients with type 2 diabetes mellitus (T2DM)receiving basal insulin, who initiate add-on therapy with a rapid-acting insulin (RAI) or aglucagon-like peptide 1 (GLP-1) receptor agonist.Data were extracted retrospectively from a U.S. health claims database. Adults withT2DM on basal insulin who added an RAI (basal+RAI) or GLP-1 receptor agonist (basal+GLP-1) were included. Propensity score matching (1 up to 3 ratio) was used to control for differencesin baseline demographics, clinical characteristics, and health resource utilization. Endpointsincluded prevalence of hypoglycemia, pancreatic events, all-cause and diabetes-relatedresource utilization, and costs at 1 year follow-up. Overall, 6,718 matched patients were included: 5,013 basal+RAI and 1,705basal+GLP1. Patients in both groups experienced a similar proportion of any hypoglycemicevent (P = .4079). Hypoglycemic events leading to hospitalization were higher in the basal+RAIcohort (2.7% vs. 1.8%; P = .0444). The basal+GLP-1 cohort experienced fewer all-cause(13.55% vs. 18.61%; P<.0001) and diabetes-related hospitalizations (11.79% vs. 15.68%;P<.0001). The basal+GLP-1 cohort had lower total all-cause health care costs ($18,413 vs.$20,821; P = .0002), but similar diabetes-related costs ($9,134 vs. $8,985; P<.0001) comparedwith the basal+RAI cohort. Add-on therapy with a GLP-1 receptor agonist in T2DM patients receiving basalinsulin was associated with fewer hospitalizations and lower total all-cause costs compared withadd-on therapy using a RAI, and could be considered an alternative to a RAI in certain patientswith T2DM, who do not achieve effective glycemic control with basal insulin.Article Citation - WoS: 3Citation - Scopus: 3Cancer Chemotherapy Treatment Patterns and Febrile Neutropenia in the Us Veterans Health Administration(Elsevier Science Inc, 2014-09-01) Wang, Li; Dale, David C; Barron, Richard; Langeberg, Wendy J; Başer, OnurBackground: The Veterans Health Administration (VHA) is the largest integrated health care system in the United States and a major cancer care provider. Objective: To use VHA database to conduct a population-based study of patterns of myelosuppressive chemotherapy use and to assess the incidence and management of febrile neutropenia (FN) among VHA patients with lung, colorectal, or prostate cancer or non-Hodgkin lymphoma (NHL). Methods: Data were extracted for the initial myelosuppressive chemotherapy course for 27,899 patients who began treatment in the period 2006 to 2011. FN-related costs were defined as claims containing FN diagnosis. Results: Most patients were men (98.0%); most were 65 years or older (55.8%). Patients received a mean 3.4 to 3.9 chemotherapy cycles/course (median cycle duration 34-43 days). The incidence of FN among patients with lung, colorectal, or prostate cancer or NHL was 10.2%, 4.6%, 5.4%, and 17.3%, respectively. Primary or secondary prophylactic antibiotics/colony-stimulating factors were received by 21% and 12% of patients, respectively. Antibiotics were more commonly given as primary or secondary prophylaxis for patients with lung, colorectal, and prostate cancer; colony-stimulating factors were more common for patients with NHL. Among patients with FN, those with lung cancer had the highest inpatient mortality (10%); patients with NHL had the highest costs ($24,571) and the longest hospital length of stay (15.4 days). Conclusions: VHA cancer care was generally consistent with National Comprehensive Cancer Network recommendations; however, compared with the general population, chemotherapy cycles were longer, combination chemotherapy was used less, and treatment to prevent FN was used less, differences that may be attributed to the unique VHA patient population. The impact of these practices warrants further investigation.