PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.11779/1928
Browse
17 results
Search Results
Article Citation - WoS: 1Citation - Scopus: 1Understanding Covid-19 Mobility Through Human Capital: a Unified Causal Framework(Springer, 2023-02-21) Bilgel, Fırat; Karahasan, Burhan CanThis paper seeks to identify the causal impact of educational human capital on social distancing behavior at workplace in Turkey using district-level data for the period of April 2020 - February 2021. We adopt a unified causal framework, predicated on domain knowledge, theory-justified constraints anda data-driven causal structure discovery using causal graphs. We answer our causal query by employing machine learning prediction algorithms; instrumental variables in the presence of latent confounding and Heckman's model in the presence of selection bias. Results show that educated regions are able to distance-work and educational human capital is a key factor in reducing workplace mobility, possibly through its impact on employment. This pattern leads to higher workplace mobility for less educated regions and translates into higher Covid-19 infection rates. The future of the pandemic lies in less educated segments of developing countries and calls for public health action to decrease its unequal and pervasive impact.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: 7Citation - Scopus: 9Hematocrit 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, LiPatients 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: 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: 13Citation - Scopus: 13Therapeutically Interchangeable? a Study of Real-World Outcomes Associated With Switching Basal Insulin Analogues Among Us Patients With Type 2 Diabetes Mellitus Using Electronic Medical Records Data(Wiley, 2014-12-04) Wei, W.; Gill, J.; Ye, F; Xie, L; Levin, P.; Miao, R.; Başer, OnurAims: To evaluate real-world clinical outcomes for switching basal insulin analogues [insulin glargine (GLA) and insulin detemir (DET)] among US patients with type 2 diabetes mellitus (T2DM). Methods: Using the GE Centricity Electronic Medical Records database, this retrospective study examined two cohorts: cohort 1, comprising patients previously on GLA and then either switching to DET (DET-S) or continuing with GLA (GLA-C); and cohort 2, comprising patients previously on DET and then either switching to GLA (GLA-S) or continuing with DET (DET-C). Within each cohort, treatment groups were propensity-score-matched on baseline characteristics. At 1-year follow-up, insulin treatment patterns, glycated haemoglobin (HbA1c) levels, hypoglycaemic events, weight and body mass index (BMI) were evaluated. Results: The analysis included 13 942 patients: cohort 1: n= 10 657 (DET-S, n= 1797 matched to GLA-C, n= 8860) and cohort 2: n= 3285 (GLA-S, n= 858 matched to DET-C, n= 2427). Baseline characteristics were similar between the treatment groups in each cohort. At 1-year follow-up, in cohort 1, patients in the DET-S subgroup were significantly less persistent with treatment, more likely to use a rapid-acting insulin analogue, had higher HbA1c values, lower HbA1c reductions and lower proportions of patients achieving HbA1c < 7.0 or < 8.0% compared with patients in the GLA-C subgroup, while hypoglycaemia rates and BMI/weight values and change from baseline were similar in the two subgroups. In cohort 2, overall, there were contrasting findings between patients in the GLA-S and those in the DET-C subgroup. Conclusions: This study showed contrasting results when patients with T2DM switched between basal insulin analogues, although these preliminary results may be subject to limitations in the analysis. Nevertheless, this study calls into question the therapeutic interchangeability of GLA and DET, and this merits further investigation.Article Citation - WoS: 41Citation - Scopus: 39Clinical and Economic Burden Associated With Cardiovascular Events Among Patients With Hyperlipidemia: a Retrospective Cohort Study(BMC, 2016-01-14) Wang, Li; Quek, Ruben G. W; Fox, Kathleen M; Gandra, Shravanthi R; Li, Lu; Başer, OnurBackground: Annual direct costs for cardiovascular (CV) diseases in the United States are approximately $195.6 billion, with many high-risk patients remaining at risk for major cardiovascular events (CVE). This study evaluated the direct clinical and economic burden associated with new CVE up to 3 years post-event among patients with hyperlipidemia. Methods: Hyperlipidemic patients with a primary inpatient claim for new CVE (myocardial infarction, unstable angina, ischemic stroke, transient ischemic attack, coronary artery bypass graft, percutaneous coronary intervention and heart failure) were identified using IMS LifeLink PharMetrics Plus data from January 1, 2006 through June 30, 2012. Patients were stratified by CV risk into history of CVE, modified coronary heart disease risk equivalent, moderate-and low-risk cohorts. Of the eligible patients, propensity score matched 243,640 patients with or without new CVE were included to compare healthcare resource utilization and direct costs ranging from the acute (1-month) phase through 3 years post-CVE date (follow-up period). Results: Myocardial infarction was the most common CVE in all the risk cohorts. During the acute phase, among patients with new CVE, the average incremental inpatient length of stay and incremental costs ranged from 4.4-6.2 days and $25,666-$30,321, respectively. Acute-phase incremental costs accounted for 61-75 % of first-year costs, but incremental costs also remained high during years 2 and 3 post-CVE. Conclusions: Among hyperlipidemic patients with new CVE, healthcare utilization and costs incurred were significantly higher than for those without CVE during the acute phase, and remained higher up to 3 years post-event, across all risk cohorts.Editorial Citation - WoS: 15Citation - Scopus: 14Hepatic Decompensation in Patients With Hiv/Hepatitis B Virus (hbv)/Hepatitis C Virus (hcv) Triple Infection Versus Hiv/Hcv Coinfection and the Effect of Anti-Hbv Nucleos(t)ide Therapy(Oxford Univ Press Inc, 2014-06-18) Wang, Li; Devine, Scott; Lo Re, Vincent, III; Olufade, Temitope; Başer, Onur; Re, Vincent LoThe incidence rate of hepatic decompensation was higher in patients with human immunodeficiency virus (HIV)/hepatitis B virus (HBV)/hepatitis C virus (HCV) triple infection than in those with HIV/HCV coinfection (24.1 vs 10.8 events per 1000 person-years; hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.12–3.18). Compared with HIV/HCVinfected patients, the rate of decompensation was increased among HIV/HBV/HCV-infected patients receiving no anti-HBV therapy (HR, 2.48; 95% CI, 1.37–4.49) but not among those who did receive such therapy (HR, 1.09; 95% CI, .40–2.97)