Erdem Baser - Academia.edu (original) (raw)

Papers by Erdem Baser

Research paper thumbnail of Research Article Health Care Costs Associated with Ankylosing Spondylitis in Turkey: An Analysis from Nationwide Real-World Data

Copyright © 2013 Onur Baser et al. This is an open access article distributed under the Creative ... more Copyright © 2013 Onur Baser et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey. Methods. Research-identified data from a system that processes claims for all Turkish health insurance funds were analyzed. Adult prevalent and incident AS patients with two AS visits at least 60 days apart, identified between June 1, 2010 and December 31, 2010, with at least 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient, and inpatient claims were compiled over the study period for the selected patients. Generalized linear models were used to estimate the expected annual costs, controlling for baseline demographic and clinical characteristics. Results. A total ...

Research paper thumbnail of ORIGINAL RESEARCH Coronary Angiography Utilization and Costs for Coronary Artery Bypass Graft Surgery Patients in Turkey

The Author(s) 2013. This article is published with open access at Springerlink.com Introduction: ... more The Author(s) 2013. This article is published with open access at Springerlink.com Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft surgery and its association with mortality, health care costs, and hospital quality in

Research paper thumbnail of PRM140 An Applied Comparison of Meta-Analysis Techniques Using Bacille Calmette Guerin Vaccine Studies

Value in Health, 2012

nase alfa therapy. A lung function test ("index") separated a 2-year pre-index period from a 2-ye... more nase alfa therapy. A lung function test ("index") separated a 2-year pre-index period from a 2-year post-index period for which intercepts and slopes were independently estimated. The comparator group included patients not yet reported to have received dornase alfa; their index lung function test was associated with their eighth or subsequent even-numbered birthday. Comparator patients could contribute more than one set of pre-and post-index periods and could also subsequently be included in the dornase alfa group. To account for the repeated use of patients, variance components were estimated at the patient level as well as the case level. Different subsets of the comparator cases were analyzed. RESULTS: There were 2230 dornase alfa patients; the comparator group included 5970 cases from 3517 patients. The estimated difference in change in slope was 0.73Ϯ.31 (Pϭ0.020). Subsetting comparators to 4985 cases from 2836 patients not also in the dornase alfa group gave 0.61Ϯ0.32 (Pϭ0.058); including each of those patients only the last time eligible gave 0.68Ϯ0.36 (Pϭ0.059). Subsetting to 3662 cases from 2030 patients never on dornase alfa gave 0.32Ϯ0.34 (Pϭ0.35). Patient-level variance components corresponding to difference in slope and difference in intercept were near zero and so were dropped. CONCLUSIONS: In longitudinal observational studies, patients should be included in each group for which they meet eligibility criteria, possibly multiple times (with appropriate covariance structures). This avoids bias from using future information to decide whether to include a patient and loss of power from limiting cases unnecessarily.

Research paper thumbnail of Applied Comparison of Meta-analysis Techniques

Journal of Health Economics and Outcomes Research

Background: Meta-analysis is an approach that combines findings from similar studies. The aggrega... more Background: Meta-analysis is an approach that combines findings from similar studies. The aggregation of study level data can provide precise estimates for outcomes of interest, allow for unique treatment comparisons, and explain the differences arising from conflicting study results. Proper meta-analysis includes five basic steps: identify relevant studies; extract summary data from each paper; compute study effect sizes, perform statistical analysis; and interpret and report the results. Objectives: This study aims to review meta-analysis methods and their assumptions, apply various meta-techniques to empirical data, and compare the results from each method. Methods: Three different meta-analysis techniques were applied to a dataset looking at the effects of the bacille Calmette-Guerin (BCG) vaccine on tuberculosis (TB). First, a fixed-effects model was applied; then a random-effects model; and third meta-regression with study-level covariates were added to the model. Overall and ...

Research paper thumbnail of Comparison of Daily Average Consumption Between Different Proton Pump Inhibitors in Patients with Gastroesophageal Reflux Disease

American Journal of Gastroenterology

Research paper thumbnail of Clinical and economic outcomes in patients with type 2 diabetes initiating insulin glargine using disposable pen vs exenatide

F1000posters, Nov 10, 2011

1 statinmEd rEsEarCh, ann arbor, mi, usa; 2 sanofi-avEntis u.s., bridgEWatEr, nJ, usa; 3 statinmE... more 1 statinmEd rEsEarCh, ann arbor, mi, usa; 2 sanofi-avEntis u.s., bridgEWatEr, nJ, usa; 3 statinmEd rEsEarCh, tilburg, nEthErlands • This observational analysis of routine clinical practice showed that, compared with EXE, GLA-P may be a more effective option due to its association with greater treatment persistence, greater A1C reduction without a significantly higher rate of hypoglycemia, and similar health care costs.

Research paper thumbnail of Economic Impact and Complications of Treated and Untreated Hepatitis C Virus Patients in Turkey

Value in Health Regional Issues, 2015

Background: According to the Turkish Ministry of Health's guidelines, standard double therapy, a ... more Background: According to the Turkish Ministry of Health's guidelines, standard double therapy, a combination of pegylated interferon-alpha and ribavirin, was the only treatment option for patients with hepatitis C virus (HCV) infection until the end of 2011. Objective: The primary objective was to compare risk-adjusted clinical and economic outcomes between treated and untreated patients with HCV infection. Methods: Patients with HCV infection were identified from the Turkish National Health Insurance Database (2009-2011) using International Classification of Diseases, 10th Revision, Clinical Modification codes. The first prescription date was designated as the index date. Mortality and hepatocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: Out of 12,990 patients included in the study, 1,583 were treated for HCV infection. Out of 2,467 patients who had a cirrhosis diagnosis, 231 were treated, whereas out of 10,523 patients without cirrhosis, 1,352 patients were treated. Treated patients were younger, less likely to be diagnosed with comorbid conditions, and less likely to reside in Central or Eastern Anatolia. After adjusting for baseline demographic and clinical factors, mortality (2.27% vs. 5.31%; P o 0.001) and HCC rates (0.69% vs. 1.96%; P o 0.001) were found to be lower for treated patients. Differences were more significant among patients diagnosed with cirrhosis. Treated patients incurred higher risk-adjusted annual costs (€6172 vs. €1680; P o 0.001), mainly because of pharmaceutical costs (€4918 vs. €583; P o 0.001). Conclusions: HCV infection treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Characteristics of Patients Who Switch From Twice Daily (BID) Proton Pump Inhibitors (PPI) to Once-Daily (QD) Dexlansoprazole or QD Other PPIs

Research paper thumbnail of AB0783 Medical costs associated with rheumatoid arthritis in turkey: an analysis of real-world data

Annals of the Rheumatic Diseases, 2013

ABSTRACT Background Health Transformation Programme implementation by the Turkish Ministry of Hea... more ABSTRACT Background Health Transformation Programme implementation by the Turkish Ministry of Health resulted in significant health system changes in Turkey.1 Recognizing the importance of information technology and health technology assessment, Turkey invested in stronger systems and data collection. MEDULA, a nationwide integrated system between health insurance and healthcare providers, was built to collect e-invoice information electronically in 2007. Rheumatoid arthritis (RA) costs in Turkey were analyzed for the first time using real-world data. Objectives Estimate and identify medical cost determinants associated with RA in Turkey using nationwide real-world data. Methods Data was obtained from MEDULA (2009-2011). Adult RA patients (ages 18-99) were identified (01JUN2010-31DEC2010), and were required to have two RA diagnoses ≥60 days apart, and were grouped as prevalent and incident cases. The first RA claim date was designated as the index date. Healthcare costs were examined following the index date. Descriptive and multivariate analyses are provided. Pharmacy, outpatient and inpatient claims were compiled. Generalized linear models were used to calculate expected annual costs after controlling for age, gender, region, comorbid conditions and medication. Results A total of 2,613 patients met all inclusion criteria (693 incident; 1,920 prevalent patients). Prevalent patients were older, less likely to reside in the Marmara region, had higher comorbidity index scores and were more likely to be prescribed non-steroidal anti-inflammatory drugs, biologics and disease-modifying anti-rheumatic drugs relative to incident patients. Average annual costs were €2,000 (incident) and €2,386 (prevalent), due to pharmacy costs (73%, incident; 60%, prevalent). For both groups, inpatient and outpatient costs were mostly due to physician costs. Costs did not significantly differ in terms of age or region, prior comorbid conditions and medication use significantly affected cost estimation. Conclusions RA annual costs were found to be lower in Turkey relative to estimates in Europe, yet a significant portion was due to pharmacy costs. Comparative effectiveness analyses may be useful to decrease RA pharmacy costs. References Akdag R. Progress Report 2008 Health Transformation Programme: Ministry of Health, Ankara; 2008. Disclosure of Interest None Declared

Research paper thumbnail of Severity index for rheumatoid arthritis and its association with health care costs and biologic therapy use in Turkey

Health Economics Review, 2013

Objective: This study aimed to apply the previously validated severity index for rheumatoid arthr... more Objective: This study aimed to apply the previously validated severity index for rheumatoid arthritis (SIFRA) to prevalent rheumatoid arthritis (RA) groups in Turkey and determine the effect of RA severity on health care costs and biologic use. Methods: This retrospective study used the Turkish national health insurance database MEDULA (June 1, 2009-December 31, 2011). Prevalent RA patients were required to be age 18 to 99, have two RA diagnoses at least 60 days apart and be continuously enrolled 1 year prior to (baseline period) and post (follow-up period) index date, which was the first RA claim during the identification period (June 1, 2010-December 31, 2010). SIFRA was calculated for the baseline period. Total health care costs and biologic use were examined for the follow-up period. The chi-square test was used to determine the association between SIFRA score terciles and outcomes. Generalized linear models were applied to determine health care costs while multivariate logistic regression determined the effect of SIFRA on outcome measures for biologic use. Results: A total of 1,920 patients were identified. The mean SIFRA score was 14.21, and 7.05 (49.57%) of the mean composed of clinical and functional status variables, followed by 6.32 (44.47%) for medications, 0.48 (3.40%) for radiology and laboratory findings, and 0.32 (2.25%) for extra-articular manifestation. There was a significant variation in scores across cities. After controlling for age, gender, region, and comorbidity index, patients in the high SIFRA tercile were 5.16 times more likely to be prescribed biologics (p<0.001, confidence interval [CI]: 3.46-7.69), and incurred annual health care costs that were €2,091 higher (p<0.001, CI: €1,557-€2,625) than those in the low SIFRA score tercile. Conclusion: RA severity varies throughout Turkey and is a significant determinant of health care costs and biologic therapy use. Therefore, future comparative effectiveness studies should include the severity measure in their analysis.

Research paper thumbnail of Health Care Costs Associated with Ankylosing Spondylitis in Turkey: An Analysis from Nationwide Real-World Data

International Journal of Rheumatology, 2013

Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey.Me... more Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey.Methods. Research-identified data from a system that processes claims for all Turkish health insurance funds were analyzed. Adult prevalent and incident AS patients with two AS visits at least 60 days apart, identified between June 1, 2010 and December 31, 2010, with at least 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient, and inpatient claims were compiled over the study period for the selected patients. Generalized linear models were used to estimate the expected annual costs, controlling for baseline demographic and clinical characteristics.Results. A total of 2.986 patients were identified, of which 603 were incident cases and 2.383 prevalent cases. The mean ages were 39 and 41 years, respectively, and 44% and 38% were women for incident and prevalent cases. Prevalent patients had higher comorbidity scor...

Research paper thumbnail of Coronary Angiography Utilization and Costs for Coronary Artery Bypass Graft Surgery Patients in Turkey

Cardiology and Therapy, 2013

Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft ... more Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft surgery and its association with mortality, health care costs, and hospital quality in Turkey. Methods: Using Turkish National Health Insurance Data (2009-2011) that included patients who underwent cardiac surgery, coronary angiography utilization was identified. Propensity score matching was used to compare survival rates and annual health care costs of patients in a coronary angiography excess-use group ([1 angiogram) and in a standard-therapy group (1 angiogram). The empirical Bayesian approach was used to combine mortality and hospital volume for quality index. The relationship between hospital quality and excess use of coronary angiography was assessed using Chi-squared tests. Results: Out of 20,126 patients identified, 7.27% of patients underwent excessive coronary angiography procedures (excess-use group), with an average annual cost at 9.7% higher than those who had a single angiography (standard-therapy group; P\0.01). Operational mortality associated with excessive use was significantly higher as well (7.4% versus 5.4%, P\0.02). There exists variation in the use of coronary angiography across cities and hospitals. Patients who underwent cardiac surgery in high-quality hospitals were less likely to have excessive angiography use than those in low-quality hospitals (7.0% versus 9.5%, P\0.01). Conclusion: In Turkey, excess use of coronary angiography prior to coronary artery bypass graft surgery is associated with higher O. Baser (&)

Research paper thumbnail of Economic Burden and Complications of Hepatitis C Virus Patients With and Without Peginterferon and Ribavirin Treatment in Turkey

Value in Health, 2014

tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were com... more tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: A total 12,990 patients, of whom 2,467 were diagnosed with cirrhosis, were included in the study. 12.2% of the overall population was treated for HCV. Treated patients were younger, less likely to reside in Central or Eastern Anatolia and less likely to have comorbidities. After adjusting for baseline demographic and clinical factors, mortality rates (2.27% vs. 5.31%, p< 0.001) and HCC rates (0.69% vs. 1.96%, p< 0.001) were significantly lower for treated HCV patients. The differences were more significant among cirrhosis patients. Total risk-adjusted annual costs were significantly higher for treated patients (€ 6,172 vs. € 1,680, p< 0.001), mainly due to higher pharmaceutical costs (€ 4,918 vs. € 583, p< 0.001). ConClusions: HCV treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Cost of Cirrhosis among Patients Diagnosed with Hepatitis C Virus in Turkey

Value in Health, 2014

tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were com... more tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: A total 12,990 patients, of whom 2,467 were diagnosed with cirrhosis, were included in the study. 12.2% of the overall population was treated for HCV. Treated patients were younger, less likely to reside in Central or Eastern Anatolia and less likely to have comorbidities. After adjusting for baseline demographic and clinical factors, mortality rates (2.27% vs. 5.31%, p< 0.001) and HCC rates (0.69% vs. 1.96%, p< 0.001) were significantly lower for treated HCV patients. The differences were more significant among cirrhosis patients. Total risk-adjusted annual costs were significantly higher for treated patients (€ 6,172 vs. € 1,680, p< 0.001), mainly due to higher pharmaceutical costs (€ 4,918 vs. € 583, p< 0.001). ConClusions: HCV treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Pharmacy Cost Calculator for Hepatitis C Virus Patients in Turkey

Research paper thumbnail of Direct medical costs associated with rheumatoid arthritis in Turkey: analysis from National Claims Database

Rheumatology International, 2013

This study aimed to estimate and identify determinants of direct medical costs associated with rh... more This study aimed to estimate and identify determinants of direct medical costs associated with rheumatoid arthritis (RA) in Turkey using nationwide real-world data. Using the Turkish National Health Insurance Database (2009-2011), RA patients (ages 18-99) were identified using International Classification of Disease Tenth Revision Clinical Modification (ICD-10-CM) codes. Patients were required to have two RA diagnoses at least 60 days apart and were grouped as prevalent and incident cases. The date of the first RA claim was identified for each patient and designated as the index date. Total healthcare costs were examined over the 12-month period following the index date. Descriptive and multivariate analyses are provided. Generalized linear models were used to calculate expected annual costs for incident and prevalent RA patients after controlling for age, gender, region, comorbid conditions and medication. A total of 2,613 patients met all inclusion criteria (693 incident; 1,920 prevalent patients). Prevalent patients were older, less likely to reside in the Marmara region, had higher comorbidity index scores and were more likely to use non-steroidal anti-inflammatory drugs, biologics and disease-modifying anti-rheumatic drugs relative to incident patients. Average direct annual costs were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,000 [(&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1,750, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,247) 95 % CI] for incident cases and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,385 [(&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,224, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,545) 95 % CI] for prevalent cases, most due to pharmacy costs (73 % for incident cases, 60 % for prevalent cases). For incident and prevalent cases, a significant portion of inpatient and outpatient costs were due to physician costs (31 % for incident cases, 40 % for prevalent cases). Although the costs were not significantly different in terms of age or region, prior comorbid conditions and medication use significantly affected the cost estimation. RA total annual costs were found to be lower in Turkey, relative to estimates in Europe. The significant portion of the annual costs was due to pharmaceutical expenditures. Comparative effectiveness analysis may be useful to decrease RA-related pharmacy costs.

Research paper thumbnail of SAT0541 Analysis of Health Care Costs Associated with Ankylosing Spondylitis in Turkey

Annals of the Rheumatic Diseases, 2013

ABSTRACT Background The economic burden of ankylosing spondylitis (AS) has been analyzed in other... more ABSTRACT Background The economic burden of ankylosing spondylitis (AS) has been analyzed in other countries, yet it is not well documented in Turkey. Therefore, Turkey has invested in MEDULA, a nationwide integrated system between health insurance and healthcare providers. Objectives To explore healthcare costs associated with AS in Turkey using nationwide real-world data. Methods Using International Classification of Disease Tenth Revision Clinical Modification (ICD-10-CM) codes, adult prevalent and incident AS patients (age 18-99) with two AS-related visits at least 60 days apart, identified between 06/01/2010 and 12/31/2010, with 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient and inpatient claims were compiled over the study period. Generalized linear models were used to estimate expected annual costs, controlling for baseline demographic and clinical characteristics. Results Total 2,986 patients were identified (603 incident, 2,383 prevalent cases). Most subjects were age 18-39 years (58% incident, 51% prevalent) and 44% of incident and 38% of prevalent cases were female. Prevalent patients had higher comorbidity index scores (6.04 vs. 2.24, p&lt;0.001). Risk-adjusted total annual medical costs were €2,253 for incident and €4,233 for prevalent patients. Pharmacy costs accounted for most of the total costs (89% prevalent; 77% incident). Conclusions Findings suggest that AS health care costs in Turkey resemble those in Europe. Costs are driven by comorbidities and treatment choices. Current data provides a baseline to evaluate economic effect of AS-related treatment and policy. Disclosure of Interest None Declared

Research paper thumbnail of PCV35 Comparison of Major Bleeding Related Mortality, Health Care Utilization and Costs of Patients with Non-Valvular Atrial Fibrillation

Value in Health, 2011

To determine association between heart failure (HF) and in-hospital mortality in ST-elevation myo... more To determine association between heart failure (HF) and in-hospital mortality in ST-elevation myocardial infarction (STEMI) patients treated with Percutaneous Coronary Intervention (PCI). METHODS: Retrospective analysis of I3 In-Vision Data Mart (2003-08). Adult enrollees (Ն18 years) with primary diagnosis of STEMI were selected if they were a) treated using PCI procedure and b) had continuous enrollment for at least 6 months prior to the STEMI-related index hospitalization (baseline). Enrollees were excluded if they underwent coronary artery bypass graft during index hospitalization. In-hospital morality was assessed based on an algorithm using claims data (or lack thereof) for STEMI patients after index hospitalization. Pre-existing HF was defined as presence of a claim with relevant HF diagnosis at baseline. New onset HF was defined as listing of HF as a comorbidity in the reimbursement claims for index hospitalization without supporting evidence for pre-existing HF at baseline. Multivariate logistic regression was used to assess association between HF status and in-hospital mortality. Priori significance level of 0.05 was used for these analyses. RESULTS: Overall 7261 enrollees were included in the analysis. Out of these, 187 (2.6%) had HF at baseline and 1,075 (14.8%) experienced HF for the first time. Out of 7261 enrollees, 351 (4.8%) died during index hospitalization. Chances of in-hospital mortality increased significantly with either pre-existing HF (absolute rate (AR): 9.6%, Odds Ratio (OR): 2.3, 95% Wald confidence limits (CI): 1.0-5.4), new onset HF (AR: 10.7%, OR ϭ 3.0, 95% CI: 2.3-3.8) or inclusion of pre-existing HF as a major comorbidity (AR: 16.7%, OR ϭ 3.9, 95% CI: 2.2-6.9) in index hospitalization claims. CONCLUSIONS: Presence of HF, recorded as either a pre-existing condition or as a major comorbid condition, in STEMI patients undergoing PCI was associated with significant increase in the in-hospital mortality.

Research paper thumbnail of PRM146 An Excel Calculator Tool to Perform Meta-Analysis

Research paper thumbnail of PMS20 Total Health Care Costs Associated With Rheumatoid Arthritis Incident Cases in Turkey

Research paper thumbnail of Research Article Health Care Costs Associated with Ankylosing Spondylitis in Turkey: An Analysis from Nationwide Real-World Data

Copyright © 2013 Onur Baser et al. This is an open access article distributed under the Creative ... more Copyright © 2013 Onur Baser et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey. Methods. Research-identified data from a system that processes claims for all Turkish health insurance funds were analyzed. Adult prevalent and incident AS patients with two AS visits at least 60 days apart, identified between June 1, 2010 and December 31, 2010, with at least 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient, and inpatient claims were compiled over the study period for the selected patients. Generalized linear models were used to estimate the expected annual costs, controlling for baseline demographic and clinical characteristics. Results. A total ...

Research paper thumbnail of ORIGINAL RESEARCH Coronary Angiography Utilization and Costs for Coronary Artery Bypass Graft Surgery Patients in Turkey

The Author(s) 2013. This article is published with open access at Springerlink.com Introduction: ... more The Author(s) 2013. This article is published with open access at Springerlink.com Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft surgery and its association with mortality, health care costs, and hospital quality in

Research paper thumbnail of PRM140 An Applied Comparison of Meta-Analysis Techniques Using Bacille Calmette Guerin Vaccine Studies

Value in Health, 2012

nase alfa therapy. A lung function test ("index") separated a 2-year pre-index period from a 2-ye... more nase alfa therapy. A lung function test ("index") separated a 2-year pre-index period from a 2-year post-index period for which intercepts and slopes were independently estimated. The comparator group included patients not yet reported to have received dornase alfa; their index lung function test was associated with their eighth or subsequent even-numbered birthday. Comparator patients could contribute more than one set of pre-and post-index periods and could also subsequently be included in the dornase alfa group. To account for the repeated use of patients, variance components were estimated at the patient level as well as the case level. Different subsets of the comparator cases were analyzed. RESULTS: There were 2230 dornase alfa patients; the comparator group included 5970 cases from 3517 patients. The estimated difference in change in slope was 0.73Ϯ.31 (Pϭ0.020). Subsetting comparators to 4985 cases from 2836 patients not also in the dornase alfa group gave 0.61Ϯ0.32 (Pϭ0.058); including each of those patients only the last time eligible gave 0.68Ϯ0.36 (Pϭ0.059). Subsetting to 3662 cases from 2030 patients never on dornase alfa gave 0.32Ϯ0.34 (Pϭ0.35). Patient-level variance components corresponding to difference in slope and difference in intercept were near zero and so were dropped. CONCLUSIONS: In longitudinal observational studies, patients should be included in each group for which they meet eligibility criteria, possibly multiple times (with appropriate covariance structures). This avoids bias from using future information to decide whether to include a patient and loss of power from limiting cases unnecessarily.

Research paper thumbnail of Applied Comparison of Meta-analysis Techniques

Journal of Health Economics and Outcomes Research

Background: Meta-analysis is an approach that combines findings from similar studies. The aggrega... more Background: Meta-analysis is an approach that combines findings from similar studies. The aggregation of study level data can provide precise estimates for outcomes of interest, allow for unique treatment comparisons, and explain the differences arising from conflicting study results. Proper meta-analysis includes five basic steps: identify relevant studies; extract summary data from each paper; compute study effect sizes, perform statistical analysis; and interpret and report the results. Objectives: This study aims to review meta-analysis methods and their assumptions, apply various meta-techniques to empirical data, and compare the results from each method. Methods: Three different meta-analysis techniques were applied to a dataset looking at the effects of the bacille Calmette-Guerin (BCG) vaccine on tuberculosis (TB). First, a fixed-effects model was applied; then a random-effects model; and third meta-regression with study-level covariates were added to the model. Overall and ...

Research paper thumbnail of Comparison of Daily Average Consumption Between Different Proton Pump Inhibitors in Patients with Gastroesophageal Reflux Disease

American Journal of Gastroenterology

Research paper thumbnail of Clinical and economic outcomes in patients with type 2 diabetes initiating insulin glargine using disposable pen vs exenatide

F1000posters, Nov 10, 2011

1 statinmEd rEsEarCh, ann arbor, mi, usa; 2 sanofi-avEntis u.s., bridgEWatEr, nJ, usa; 3 statinmE... more 1 statinmEd rEsEarCh, ann arbor, mi, usa; 2 sanofi-avEntis u.s., bridgEWatEr, nJ, usa; 3 statinmEd rEsEarCh, tilburg, nEthErlands • This observational analysis of routine clinical practice showed that, compared with EXE, GLA-P may be a more effective option due to its association with greater treatment persistence, greater A1C reduction without a significantly higher rate of hypoglycemia, and similar health care costs.

Research paper thumbnail of Economic Impact and Complications of Treated and Untreated Hepatitis C Virus Patients in Turkey

Value in Health Regional Issues, 2015

Background: According to the Turkish Ministry of Health's guidelines, standard double therapy, a ... more Background: According to the Turkish Ministry of Health's guidelines, standard double therapy, a combination of pegylated interferon-alpha and ribavirin, was the only treatment option for patients with hepatitis C virus (HCV) infection until the end of 2011. Objective: The primary objective was to compare risk-adjusted clinical and economic outcomes between treated and untreated patients with HCV infection. Methods: Patients with HCV infection were identified from the Turkish National Health Insurance Database (2009-2011) using International Classification of Diseases, 10th Revision, Clinical Modification codes. The first prescription date was designated as the index date. Mortality and hepatocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: Out of 12,990 patients included in the study, 1,583 were treated for HCV infection. Out of 2,467 patients who had a cirrhosis diagnosis, 231 were treated, whereas out of 10,523 patients without cirrhosis, 1,352 patients were treated. Treated patients were younger, less likely to be diagnosed with comorbid conditions, and less likely to reside in Central or Eastern Anatolia. After adjusting for baseline demographic and clinical factors, mortality (2.27% vs. 5.31%; P o 0.001) and HCC rates (0.69% vs. 1.96%; P o 0.001) were found to be lower for treated patients. Differences were more significant among patients diagnosed with cirrhosis. Treated patients incurred higher risk-adjusted annual costs (€6172 vs. €1680; P o 0.001), mainly because of pharmaceutical costs (€4918 vs. €583; P o 0.001). Conclusions: HCV infection treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Characteristics of Patients Who Switch From Twice Daily (BID) Proton Pump Inhibitors (PPI) to Once-Daily (QD) Dexlansoprazole or QD Other PPIs

Research paper thumbnail of AB0783 Medical costs associated with rheumatoid arthritis in turkey: an analysis of real-world data

Annals of the Rheumatic Diseases, 2013

ABSTRACT Background Health Transformation Programme implementation by the Turkish Ministry of Hea... more ABSTRACT Background Health Transformation Programme implementation by the Turkish Ministry of Health resulted in significant health system changes in Turkey.1 Recognizing the importance of information technology and health technology assessment, Turkey invested in stronger systems and data collection. MEDULA, a nationwide integrated system between health insurance and healthcare providers, was built to collect e-invoice information electronically in 2007. Rheumatoid arthritis (RA) costs in Turkey were analyzed for the first time using real-world data. Objectives Estimate and identify medical cost determinants associated with RA in Turkey using nationwide real-world data. Methods Data was obtained from MEDULA (2009-2011). Adult RA patients (ages 18-99) were identified (01JUN2010-31DEC2010), and were required to have two RA diagnoses ≥60 days apart, and were grouped as prevalent and incident cases. The first RA claim date was designated as the index date. Healthcare costs were examined following the index date. Descriptive and multivariate analyses are provided. Pharmacy, outpatient and inpatient claims were compiled. Generalized linear models were used to calculate expected annual costs after controlling for age, gender, region, comorbid conditions and medication. Results A total of 2,613 patients met all inclusion criteria (693 incident; 1,920 prevalent patients). Prevalent patients were older, less likely to reside in the Marmara region, had higher comorbidity index scores and were more likely to be prescribed non-steroidal anti-inflammatory drugs, biologics and disease-modifying anti-rheumatic drugs relative to incident patients. Average annual costs were €2,000 (incident) and €2,386 (prevalent), due to pharmacy costs (73%, incident; 60%, prevalent). For both groups, inpatient and outpatient costs were mostly due to physician costs. Costs did not significantly differ in terms of age or region, prior comorbid conditions and medication use significantly affected cost estimation. Conclusions RA annual costs were found to be lower in Turkey relative to estimates in Europe, yet a significant portion was due to pharmacy costs. Comparative effectiveness analyses may be useful to decrease RA pharmacy costs. References Akdag R. Progress Report 2008 Health Transformation Programme: Ministry of Health, Ankara; 2008. Disclosure of Interest None Declared

Research paper thumbnail of Severity index for rheumatoid arthritis and its association with health care costs and biologic therapy use in Turkey

Health Economics Review, 2013

Objective: This study aimed to apply the previously validated severity index for rheumatoid arthr... more Objective: This study aimed to apply the previously validated severity index for rheumatoid arthritis (SIFRA) to prevalent rheumatoid arthritis (RA) groups in Turkey and determine the effect of RA severity on health care costs and biologic use. Methods: This retrospective study used the Turkish national health insurance database MEDULA (June 1, 2009-December 31, 2011). Prevalent RA patients were required to be age 18 to 99, have two RA diagnoses at least 60 days apart and be continuously enrolled 1 year prior to (baseline period) and post (follow-up period) index date, which was the first RA claim during the identification period (June 1, 2010-December 31, 2010). SIFRA was calculated for the baseline period. Total health care costs and biologic use were examined for the follow-up period. The chi-square test was used to determine the association between SIFRA score terciles and outcomes. Generalized linear models were applied to determine health care costs while multivariate logistic regression determined the effect of SIFRA on outcome measures for biologic use. Results: A total of 1,920 patients were identified. The mean SIFRA score was 14.21, and 7.05 (49.57%) of the mean composed of clinical and functional status variables, followed by 6.32 (44.47%) for medications, 0.48 (3.40%) for radiology and laboratory findings, and 0.32 (2.25%) for extra-articular manifestation. There was a significant variation in scores across cities. After controlling for age, gender, region, and comorbidity index, patients in the high SIFRA tercile were 5.16 times more likely to be prescribed biologics (p<0.001, confidence interval [CI]: 3.46-7.69), and incurred annual health care costs that were €2,091 higher (p<0.001, CI: €1,557-€2,625) than those in the low SIFRA score tercile. Conclusion: RA severity varies throughout Turkey and is a significant determinant of health care costs and biologic therapy use. Therefore, future comparative effectiveness studies should include the severity measure in their analysis.

Research paper thumbnail of Health Care Costs Associated with Ankylosing Spondylitis in Turkey: An Analysis from Nationwide Real-World Data

International Journal of Rheumatology, 2013

Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey.Me... more Objectives. To explore health care costs associated with ankylosing spondylitis (AS) in Turkey.Methods. Research-identified data from a system that processes claims for all Turkish health insurance funds were analyzed. Adult prevalent and incident AS patients with two AS visits at least 60 days apart, identified between June 1, 2010 and December 31, 2010, with at least 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient, and inpatient claims were compiled over the study period for the selected patients. Generalized linear models were used to estimate the expected annual costs, controlling for baseline demographic and clinical characteristics.Results. A total of 2.986 patients were identified, of which 603 were incident cases and 2.383 prevalent cases. The mean ages were 39 and 41 years, respectively, and 44% and 38% were women for incident and prevalent cases. Prevalent patients had higher comorbidity scor...

Research paper thumbnail of Coronary Angiography Utilization and Costs for Coronary Artery Bypass Graft Surgery Patients in Turkey

Cardiology and Therapy, 2013

Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft ... more Introduction: To assess excess use of coronary angiography prior to coronary artery bypass graft surgery and its association with mortality, health care costs, and hospital quality in Turkey. Methods: Using Turkish National Health Insurance Data (2009-2011) that included patients who underwent cardiac surgery, coronary angiography utilization was identified. Propensity score matching was used to compare survival rates and annual health care costs of patients in a coronary angiography excess-use group ([1 angiogram) and in a standard-therapy group (1 angiogram). The empirical Bayesian approach was used to combine mortality and hospital volume for quality index. The relationship between hospital quality and excess use of coronary angiography was assessed using Chi-squared tests. Results: Out of 20,126 patients identified, 7.27% of patients underwent excessive coronary angiography procedures (excess-use group), with an average annual cost at 9.7% higher than those who had a single angiography (standard-therapy group; P\0.01). Operational mortality associated with excessive use was significantly higher as well (7.4% versus 5.4%, P\0.02). There exists variation in the use of coronary angiography across cities and hospitals. Patients who underwent cardiac surgery in high-quality hospitals were less likely to have excessive angiography use than those in low-quality hospitals (7.0% versus 9.5%, P\0.01). Conclusion: In Turkey, excess use of coronary angiography prior to coronary artery bypass graft surgery is associated with higher O. Baser (&)

Research paper thumbnail of Economic Burden and Complications of Hepatitis C Virus Patients With and Without Peginterferon and Ribavirin Treatment in Turkey

Value in Health, 2014

tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were com... more tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: A total 12,990 patients, of whom 2,467 were diagnosed with cirrhosis, were included in the study. 12.2% of the overall population was treated for HCV. Treated patients were younger, less likely to reside in Central or Eastern Anatolia and less likely to have comorbidities. After adjusting for baseline demographic and clinical factors, mortality rates (2.27% vs. 5.31%, p< 0.001) and HCC rates (0.69% vs. 1.96%, p< 0.001) were significantly lower for treated HCV patients. The differences were more significant among cirrhosis patients. Total risk-adjusted annual costs were significantly higher for treated patients (€ 6,172 vs. € 1,680, p< 0.001), mainly due to higher pharmaceutical costs (€ 4,918 vs. € 583, p< 0.001). ConClusions: HCV treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Cost of Cirrhosis among Patients Diagnosed with Hepatitis C Virus in Turkey

Value in Health, 2014

tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were com... more tocellular carcinoma (HCC) rates and health care costs of treated and untreated patients were compared using propensity score matching. Baseline demographic and clinical factors were controlled in the models. Subgroup analysis was conducted for patient groups with and without a cirrhosis diagnosis. Results: A total 12,990 patients, of whom 2,467 were diagnosed with cirrhosis, were included in the study. 12.2% of the overall population was treated for HCV. Treated patients were younger, less likely to reside in Central or Eastern Anatolia and less likely to have comorbidities. After adjusting for baseline demographic and clinical factors, mortality rates (2.27% vs. 5.31%, p< 0.001) and HCC rates (0.69% vs. 1.96%, p< 0.001) were significantly lower for treated HCV patients. The differences were more significant among cirrhosis patients. Total risk-adjusted annual costs were significantly higher for treated patients (€ 6,172 vs. € 1,680, p< 0.001), mainly due to higher pharmaceutical costs (€ 4,918 vs. € 583, p< 0.001). ConClusions: HCV treatment, although costly, significantly reduces mortality and HCC rates in Turkey.

Research paper thumbnail of Pharmacy Cost Calculator for Hepatitis C Virus Patients in Turkey

Research paper thumbnail of Direct medical costs associated with rheumatoid arthritis in Turkey: analysis from National Claims Database

Rheumatology International, 2013

This study aimed to estimate and identify determinants of direct medical costs associated with rh... more This study aimed to estimate and identify determinants of direct medical costs associated with rheumatoid arthritis (RA) in Turkey using nationwide real-world data. Using the Turkish National Health Insurance Database (2009-2011), RA patients (ages 18-99) were identified using International Classification of Disease Tenth Revision Clinical Modification (ICD-10-CM) codes. Patients were required to have two RA diagnoses at least 60 days apart and were grouped as prevalent and incident cases. The date of the first RA claim was identified for each patient and designated as the index date. Total healthcare costs were examined over the 12-month period following the index date. Descriptive and multivariate analyses are provided. Generalized linear models were used to calculate expected annual costs for incident and prevalent RA patients after controlling for age, gender, region, comorbid conditions and medication. A total of 2,613 patients met all inclusion criteria (693 incident; 1,920 prevalent patients). Prevalent patients were older, less likely to reside in the Marmara region, had higher comorbidity index scores and were more likely to use non-steroidal anti-inflammatory drugs, biologics and disease-modifying anti-rheumatic drugs relative to incident patients. Average direct annual costs were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,000 [(&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1,750, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,247) 95 % CI] for incident cases and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,385 [(&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,224, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;euro&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;2,545) 95 % CI] for prevalent cases, most due to pharmacy costs (73 % for incident cases, 60 % for prevalent cases). For incident and prevalent cases, a significant portion of inpatient and outpatient costs were due to physician costs (31 % for incident cases, 40 % for prevalent cases). Although the costs were not significantly different in terms of age or region, prior comorbid conditions and medication use significantly affected the cost estimation. RA total annual costs were found to be lower in Turkey, relative to estimates in Europe. The significant portion of the annual costs was due to pharmaceutical expenditures. Comparative effectiveness analysis may be useful to decrease RA-related pharmacy costs.

Research paper thumbnail of SAT0541 Analysis of Health Care Costs Associated with Ankylosing Spondylitis in Turkey

Annals of the Rheumatic Diseases, 2013

ABSTRACT Background The economic burden of ankylosing spondylitis (AS) has been analyzed in other... more ABSTRACT Background The economic burden of ankylosing spondylitis (AS) has been analyzed in other countries, yet it is not well documented in Turkey. Therefore, Turkey has invested in MEDULA, a nationwide integrated system between health insurance and healthcare providers. Objectives To explore healthcare costs associated with AS in Turkey using nationwide real-world data. Methods Using International Classification of Disease Tenth Revision Clinical Modification (ICD-10-CM) codes, adult prevalent and incident AS patients (age 18-99) with two AS-related visits at least 60 days apart, identified between 06/01/2010 and 12/31/2010, with 1 year of continuous health plan enrollment for the baseline and follow-up years were included in the study. Pharmacy, outpatient and inpatient claims were compiled over the study period. Generalized linear models were used to estimate expected annual costs, controlling for baseline demographic and clinical characteristics. Results Total 2,986 patients were identified (603 incident, 2,383 prevalent cases). Most subjects were age 18-39 years (58% incident, 51% prevalent) and 44% of incident and 38% of prevalent cases were female. Prevalent patients had higher comorbidity index scores (6.04 vs. 2.24, p&lt;0.001). Risk-adjusted total annual medical costs were €2,253 for incident and €4,233 for prevalent patients. Pharmacy costs accounted for most of the total costs (89% prevalent; 77% incident). Conclusions Findings suggest that AS health care costs in Turkey resemble those in Europe. Costs are driven by comorbidities and treatment choices. Current data provides a baseline to evaluate economic effect of AS-related treatment and policy. Disclosure of Interest None Declared

Research paper thumbnail of PCV35 Comparison of Major Bleeding Related Mortality, Health Care Utilization and Costs of Patients with Non-Valvular Atrial Fibrillation

Value in Health, 2011

To determine association between heart failure (HF) and in-hospital mortality in ST-elevation myo... more To determine association between heart failure (HF) and in-hospital mortality in ST-elevation myocardial infarction (STEMI) patients treated with Percutaneous Coronary Intervention (PCI). METHODS: Retrospective analysis of I3 In-Vision Data Mart (2003-08). Adult enrollees (Ն18 years) with primary diagnosis of STEMI were selected if they were a) treated using PCI procedure and b) had continuous enrollment for at least 6 months prior to the STEMI-related index hospitalization (baseline). Enrollees were excluded if they underwent coronary artery bypass graft during index hospitalization. In-hospital morality was assessed based on an algorithm using claims data (or lack thereof) for STEMI patients after index hospitalization. Pre-existing HF was defined as presence of a claim with relevant HF diagnosis at baseline. New onset HF was defined as listing of HF as a comorbidity in the reimbursement claims for index hospitalization without supporting evidence for pre-existing HF at baseline. Multivariate logistic regression was used to assess association between HF status and in-hospital mortality. Priori significance level of 0.05 was used for these analyses. RESULTS: Overall 7261 enrollees were included in the analysis. Out of these, 187 (2.6%) had HF at baseline and 1,075 (14.8%) experienced HF for the first time. Out of 7261 enrollees, 351 (4.8%) died during index hospitalization. Chances of in-hospital mortality increased significantly with either pre-existing HF (absolute rate (AR): 9.6%, Odds Ratio (OR): 2.3, 95% Wald confidence limits (CI): 1.0-5.4), new onset HF (AR: 10.7%, OR ϭ 3.0, 95% CI: 2.3-3.8) or inclusion of pre-existing HF as a major comorbidity (AR: 16.7%, OR ϭ 3.9, 95% CI: 2.2-6.9) in index hospitalization claims. CONCLUSIONS: Presence of HF, recorded as either a pre-existing condition or as a major comorbid condition, in STEMI patients undergoing PCI was associated with significant increase in the in-hospital mortality.

Research paper thumbnail of PRM146 An Excel Calculator Tool to Perform Meta-Analysis

Research paper thumbnail of PMS20 Total Health Care Costs Associated With Rheumatoid Arthritis Incident Cases in Turkey