Barbara K. Zedler
Research Subjects
Barbara K. Zedler has a total of 50 co-authors. Here are the top co-authors by number of shared publications:
Lenn Murrelle
Venebio Group, LLC, Richmond, Virginia
4 shared publicationsAndrew Joyce
Venebio Group, LLC, Richmond, Virginia
3 shared publicationsAndrew R Joyce
Venebio Group, LLC, Richmond, Virginia
2 shared publicationsAndrew R. Joyce
Venebio Group, LLC Richmond VA USA
2 shared publicationsCatherine Vick
Venebio Group, LLC, Richmond, Virginia
2 shared publicationsE Lenn Murrelle
Venebio Group, LLC, Richmond, Virginia
2 shared publications
Latest Publications
- Open Access
- 13 April 2017
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 19 (1) , 79-96
Risk Factors for Serious Prescription Opioid-Induced Respiratory Depression or Overdose: Comparison of Commercially Insured and Veterans Health Affairs Populations
To characterize the risk factors associated with overdose or serious opioid-induced respiratory depression (OIRD) among medical users of prescription opioids in a commercially insured population (CIP) and to compare risk factor profiles between the CIP and Veterans Health Administration (VHA) population. Analysis of data from 18,365,497 patients in the IMS PharMetrics Plus health plan claims database (CIP) who were dispensed a prescription opioid in 2009 to 2013. Baseline factors associated with an event of serious OIRD among 7,234 cases and 28,932 controls were identified using multivariable logistic regression. The CIP risk factor profile was compared with that from a corresponding logistic regression among 817 VHA cases and 8,170 controls in 2010 to 2012. The strongest associations with serious OIRD in CIP were diagnosed substance use disorder (odds ratio [OR] = 10.20, 95% confidence interval [CI] = 9.06–11.40) and depression (OR = 3.12, 95% CI = 2.84–3.42). Other strongly associated factors included other mental health disorders; impaired liver, renal, vascular, and pulmonary function; prescribed fentanyl, methadone, and morphine; higher daily opioid doses; and concurrent psychoactive medications. These risk factors, except depression, vascular disease, and specific opioids, largely aligned with VHA despite CIP being substantially younger, including more females and less chronic disease, and having greater prescribing prevalence of higher daily opioid doses, specific opioids, and most selected nonopioids. Risk factor profiles for serious OIRD among US medical users of prescription opioids with private or public health insurance were largely concordant despite substantial differences between the populations in demographics, clinical conditions, health care delivery systems, and clinical practices.
- 13 April 2017
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 19 (1) , 79-96
Open AccessRisk Factors for Serious Prescription Opioid-Induced Respiratory Depression or Overdose: Comparison of Commercially Insured and Veterans Health Affairs Populations
To characterize the risk factors associated with overdose or serious opioid-induced respiratory depression (OIRD) among medical users of prescription opioids in a commercially insured population (CIP) and to compare risk factor profiles between the CIP and Veterans Health Administration (VHA) population. Analysis of data from 18,365,497 patients in the IMS PharMetrics Plus health plan claims database (CIP) who were dispensed a prescription opioid in 2009 to 2013. Baseline factors associated with an event of serious OIRD among 7,234 cases and 28,932 controls were identified using multivariable logistic regression. The CIP risk factor profile was compared with that from a corresponding logistic regression among 817 VHA cases and 8,170 controls in 2010 to 2012. The strongest associations with serious OIRD in CIP were diagnosed substance use disorder (odds ratio [OR] = 10.20, 95% confidence interval [CI] = 9.06–11.40) and depression (OR = 3.12, 95% CI = 2.84–3.42). Other strongly associated factors included other mental health disorders; impaired liver, renal, vascular, and pulmonary function; prescribed fentanyl, methadone, and morphine; higher daily opioid doses; and concurrent psychoactive medications. These risk factors, except depression, vascular disease, and specific opioids, largely aligned with VHA despite CIP being substantially younger, including more females and less chronic disease, and having greater prescribing prevalence of higher daily opioid doses, specific opioids, and most selected nonopioids. Risk factor profiles for serious OIRD among US medical users of prescription opioids with private or public health insurance were largely concordant despite substantial differences between the populations in demographics, clinical conditions, health care delivery systems, and clinical practices.
- Open Access
- 6 March 2017
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 19 (1) , 68-78
Validation of a Screening Risk Index for Serious Prescription Opioid-Induced Respiratory Depression or Overdose in a US Commercial Health Plan Claims Database
To validate a risk index that estimates the likelihood of overdose or serious opioid-induced respiratory depression (OIRD) among medical users of prescription opioids. A case-control analysis of 18,365,497 patients with an opioid prescription from 2009 to 2013 in the IMS PharMetrics Plus commercially insured health plan claims database (CIP). An OIRD event occurred in 7,234 cases. Four controls were selected per case. Validity of the Risk Index for Overdose or Serious Opioid-induced Respiratory Depression (RIOSORD), developed previously using Veterans Health Administration (VHA) patient data, was assessed. Multivariable logistic regression was used within the CIP study population to develop a slightly refined RIOSORD. The composition and performance of the CIP-based RIOSORD was evaluated and compared with VHA-based RIOSORD. VHA-RIOSORD performed well in discriminating OIRD events in CIP (C-statistic = 0.85). Additionally, re-estimation of logistic model coefficients in CIP yielded a 0.90 C-statistic. The resulting comorbidity and pharmacotherapy variables most highly associated with OIRD and retained in the CIP-RIOSORD were largely concordant with VHA-RIOSORD. These variables included neuropsychiatric and cardiopulmonary disorders, impaired drug excretion, opioid characteristics, and concurrent psychoactive medications. The average predicted probability of OIRD ranged from 2% to 83%, with excellent agreement between predicted and observed incidence across risk classes. RIOSORD had excellent predictive accuracy in a large population of US medical users of prescription opioids, similar to its performance in VHA. This practical risk index is designed to support clinical decision-making for safer opioid prescribing, and its clinical utility should be evaluated prospectively.
- 6 March 2017
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 19 (1) , 68-78
Open AccessValidation of a Screening Risk Index for Serious Prescription Opioid-Induced Respiratory Depression or Overdose in a US Commercial Health Plan Claims Database
To validate a risk index that estimates the likelihood of overdose or serious opioid-induced respiratory depression (OIRD) among medical users of prescription opioids. A case-control analysis of 18,365,497 patients with an opioid prescription from 2009 to 2013 in the IMS PharMetrics Plus commercially insured health plan claims database (CIP). An OIRD event occurred in 7,234 cases. Four controls were selected per case. Validity of the Risk Index for Overdose or Serious Opioid-induced Respiratory Depression (RIOSORD), developed previously using Veterans Health Administration (VHA) patient data, was assessed. Multivariable logistic regression was used within the CIP study population to develop a slightly refined RIOSORD. The composition and performance of the CIP-based RIOSORD was evaluated and compared with VHA-based RIOSORD. VHA-RIOSORD performed well in discriminating OIRD events in CIP (C-statistic = 0.85). Additionally, re-estimation of logistic model coefficients in CIP yielded a 0.90 C-statistic. The resulting comorbidity and pharmacotherapy variables most highly associated with OIRD and retained in the CIP-RIOSORD were largely concordant with VHA-RIOSORD. These variables included neuropsychiatric and cardiopulmonary disorders, impaired drug excretion, opioid characteristics, and concurrent psychoactive medications. The average predicted probability of OIRD ranged from 2% to 83%, with excellent agreement between predicted and observed incidence across risk classes. RIOSORD had excellent predictive accuracy in a large population of US medical users of prescription opioids, similar to its performance in VHA. This practical risk index is designed to support clinical decision-making for safer opioid prescribing, and its clinical utility should be evaluated prospectively.
- Open Access
Buprenorphine compared with methadone to treat pregnant women with opioid use disorder: a systematic review and meta‐analysis of safety in the mother, fetus and child
Aims: To assess the safety of buprenorphine compared with methadone to treat pregnant women with opioid use disorder. Methods: We searched PubMed, Embase and the Cochrane Library from inception to February 2015 for randomized controlled trials (RCT) and observational cohort studies (OBS) that compared buprenorphine with methadone for treating opioid‐dependent pregnant women. Two reviewers assessed independently the titles and abstracts of all search results and full texts of potentially eligible studies reporting original data for maternal/fetal/infant death, preterm birth, fetal growth outcomes, fetal/congenital anomalies, fetal/child neurodevelopment and/or maternal adverse events. We ascertained each study's risk of bias using validated instruments and assessed the strength of evidence for each outcome using established methods. We computed effect sizes using random‐effects models for each outcome with two or more studies. Results: Three RCTs ( n = 223) and 15 cohort OBSs ( n = 1923) met inclusion criteria. In meta‐analyses using unadjusted data and methadone as comparator, buprenorphine was associated with lower risk of preterm birth [RCT risk ratio (RR) = 0.40, 95% confidence interval (CI) = 0.18, 0.91; OBS RR = 0.67, 95% CI = 0.50, 0.90], greater birth weight [RCT weighted mean difference (WMD) = 277 g, 95% CI = 104, 450; OBS WMD = 265 g, 95% CI = 196, 335] and larger head circumference [RCT WMD = 0.90 cm, 95% CI = 0.14, 1.66; OBS WMD = 0.68 cm, 95% CI = 0.41, 0.94]. No treatment differences were observed for spontaneous fetal death, fetal/congenital anomalies and other fetal growth measures, although the power to detect such differences may be inadequate due to small sample sizes. Conclusions: Moderately strong evidence indicates lower risk of preterm birth, greater birth weight and larger head circumference with buprenorphine treatment of maternal opioid use disorder during pregnancy compared with methadone treatment, and no greater harms.
Open AccessBuprenorphine compared with methadone to treat pregnant women with opioid use disorder: a systematic review and meta‐analysis of safety in the mother, fetus and child
Aims: To assess the safety of buprenorphine compared with methadone to treat pregnant women with opioid use disorder. Methods: We searched PubMed, Embase and the Cochrane Library from inception to February 2015 for randomized controlled trials (RCT) and observational cohort studies (OBS) that compared buprenorphine with methadone for treating opioid‐dependent pregnant women. Two reviewers assessed independently the titles and abstracts of all search results and full texts of potentially eligible studies reporting original data for maternal/fetal/infant death, preterm birth, fetal growth outcomes, fetal/congenital anomalies, fetal/child neurodevelopment and/or maternal adverse events. We ascertained each study's risk of bias using validated instruments and assessed the strength of evidence for each outcome using established methods. We computed effect sizes using random‐effects models for each outcome with two or more studies. Results: Three RCTs ( n = 223) and 15 cohort OBSs ( n = 1923) met inclusion criteria. In meta‐analyses using unadjusted data and methadone as comparator, buprenorphine was associated with lower risk of preterm birth [RCT risk ratio (RR) = 0.40, 95% confidence interval (CI) = 0.18, 0.91; OBS RR = 0.67, 95% CI = 0.50, 0.90], greater birth weight [RCT weighted mean difference (WMD) = 277 g, 95% CI = 104, 450; OBS WMD = 265 g, 95% CI = 196, 335] and larger head circumference [RCT WMD = 0.90 cm, 95% CI = 0.14, 1.66; OBS WMD = 0.68 cm, 95% CI = 0.41, 0.94]. No treatment differences were observed for spontaneous fetal death, fetal/congenital anomalies and other fetal growth measures, although the power to detect such differences may be inadequate due to small sample sizes. Conclusions: Moderately strong evidence indicates lower risk of preterm birth, greater birth weight and larger head circumference with buprenorphine treatment of maternal opioid use disorder during pregnancy compared with methadone treatment, and no greater harms.
- Open Access
- 7 September 2015
- Published by Springer Nature in BMC Public Health
- Vol. 15 (1) , 866
Total Exposure Study Analysis consortium: a cross-sectional study of tobacco exposures
The Total Exposure Study was a stratified, multi-center, cross-sectional study designed to estimate levels of biomarkers of tobacco-specific and non-specific exposure and of potential harm in U.S. adult current cigarette smokers (≥one manufactured cigarette per day over the last year) and tobacco product non-users (no smoking or use of any nicotine containing products over the last 5 years). The study was designed and sponsored by a tobacco company and implemented by contract research organizations in 2002–2003. Multiple analyses of smoking behavior, demographics, and biomarkers were performed. Study data and banked biospecimens were transferred from the sponsor to the Virginia Tobacco and Health Research Repository in 2010, and then to SRI International in 2012, for independent analysis and dissemination. We analyzed biomarker distributions overall, and by biospecimen availability, for comparison with existing studies, and to evaluate generalizability to the entire sample. We calculated genome-wide statistical power for a priori hypotheses. We performed clinical chemistries, nucleic acid extractions and genotyping, and report correlation and quality control metrics. Vital signs, clinical chemistries, and laboratory measures of tobacco specific and non-specific toxicants are available from 3585 current cigarette smokers, and 1077 non-users. Peripheral blood mononuclear cells, red blood cells, plasma and 24-h urine biospecimens are available from 3073 participants (2355 smokers and 719 non-users). In multivariate analysis, participants with banked biospecimens were significantly more likely to self-identify as White, to be older, to have increased total nicotine equivalents per cigarette, decreased serum cotinine, and increased forced vital capacity, compared to participants without. Effect sizes were small (Cohen’s d-values ≤ 0.11). Power for a priori hypotheses was 57 % in non-Hispanic Black (N = 340), and 96 % in non-Hispanic White (N = 1840), smokers. All DNA samples had genotype completion rates ≥97.5 %; 68 % of RNA samples yielded RIN scores ≥6.0. Total Exposure Study clinical and laboratory assessments and biospecimens comprise a unique resource for cigarette smoke health effects research. The Total Exposure Study Analysis Consortium seeks to perform molecular studies in multiple domains and will share data and analytic results in public repositories and the peer-reviewed literature. Data and banked biospecimens are available for independent or collaborative research.
- 7 September 2015
- Published by Springer Nature in BMC Public Health
- Vol. 15 (1) , 866
Open AccessTotal Exposure Study Analysis consortium: a cross-sectional study of tobacco exposures
The Total Exposure Study was a stratified, multi-center, cross-sectional study designed to estimate levels of biomarkers of tobacco-specific and non-specific exposure and of potential harm in U.S. adult current cigarette smokers (≥one manufactured cigarette per day over the last year) and tobacco product non-users (no smoking or use of any nicotine containing products over the last 5 years). The study was designed and sponsored by a tobacco company and implemented by contract research organizations in 2002–2003. Multiple analyses of smoking behavior, demographics, and biomarkers were performed. Study data and banked biospecimens were transferred from the sponsor to the Virginia Tobacco and Health Research Repository in 2010, and then to SRI International in 2012, for independent analysis and dissemination. We analyzed biomarker distributions overall, and by biospecimen availability, for comparison with existing studies, and to evaluate generalizability to the entire sample. We calculated genome-wide statistical power for a priori hypotheses. We performed clinical chemistries, nucleic acid extractions and genotyping, and report correlation and quality control metrics. Vital signs, clinical chemistries, and laboratory measures of tobacco specific and non-specific toxicants are available from 3585 current cigarette smokers, and 1077 non-users. Peripheral blood mononuclear cells, red blood cells, plasma and 24-h urine biospecimens are available from 3073 participants (2355 smokers and 719 non-users). In multivariate analysis, participants with banked biospecimens were significantly more likely to self-identify as White, to be older, to have increased total nicotine equivalents per cigarette, decreased serum cotinine, and increased forced vital capacity, compared to participants without. Effect sizes were small (Cohen’s d-values ≤ 0.11). Power for a priori hypotheses was 57 % in non-Hispanic Black (N = 340), and 96 % in non-Hispanic White (N = 1840), smokers. All DNA samples had genotype completion rates ≥97.5 %; 68 % of RNA samples yielded RIN scores ≥6.0. Total Exposure Study clinical and laboratory assessments and biospecimens comprise a unique resource for cigarette smoke health effects research. The Total Exposure Study Analysis Consortium seeks to perform molecular studies in multiple domains and will share data and analytic results in public repositories and the peer-reviewed literature. Data and banked biospecimens are available for independent or collaborative research.
- Open Access
- 1 August 2015
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 16 (8) , 1566-1579
Development of a Risk Index for Serious Prescription Opioid-Induced Respiratory Depression or Overdose in Veterans' Health Administration Patients
Objective. Develop a risk index to estimate the likelihood of life-threatening respiratory depression or overdose among medical users of prescription op
- 1 August 2015
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 16 (8) , 1566-1579
Open AccessDevelopment of a Risk Index for Serious Prescription Opioid-Induced Respiratory Depression or Overdose in Veterans' Health Administration Patients
Objective. Develop a risk index to estimate the likelihood of life-threatening respiratory depression or overdose among medical users of prescription op
- 1 November 2014
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 15 (11) , 1911-1929
Risk Factors for Serious Prescription Opioid-Related Toxicity or Overdose among Veterans Health Administration Patients
Prescription opioid use and deaths related to serious toxicity, including overdose, have increased dramatically in the United States since 1999. However, factors associated with serious opioid-related respiratory or central nervous system (CNS) depression or overdose in medical users are not well characterized. The objective of this study was to examine the factors associated with serious toxicity in medical users of prescription opioids. Retrospective, nested, case-control analysis of Veterans Health Administration (VHA) medical, pharmacy, and health care resource utilization administrative data. Patients dispensed an opioid by VHA between October 1, 2010 and September 30, 2012 (N=8,987). Cases (N=817) experienced life-threatening opioid-related respiratory/CNS depression or overdose. Ten controls were randomly assigned to each case (N=8,170). Logistic regression was used to examine associations with the outcome. The strongest associations were maximum prescribed daily morphine equivalent dose (MED)≥ 100 mg (odds ratio [OR]=4.1, 95% confidence interval [CI], 2.6-6.5), history of opioid dependence (OR=3.9, 95% CI, 2.6-5.8), and hospitalization during the 6 months before the serious toxicity or overdose event (OR=2.9, 95% CI, 2.3-3.6). Liver disease, extended-release or long-acting opioids, and daily MED of 20 mg or more were also significantly associated. Substantial risk for serious opioid-related toxicity and overdose exists at even relatively low maximum prescribed daily MED, especially in patients already vulnerable due to underlying demographic factors, comorbid conditions, and concomitant use of CNS depressant medications or substances. Screening patients for risk, providing education, and coprescribing naloxone for those at elevated risk may be effective at reducing serious opioid-related respiratory/CNS depression and overdose in medical users of prescription opioids.
- 1 November 2014
- Published by Oxford University Press (OUP) in Pain Medicine
- Vol. 15 (11) , 1911-1929
Risk Factors for Serious Prescription Opioid-Related Toxicity or Overdose among Veterans Health Administration Patients
Prescription opioid use and deaths related to serious toxicity, including overdose, have increased dramatically in the United States since 1999. However, factors associated with serious opioid-related respiratory or central nervous system (CNS) depression or overdose in medical users are not well characterized. The objective of this study was to examine the factors associated with serious toxicity in medical users of prescription opioids. Retrospective, nested, case-control analysis of Veterans Health Administration (VHA) medical, pharmacy, and health care resource utilization administrative data. Patients dispensed an opioid by VHA between October 1, 2010 and September 30, 2012 (N=8,987). Cases (N=817) experienced life-threatening opioid-related respiratory/CNS depression or overdose. Ten controls were randomly assigned to each case (N=8,170). Logistic regression was used to examine associations with the outcome. The strongest associations were maximum prescribed daily morphine equivalent dose (MED)≥ 100 mg (odds ratio [OR]=4.1, 95% confidence interval [CI], 2.6-6.5), history of opioid dependence (OR=3.9, 95% CI, 2.6-5.8), and hospitalization during the 6 months before the serious toxicity or overdose event (OR=2.9, 95% CI, 2.3-3.6). Liver disease, extended-release or long-acting opioids, and daily MED of 20 mg or more were also significantly associated. Substantial risk for serious opioid-related toxicity and overdose exists at even relatively low maximum prescribed daily MED, especially in patients already vulnerable due to underlying demographic factors, comorbid conditions, and concomitant use of CNS depressant medications or substances. Screening patients for risk, providing education, and coprescribing naloxone for those at elevated risk may be effective at reducing serious opioid-related respiratory/CNS depression and overdose in medical users of prescription opioids.
- 1 May 2011
- Published by Elsevier in Clinical Therapeutics
- Vol. 33 (5) , 581-597
A Pharmacoepidemiologic Analysis of the Impact of Calendar Packaging on Adherence to Self-Administered Medications for Long-Term Use
- 1 May 2011
- Published by Elsevier in Clinical Therapeutics
- Vol. 33 (5) , 581-597
A Pharmacoepidemiologic Analysis of the Impact of Calendar Packaging on Adherence to Self-Administered Medications for Long-Term Use
- 1 January 2011
- Published by Elsevier in Clinical Therapeutics
- Vol. 33 (1) , 62-73
Does Packaging with a Calendar Feature Improve Adherence to Self-Administered Medication for Long-Term Use? A Systematic Review
- 1 January 2011
- Published by Elsevier in Clinical Therapeutics
- Vol. 33 (1) , 62-73
Does Packaging with a Calendar Feature Improve Adherence to Self-Administered Medication for Long-Term Use? A Systematic Review
- 30 June 2010
- Published by Elsevier in Regulatory Toxicology and Pharmacology
- Vol. 57 (1) , 11-17
Further considerations on the evaluation of potential reduced-risk tobacco products. Part II: Re-assessment of a heuristic using the CPS-II database
- 30 June 2010
- Published by Elsevier in Regulatory Toxicology and Pharmacology
- Vol. 57 (1) , 11-17
Further considerations on the evaluation of potential reduced-risk tobacco products. Part II: Re-assessment of a heuristic using the CPS-II database