Does radiofrequency ablation procedural data improve the accuracy of identifying atrial fibrillation recurrence?

Radiofrequency ablation (RFA) using the CARTO 3D mapping system is a common approach for pulmonary vein isolation to treat atrial fibrillation (AF). Linkage between CARTO procedural data and patients' electronical health records (EHR) provides an opportunity to identify the ablation-related parameters that would predict AF recurrence. The objective of this study is to assess the incremental accuracy of RFA procedural data to predict post-ablation AF recurrence using machine learning model. Procedural data generated during RFA procedure were downloaded from CARTONET and linked to deidentified Mercy Health EHR data. Data were divided into train (70%) and test (30%) data for model development and validation. Automate machine learning (AutoML) was used to predict 1 year AF recurrence, defined as a composite of repeat ablation, electrical cardioversion, and AF hospitalization. At first, AutoML model only included Patients' demographic and clinical characteristics. Second, an AutoML model with procedural variables and demographical/clinical variables was developed. Area under receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI) were used to compare model performances using test data. Among 306 patients, 67 (21.9%) patients experienced 1-year AF recurrence. AUROC increased from 0.66 to 0.78 after adding procedural data in the AutoML model based on test data. For patients with AF recurrence, NRI was 32% for model with procedural data. Nine of 10 important predictive features were CARTO procedural data. From CARTO procedural data, patients with lower contact force in right inferior site, long ablation duration, and low number of left inferior and right roof lesions had a higher risk of AF recurrence. Patients with persistent AF were more likely to have AF recurrence. The machine learning model with procedural data better predicted 1-year AF recurrence than the model without procedural data. The model could be used for identification of patients with high risk of AF recurrence post ablation.

Insurer costs of COVID-19 by disease severity and duration

OBJECTIVES

To analyze US commercial insurance payments associated with COVID-19 as a function of severity and duration of disease.

STUDY DESIGN

Retrospective database analysis.

METHODS

Patients with COVID-19 between April 1, 2020, and June 30, 2021, in the Merative MarketScan Commercial database were identified and stratified as having asymptomatic, mild, moderate (with and without lower respiratory disease), or severe/critical (S/C) disease based on the severity of the acute COVID-19 infection. Duration of disease (DOD) was estimated for all patients. Patients with DOD longer than 12 weeks were defined as having post-COVID-19 condition (PCC). Outcomes were all-cause payments (ACP) and disease-specific payments (DSP) for the entire DOD. Variables included demographic and comorbidities at the time of acute disease. Adjusted payments by disease severity were estimated using generalized linear models (γ distribution with log link).

RESULTS

A total of 738,339 patients were included (374,401 asymptomatic, 156,220 mild, 180,213 moderate, and 27,505 S/C cases). DSP increased from $217 (95% CI, $214-221) for asymptomatic cases to $2744 (95% CI, $2678-$2811) for moderate cases with lower respiratory disease and $28,250 (95% CI, $26,963-$29,538) for S/C cases. ACP increased from $505 (95% CI, $497-$512) for asymptomatic cases to $46,538 (95% CI, $44,096-$48,979) for S/C cases. The DSP and ACP further increased by $50,736 (95% CI, $45,337-$56,136) and $94,839 (95% CI, $88,029-$101,649), respectively, in S/C cases with PCC vs a DOD of fewer than 4 weeks.

CONCLUSIONS

COVID-19 payments for S/C cases were more than 10-fold greater than those of moderate cases and further increased by nearly $95,000 in S/C cases with PCC vs a DOD of fewer than 4 weeks.

Using real-world data from health systems to evaluate the safety and effectiveness of a catheter to treat ischemic ventricular tachycardia

BACKGROUND

The ThermoCool STSF catheter is used for ablation of ischemic ventricular tachycardia (VT) in routine clinical practice, although outcomes have not been studied and the catheter does not have Food and Drug Administration (FDA) approval for this indication. We used real-world health system data to evaluate its safety and effectiveness for this indication.

METHODS

Among patients undergoing ischemic VT ablation with the ThermoCool STSF catheter pooled across two health systems (Mercy Health and Mayo Clinic), the primary safety composite outcome of death, thromboembolic events, and procedural complications within 7 days was compared to a performance goal of 15%, which is twice the expected proportion of the primary composite safety outcome based on prior studies. The exploratory effectiveness outcome of rehospitalization for VT or heart failure or repeat VT ablation at up to 1 year was averaged across health systems among patients treated with the ThermoCool STSF vs. ST catheters.

RESULTS

Seventy total patients received ablation for ischemic VT using the ThermoCool STSF catheter. The primary safety composite outcome occurred in 3/70 (4.3%; 90% CI, 1.2-10.7%) patients, meeting the pre-specified performance goal, p = 0.0045. At 1 year, the effectiveness outcome risk difference (STSF-ST) at Mercy was - 0.4% (90% CI: - 25.2%, 24.3%) and at Mayo Clinic was 12.6% (90% CI: - 13.0%, 38.4%); the average risk difference across both institutions was 5.8% (90% CI: - 12.0, 23.7).

CONCLUSIONS

The ThermoCool STSF catheter was safe and appeared effective for ischemic VT ablation, supporting continued use of the catheter and informing possible FDA label expansion. Health system data hold promise for real-world safety and effectiveness evaluation of cardiovascular devices.

Health care costs of COVID-19 vs influenza and pneumonia

OBJECTIVES

To estimate payments for the treatment of COVID-19 compared with that of influenza or viral pneumonia (IP), from the perspective of the US payer.

STUDY DESIGN

Retrospective cohort analysis.

METHODS

Patients with COVID-19 during the period from October 1, 2020, to February 1, 2021, or IP during the period from October 1, 2018, to February 1, 2019, in the IBM MarketScan databases were identified. The index was defined as the date of the first COVID-19 or IP diagnosis. Patients with COVID-19 were stratified by severity. Variables for all patients included demographics and comorbidities at the time of index and duration of disease. IP and COVID-19 cohorts were matched using propensity scores, and inflation-adjusted all-cause payments (ACP), and disease-specific payments (DSP) for IP vs COVID-19 were estimated using generalized linear models.

RESULTS

Matched cohorts included 6332 Medicare (female, 58.5%; mean [SD] age, 75.3 [7.6] years), and 397,532 commercially insured patients (female, 57.6%; mean [SD] age, 34.7 [16.7] years). ACP and DSP were significantly higher in the COVID-19 cohort vs IP cohort. Payments for severe/critical COVID-19 were significantly greater than those for IP, with adjusted marginal incremental DSP and ACP of $24,852 (95% CI, $21,573-$28,132) and $50,325 (95% CI, $43,932-$56,718), respectively. IP was significantly less expensive than moderate COVID-19 for commercial payers but not Medicare. IP was more expensive than mild COVID-19 for all payers.

CONCLUSIONS

Payments associated with severe/critical COVID-19 significantly exceeded those associated with IP. For Medicare, IP was more expensive than mild or moderate COVID-19. For commercial payers, IP was less expensive than moderate COVID-19 but more expensive than mild COVID-19.

Racial and Health Insurance Differences in Patient Outcomes After Surgical Treatment for Cauda Equina Syndrome: A United States Retrospective Hospital Claims Database Analysis

STUDY DESIGN

Retrospective database evaluation.

OBJECTIVES

To study the association between race, health care insurance, mortality, postoperative visits, and reoperation within a hospital setting in patients with cauda equina syndrome (CES) undergoing surgical intervention.

SUMMARY OF BACKGROUND DATA

CES can lead to permanent neurological deficits if the diagnosis is missed or delayed. Evidence of racial or insurance disparities in CES is sparse.

MATERIALS AND METHODS

Patients with CES undergoing surgery from 2000 to 2021 were identified from the Premier Health care Database. Six-month postoperative visits and 12-month reoperations within the hospital were compared by race ( i.e ., White, Black, or Other [Asian, Hispanic, or other]) and insurance ( i.e. , Commercial, Medicaid, Medicare, or Other) using Cox proportional hazard regressions; covariates were used in the regression models to control for confounding. Likelihood ratio tests were used to compare model fit.

RESULTS

Among 25,024 patients, most were White (76.3%), followed by Other race (15.4% [ 8.8% Asian, 7.3% Hispanic, and 83.9% other]) and Black (8.3%). Models with race and insurance combined provided the best fit for estimating the risk of visits to any setting of care and reoperations. White Medicaid patients had the strongest association with a higher risk of 6-month visits to any setting of care versus White patients with commercial insurance (HR: 1.36 (1.26,1.47)). Being Black with Medicare had a strong association with a higher risk of 12-month reoperations versus White commercial patients (HR: 1.43 (1.10,1.85)). Having Medicaid versus Commercial insurance was strongly associated with a higher risk of complication-related (HR: 1.36 (1.21, 1.52)) and ER visits (HR: 2.26 (2.02,2.51)). Medicaid had a significantly higher risk of mortality compared with Commercial patients (HR: 3.19 (1.41,7.20)).

CONCLUSIONS

Visits to any setting of care, complication-related, ER visits, reoperation, or mortality within the hospital setting after CES surgical treatment varied by race and insurance. Insurance type had a stronger association with the outcomes than race.

LEVEL OF EVIDENCE

Level-III.

Integrating real-world data to assess cardiac ablation device outcomes in a multicenter study using the OMOP common data model for regulatory decisions: implementation and evaluation

The objective of this study is to describe application of the Observational Medical Outcomes Partnership (OMOP) common data model (CDM) to support medical device real-world evaluation in a National Evaluation System for health Technology Coordinating Center (NESTcc) Test-Case involving 2 healthcare systems, Mercy Health and Mayo Clinic. CDM implementation was coordinated across 2 healthcare systems with multiple hospitals to aggregate both medical device data from supply chain databases and patient outcomes and covariates from electronic health record data. Several data quality assurance (QA) analyses were implemented on the OMOP CDM to validate the data extraction, transformation, and load (ETL) process. OMOP CDM-based data of relevant patient encounters were successfully established to support studies for FDA regulatory submissions. QA analyses verified that the data transformation was robust between data sources and OMOP CDM. Our efforts provided useful insights in real-world data integration using OMOP CDM for medical device evaluation coordinated across multiple healthcare systems.

Impact of a digital surgical workflow including Digital Device Briefing Tool on morbidity and mortality in a patient population undergoing primary stapled colorectal anastomosis for benign or malignant colorectal disease: protocol for a multicentre prospective cohort study

INTRODUCTION

With growing emphasis on surgical safety, it appears fundamental to assess the safety of colorectal resection involving primary stapled anastomosis. Surgical stapling devices can considerably foster patient safety in colorectal surgery, but their misuse or malfunction encompass a unique risk of postoperative complications. The Digital Device Briefing Tool (DDBT) is a digital cognitive aid developed to enhance safe use of the Ethicon circular stapling device during colorectal resection. The purpose of this study is to evaluate how a digital operative workflow, including DDBT, compared with routine surgical care, affects morbidity and mortality in patients undergoing left-sided colorectal resection with primary stapled colorectal anastomosis for colorectal cancer or benign disease.

METHODS AND ANALYSIS

A multicentre, prospective cohort study will be conducted at five certified academic colorectal centres in Germany. It compares a non-digital with a Johnson & Johnson digital solution (Surgical Process Institute Deutschland (SPI))-guided operative workflow in patients undergoing left hemicolectomy, sigmoidectomy, anterior rectal resection and Hartmann reversal procedure. The sample size is set at 528 cases in total, divided into 3 groups (a non-digital and two SPI-guided workflow cohorts, with and without DDBT) in a ratio of 1:1:1, with 176 patients each. The primary endpoint is a composite outcome comprising the overall rate of surgical complications, including death, during hospitalisation and within the first 30 days after colorectal resection. Secondary endpoints include operating time, length of hospital stay and 30-day hospital readmission rate.

ETHICS AND DISSEMINATION

This study will be performed in line with the Declaration of Helsinki. The ethics committee of the Charité-University Medicine Berlin, Germany, approved the study (No: 22-0277-EA2/060/22). Study Investigators will obtain written informed consent from each patient before a patient may participate in this study. The study results will be submitted to an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

DRKS00029682.

Comparison of Clinical Outcomes of Gripping Surface Technology Staple Reloads versus Standard Staple Reloads Used with Manual Linear Surgical Staplers

PURPOSE

Linear surgical staplers reduce rates of surgical adverse events (bleeding, leaks, infections) compared to manual sutures thereby reducing patient risks, surgeon workflow disruption, and healthcare costs. However, further improvements are needed. Ethicon Gripping Surface Technology (GST) reloads, tested and approved by regulatory authorities in combination with powered staplers, may reduce surgical risks through improved tissue grip. While manual staplers are used in some regions due to affordability, clinical data on GST reloads used with manual staplers are unavailable. This study compared surgical adverse event rates of manual staplers with GST vs standard reloads. These data may be used for label changes in China and Latin America.

PATIENTS AND METHODS

Patients undergoing general or thoracic surgery between October 1, 2015 and August 31, 2021 using ECHELON FLEX™ manual staplers with GST or standard reloads were identified from the Premier Healthcare Database. GST reloads were compared to standard reloads for non-inferiority in bleeding and anastomotic leak for general surgery. Secondary outcomes included sepsis for general surgery, and bleeding and prolonged air leak for thoracic surgery. Covariate balancing was performed using stable balancing weights.

RESULTS

The general and thoracic surgery cohorts contained 4571 (GST: 2780; standard: 1791) and 814 (GST: 514; standard: 300) patients, respectively. GST reloads were non-inferior to standard reloads for bleeding and anastomotic leak (adjusted cumulative incidence ratio: 1.02 [90% CI: 0.71, 1.45] and 1.03 [90% CI: 0.72, 1.46], respectively) for general surgery. Compared with standard reloads, GST reloads had a similar incidence of sepsis (2.2% vs 2.1%) for general surgery and lower incidences of bleeding (9.5% vs 16.0%) and prolonged air leak (12.6% vs 14.0%,) for thoracic surgery.

CONCLUSION

GST reloads, compared to standard reloads, used with ECHELON FLEX™ manual staplers had comparable perioperative bleeding and anastomotic leak for general surgery, and lower incidences of safety events for thoracic surgery.

Safety and Effectiveness of a Catheter With Contact Force and 6-Hole Irrigation for Ablation of Persistent Atrial Fibrillation in Routine Clinical Practice

IMPORTANCE

The ThermoCool SmartTouch catheter (ablation catheter with contact force and 6-hole irrigation [CF-I6]) is approved by the US Food and Drug Administration (FDA) for paroxysmal atrial fibrillation (AF) ablation and used in routine clinical practice for persistent AF ablation, although clinical outcomes for this indication are unknown. There is a need to understand whether data from routine clinical practice can be used to conduct regulatory-grade evaluations and support label expansions.

OBJECTIVE

To use health system data to compare the safety and effectiveness of the CF-I6 catheter for persistent AF ablation with the ThermoCool SmartTouch SurroundFlow catheter (ablation catheter with contact force and 56-hole irrigation [CF-I56]), which is approved by the FDA for this indication.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, comparative-effectiveness cohort study included patients undergoing catheter ablation for persistent AF at Mercy Health or Mayo Clinic from January 1, 2014, to April 30, 2021, with up to a 1-year follow-up using electronic health record data.

EXPOSURES

Use of the CF-I6 or CF-I56 catheter.

MAIN OUTCOMES AND MEASURES

The primary safety outcome was a composite of death, thromboembolic events, and procedural complications within 7 to 90 days. The exploratory effectiveness outcome was a composite of AF-related hospitalization events after a 90-day blanking period. Propensity score weighting was used to balance baseline covariates. Risk differences were estimated between catheter groups and averaged across the 2 health care systems, testing for noninferiority of the CF-I6 vs the CF-I56 catheter with respect to the safety outcome using 2-sided 90% CIs.

RESULTS

Overall, 1450 patients (1034 [71.3%] male; 1397 [96.3%] White) underwent catheter ablation for persistent AF, including 949 at Mercy Health (186 CF-I6 and 763 CF-I56; mean [SD] age, 64.9 [9.2] years) and 501 at Mayo Clinic (337 CF-I6 and 164 CF-I56; mean [SD] age, 63.7 [9.5] years). A total of 798 (55.0%) had been treated with class I or III antiarrhythmic drugs before ablation. The safety outcome (CF-I6 - CF-I56) was similar at both Mercy Health (1.3%; 90% CI, -2.1% to 4.6%) and Mayo Clinic (-3.8%; 90% CI, -11.4% to 3.7%); the mean difference was noninferior, with a mean of 0.5% (90% CI, -2.6% to 3.5%; P < .001). The effectiveness was similar at 12 months between the 2 catheter groups (mean risk difference, -1.8%; 90% CI, -7.3% to 3.7%).

CONCLUSIONS AND RELEVANCE

In this cohort study, the CF-I6 catheter met the prespecified noninferiority safety criterion for persistent AF ablation compared with the CF-I56 catheter, and effectiveness was similar. This study demonstrates the ability of electronic health care system data to enable safety and effectiveness evaluations of medical devices.

Site-specific cancer risk following cobalt exposure via orthopedic implants or in occupational settings: A systematic review and meta-analysis

In 2020, the European Commission up-classified metal cobalt as Class 1B Carcinogen (presumed to have carcinogenic potential) based primarily on data from rodent inhalation carcinogenicity studies. This up-classification requires an assessment under the Medical Device Regulations of cobalt cancer risk from medical devices. We performed a systematic review and meta-analysis to evaluate site-specific cancer risks with cobalt exposure from either total joint replacement (TJR) or occupational exposure (OC). Results were stratified by exposure type (OC or TJR), exposure level (metal-on-metal (MoM) or non-MoM), follow-up duration (latency period: <5, 5-10 or >10 years), and cancer incidence or mortality (detection bias assessment). From 30 studies (653,104 subjects, average 14.5 years follow-up), the association between TJR/OC and cancer risk was null for 22 of 27 cancer sites, negative for 3 sites, and positive for prostate cancer and myeloma. Significant heterogeneity and large estimate ranges were observed for many cancer sites. No significant increase in estimates was observed by exposure level or follow-up duration. The current evidence, including weak associations, heterogeneity across studies and no increased association with exposure level or follow-up duration, is insufficient to conclude that there exists an increased risk for people exposed to cobalt in TJR/OC of developing site-specific cancers.

Challenges of evaluating and modelling vaccination in emerging infectious diseases

Outbreaks of emerging pathogens pose unique methodological and practical challenges for the design, implementation, and evaluation of vaccine efficacy trials. Lessons learned from COVID-19 highlight the need for innovative and flexible study design and application to quickly identify promising candidate vaccines. Trial design strategies should be tailored to the dynamics of the specific pathogen, location of the outbreak, and vaccine prototypes, within the regional socioeconomic constraints. Mathematical and statistical models can assist investigators in designing infectious disease clinical trials. We introduce key challenges for planning, evaluating, and modelling vaccine efficacy trials for emerging pathogens.

An integrated benefit-risk assessment of cobalt-containing alloys used in medical devices: Implications for regulatory requirements in the European Union

In 2017, the European Union (EU) Committee for Risk Assessment (RAC) recommended the classification of metallic cobalt (Co) as Category 1B with respect to its carcinogenic and reproductive hazard potential and Category 2 for mutagenicity but did not evaluate the relevance of these classifications for patients exposed to Co-containing alloys (CoCA) used in medical devices. CoCA are inherently different materials from Co metal from a toxicological perspective and thus require a separate assessment. CoCA are biocompatible materials with a unique combination of properties including strength, durability, and a long history of safe use that make them uniquely suited for use in a wide-range of medical devices. Assessments were performed on relevant preclinical and clinical carcinogenicity and reproductive toxicity data for Co and CoCA to meet the requirements under the EU Medical Device Regulation triggered by the ECHA re-classification (adopted in October 2019 under the 14th Adaptation to Technical Progress to CLP) and to address their relevance to patient safety. The objective of this review is to present an integrated overview of these assessments, a benefit-risk assessment and an examination of potential alternative materials. The data support the conclusion that the exposure to CoCA in medical devices via clinically relevant routes does not represent a hazard for carcinogenicity or reproductive toxicity. Additionally, the risk for the adverse effects that are known to occur with elevated Co concentrations (e.g., cardiomyopathy) are very low for CoCA implant devices (infrequent reports often reflecting a unique catastrophic failure event out of millions of patients) and negligible for CoCA non-implant devices (not measurable/no case reports). In conclusion, the favorable benefit-risk profile also in relation to possible alternatives presented herein strongly support continued use of CoCA in medical devices.

Measuring problem prescription opioid use among patients receiving long-term opioid analgesic treatment: development and evaluation of an algorithm for use in EHR and claims data

Objective

Opioid surveillance in response to the opioid epidemic will benefit from scalable, automated algorithms for identifying patients with clinically documented signs of problem prescription opioid use. Existing algorithms lack accuracy. We sought to develop a high-sensitivity, high-specificity classification algorithm based on widely available structured health data to identify patients receiving chronic extended-release/long-acting (ER/LA) therapy with evidence of problem use to support subsequent epidemiologic investigations.

Methods

Outpatient medical records of a probability sample of 2,000 Kaiser Permanente Washington patients receiving ≥60 days’ supply of ER/LA opioids in a 90-day period from 1 January 2006 to 30 June 2015 were manually reviewed to determine the presence of clinically documented signs of problem use and used as a reference standard for algorithm development. Using 1,400 patients as training data, we constructed candidate predictors from demographic, enrollment, encounter, diagnosis, procedure, and medication data extracted from medical claims records or the equivalent from electronic health record (EHR) systems, and we used adaptive least absolute shrinkage and selection operator (LASSO) regression to develop a model. We evaluated this model in a comparable 600-patient validation set. We compared this model to ICD-9 diagnostic codes for opioid abuse, dependence, and poisoning. This study was registered with ClinicalTrials.gov as study NCT02667262 on 28 January 2016.

Results

We operationalized 1,126 potential predictors characterizing patient demographics, procedures, diagnoses, timing, dose, and location of medication dispensing. The final model incorporating 53 predictors had a sensitivity of 0.582 at positive predictive value (PPV) of 0.572. ICD-9 codes for opioid abuse, dependence, and poisoning had a sensitivity of 0.390 at PPV of 0.599 in the same cohort.

Conclusions

Scalable methods using widely available structured EHR/claims data to accurately identify problem opioid use among patients receiving long-term ER/LA therapy were unsuccessful. This approach may be useful for identifying patients needing clinical evaluation.

Development of an algorithm to identify inpatient opioid-related overdoses and oversedation using electronic data

PURPOSE

To facilitate surveillance and evaluate interventions addressing opioid-related overdoses, algorithms are needed for use in large health care databases to identify and differentiate community-occurring opioid-related overdoses from inpatient-occurring opioid-related overdose/oversedation.

METHODS

Data were from Kaiser Permanente Northwest (KPNW), a large integrated health plan. We iteratively developed and evaluated an algorithm for electronically identifying inpatient overdose/oversedation in KPNW hospitals from 1 January 2008 to 31 December 2014. Chart audits assessed accuracy; data sources included administrative and clinical records.

RESULTS

The best-performing algorithm used these rules: (1) Include events with opioids administered in an inpatient setting (including emergency department/urgent care) followed by naloxone administration within 275 hours of continuous inpatient stay; (2) exclude events with electroconvulsive therapy procedure codes; and (3) exclude events in which an opioid was administered prior to hospital discharge and followed by readmission with subsequent naloxone administration. Using this algorithm, we identified 870 suspect inpatient overdose/oversedation events and chart audited a random sample of 235. Of the random sample, 185 (78.7%) were deemed overdoses/oversedation, 37 (15.5%) were not, and 13 (5.5%) were possible cases. The number of hours between time of opioid and naloxone administration did not affect algorithm accuracy. When "possible" overdoses/oversedations were included with confirmed events, overall positive predictive value (PPV) was very good (PPV = 84.0%). Additionally, PPV was reasonable when evaluated specifically for hospital stays with emergency/urgent care admissions (PPV = 77.0%) and excellent for elective surgery admissions (PPV = 97.0%).

CONCLUSIONS

Algorithm performance was reasonable for identifying inpatient overdose/oversedation with best performance among elective surgery patients.

Identifying and classifying opioid-related overdoses: A validation study

PURPOSE

The study aims to develop and validate algorithms to identify and classify opioid overdoses using claims and other coded data, and clinical text extracted from electronic health records using natural language processing (NLP).

METHODS

Primary data were derived from Kaiser Permanente Northwest (2008-2014), an integrated health care system (~n > 475 000 unique individuals per year). Data included International Classification of Diseases, Ninth Revision (ICD-9) codes for nonfatal diagnoses, International Classification of Diseases, Tenth Revision (ICD-10) codes for fatal events, clinical notes, and prescription medication records. We assessed sensitivity, specificity, positive predictive value, and negative predictive value for algorithms relative to medical chart review and conducted assessments of algorithm portability in Kaiser Permanente Washington, Tennessee State Medicaid, and Optum.

RESULTS

Code-based algorithm performance was excellent for opioid-related overdoses (sensitivity = 97.2%, specificity = 84.6%) and classification of heroin-involved overdoses (sensitivity = 91.8%, specificity = 99.0%). Performance was acceptable for code-based suicide/suicide attempt classifications (sensitivity = 70.7%, specificity = 90.5%); sensitivity improved with NLP (sensitivity = 78.7%, specificity = 91.0%). Performance was acceptable for the code-based substance abuse-involved classification (sensitivity = 75.3%, specificity = 79.5%); sensitivity improved with the NLP-enhanced algorithm (sensitivity = 80.5%, specificity = 76.3%). The opioid-related overdose algorithm performed well across portability assessment sites, with sensitivity greater than 96% and specificity greater than 84%. Cross-site sensitivity for heroin-involved overdose was greater than 87%, specificity greater than or equal to 99%.

CONCLUSIONS

Code-based algorithms developed to detect opioid-related overdoses and classify them according to heroin involvement perform well. Algorithms for classifying suicides/attempts and abuse-related opioid overdoses perform adequately for use for research, particularly given the complexity of classifying such overdoses. The NLP-enhanced algorithms for suicides/suicide attempts and abuse-related overdoses perform significantly better than code-based algorithms and are appropriate for use in settings that have data and capacity to use NLP.

Using natural language processing of clinical text to enhance identification of opioid-related overdoses in electronic health records data

Purpose

To enhance automated methods for accurately identifying opioid‐related overdoses and classifying types of overdose using electronic health record (EHR) databases.

Methods

We developed a natural language processing (NLP) software application to code clinical text documentation of overdose, including identification of intention for self‐harm, substances involved, substance abuse, and error in medication usage. Using datasets balanced with cases of suspected overdose and records of individuals at elevated risk for overdose, we developed and validated the application using Kaiser Permanente Northwest data, then tested portability of the application using Kaiser Permanente Washington data. Datasets were chart‐reviewed to provide a gold standard for comparison and evaluation of the automated method.

Results

The method performed well in identifying overdose (sensitivity = 0.80, specificity = 0.93), intentional overdose (sensitivity = 0.81, specificity = 0.98), and involvement of opioids (excluding heroin, sensitivity = 0.72, specificity = 0.96) and heroin (sensitivity = 0.84, specificity = 1.0). The method performed poorly at identifying adverse drug reactions and overdose due to patient error and fairly at identifying substance abuse in opioid‐related unintentional overdose (sensitivity = 0.67, specificity = 0.96). Evaluation using validation datasets yielded significant reductions, in specificity and negative predictive values only, for many classifications mentioned above. However, these measures remained above 0.80, thus, performance observed during development was largely maintained during validation. Similar results were obtained when evaluating portability, although there was a significant reduction in sensitivity for unintentional overdose that was attributed to missing text clinical notes in the database.

Conclusions

Methods that process text clinical notes show promise for improving accuracy and fidelity at identifying and classifying overdoses according to type using EHR data.

Conditional power for assessing population interventions

AIM

To calculate conditional power in comparative two-period studies with previously observed baseline data.

METHOD

Isolate the variability attributable to the yet-to-observed data and modify the standard power formulae.

RESULTS

For illustration, we examine rates of opioid overdose before and after a reformulation of one opioid product. The null hypothesis posited no impact of the reformulation, alternative hypotheses posited possible impacts, and ancillary hypotheses posited different secular pre-post changes directly observable in comparators. Conditional power varied with the size of the comparator population and with the assumed pre-post change for the comparator.

CONCLUSION

Pre-post designs can be initiated after the baseline period is over. Power calculations that are conditioned on observed baseline data account differently for variability in the baseline and follow-up periods.

Incidence of nonmedical use of OxyContin and other prescription opioid pain relievers before and after the introduction of OxyContin with abuse deterrent properties

OBJECTIVES

There is an epidemic of nonmedical and extra-medical use opioid abuse, addiction, and overdose. Extended-release oxycodone (OxyContin®), a prescription opioid pain reliever, was reformulated in 2010 to deter its abuse. The aim of this study was to assess changes in the onset of abuse of OxyContin and other opioids among young people and adults after reformulation of OxyContin with abuse-deterrent properties.

METHODS

The study population was U.S. residents ≥ 12 years sampled in National Surveys on Drug Use and Health (NSDUH), 2004 to 2015, with subsample of 12-21-year-olds. Nonmedical and extra-medical use is the NSDUH proxy for abuse. Confidential audio-computer-assisted self-interviews were assessed. Age-specific incidence of nonmedical and extra-medical use of OxyContin and other prescription opioids were estimated year by year. Interrupted-time-series and age-period-cohort analyses were analyzed.

RESULTS

Interrupted-time-series analysis showed a lower incidence of OxyContin nonmedical and extra-medical use after 2010 reformulation compared to the counterfactual predicted by the trend before 2010. No such difference was seen for other prescription opioids for all ages, although a lower incidence was also observed for other prescription opioids among 12-21-year-olds. Among 12-21-year-olds, a robustly lower incidence was found in 2012 compared to 2010 for OxyContin after holding constant age and cohort effects, whereas no robust difference was observed for other prescription opioids. The results showed 137,500 fewer newly incident cases of OxyContin nonmedical and extra-medical use per year.

CONCLUSIONS

This study provides evidence supporting the role of OxyContin reformulation in the reduction of onset of OxyContin nonmedical and extra-medical use.

ER/LA Opioid Analgesics REMS: Overview of Ongoing Assessments of Its Progress and Its Impact on Health Outcomes

Objective. Opioid abuse is a serious public health concern. In response, the Food and Drug Administration (FDA) determined that a risk evaluation and mitigation strategy (REMS) for extended-release and long-acting (ER/LA) opioids was necessary to ensure that the benefits of these analgesics continue to outweigh the risks. Key components of the REMS are training for prescribers through accredited continuing education (CE), and providing patient educational materials.

Methods. The impact of this REMS has been assessed using diverse metrics including evaluation of prescriber and patient understanding of the risks associated with opioids; patient receipt and comprehension of the medication guide and patient counseling document; patient satisfaction with access to opioids; drug utilization and changes in prescribing patterns; and surveillance of ER/LA opioid misuse, abuse, overdose, addiction, and death.

Results and Conclusions. The results of these assessments indicate that the increasing rates of opioid abuse, addiction, overdose, and death observed prior to implementation of the REMS have since leveled off or started to decline. However, these benefits cannot be attributed solely to the ER/LA opioid analgesics REMS since many other initiatives to prevent abuse occurred contemporaneously. These improvements occurred while preserving patient access to opioids as a large majority of patients surveyed expressed satisfaction with their access to opioids.

Assessing the accuracy of opioid overdose and poisoning codes in diagnostic information from electronic health records, claims data, and death records

PURPOSE

The purpose of this study is to assess positive predictive value (PPV), relative to medical chart review, of International Classification of Diseases (ICD)-9/10 diagnostic codes for identifying opioid overdoses and poisonings.

METHODS

Data were obtained from Kaiser Permanente Northwest and Northern California. Diagnostic data from electronic health records, submitted claims, and state death records from Oregon, Washington, and California were linked. Individual opioid-related poisoning codes (e.g., 965.xx and X42), and adverse effects of opioids codes (e.g., E935.xx) combined with diagnoses possibly indicative of overdoses (e.g., respiratory depression), were evaluated by comparison with chart audits.

RESULTS

Opioid adverse effects codes had low PPV to detect overdoses (13.4%) as assessed in 127 charts and were not pursued. Instead, opioid poisoning codes were assessed in 2100 individuals who had those codes present in electronic health records in the period between the years 2008 and 2012. Of these, 10/2100 had no available information and 241/2100 were excluded potentially as anesthesia-related. Among the 1849 remaining individuals with opioid poisoning codes, 1495 events were accurately identified as opioid overdoses; 69 were miscodes or misidentified, and 285 were opioid adverse effects, not overdoses. Thus, PPV was 81%. Opioid adverse effects or overdoses were accurately identified in 1780 of 1849 events (96.3%).

CONCLUSIONS

Opioid poisoning codes have a predictive value of 81% to identify opioid overdoses, suggesting ICD opioid poisoning codes can be used to monitor overdose rates and evaluate interventions to reduce overdose. Further research to assess sensitivity, specificity, and negative predictive value are ongoing. Copyright © 2017 John Wiley & Sons, Ltd.

Understanding opioid overdose characteristics involving prescription and illicit opioids: A mixed methods analysis

BACKGROUND

Opioid abuse and misuse are significant public health issues. The CDC estimated 72% of pharmaceutical-related overdose deaths in the US in 2012 involved opioids. While studies of opioid overdoses have identified sociodemographic characteristics, agents used, administration routes, and medication sources associated with overdoses, we know less about the context and life circumstances of the people who experience these events.

METHODS

We analyzed interviews (n=87) with survivors of opioid overdoses or family members of decedents. Individuals experiencing overdoses were members of a large integrated health system. Using ICD codes for opioid overdoses and poisonings, we identified participants from five purposefully derived pools of health-plan members who had: 1) prescriptions for OxyContin(®) or single-ingredient sustained-release oxycodone, 2) oxycodone single-ingredient immediate release, 3) other long-acting opioids, 4) other short-acting opioids, or 5) no active opioid prescriptions.

RESULTS

Individuals who experienced opioid overdoses abused and misused multiple medications/drugs; experienced dose-related miscommunications or medication-taking errors; had mental health and/or substance use conditions; reported chronic pain; or had unstable resources or family/social support. Many had combinations of these risks. Most events involved polysubstance use, often including benzodiazepines. Accidental overdoses were commonly the result of abuse or misuse, some in response to inadequately treated chronic pain or, less commonly, medication-related mistakes. Suicide attempts were frequently triggered by consecutive negative life events.

CONCLUSIONS

To identify people at greater risk of opioid overdose, efforts should focus on screening for prescribed and illicit polysubstance use, impaired cognition, and changes in life circumstances, psychosocial risks/supports, and pain control.

Decreased diversion by doctor-shopping for a reformulated extended release oxycodone product (OxyContin)

BACKGROUND

Doctor-shopping (obtaining prescriptions from multiple prescribers/pharmacies) for opioid analgesics produces a supply for diversion and abuse, and represents a major public health issue.

METHODS

An open cohort study assessed changes in doctor-shopping in the U.S. for a brand extended release (ER) oxycodone product (OxyContin) and comparator opioids before (July, 2009 to June, 2010) versus after (January, 2011 to June, 2013) introduction of reformulated brand ER oxycodone with abuse-deterrent properties, using IMS LRx longitudinal data covering >150 million patients and 65% of retail U.S. prescriptions.

RESULTS

After its reformulation, the rate of doctor-shopping decreased 50% (for 2+ prescribers/3+ pharmacies) for brand ER oxycodone, but not for comparators. The largest decreases in rates occurred among young adults (73%), those paying with cash (61%) and those receiving the highest available dose (62%), with a 90% decrease when stratifying by all three characteristics. The magnitude of doctor-shopping reductions increased with increasing number of prescribers/pharmacies (e.g., 75% reduction for ≥2 prescribers/≥4 pharmacies).

CONCLUSIONS

The rate of doctor-shopping for brand ER oxycodone decreased substantially after its reformulation, which did not occur for other prescription opioids. The largest reductions in doctor-shopping occurred with characteristics associated with higher abuse risk such as youth, cash payment and high dose, and with more specific thresholds of doctor-shopping. A higher prescriber and/or pharmacy threshold also increased the magnitude of the decrease, suggesting that it better captured the effect of the reformulation on actual doctor-shoppers.

The effect of an abuse-deterrent opioid formulation (OxyContin) on opioid abuse-related outcomes in the postmarketing setting

An extended‐release opioid analgesic (OxyContin, OC) was reformulated with abuse‐deterrent properties to deter abuse. This report examines changes in abuse through oral and nonoral routes, doctor‐shopping, and fatalities in 10 studies 3.5 years after reformulation. Changes in OC abuse from 1 year before to 3 years after OC reformulation were calculated, adjusted for prescription changes. Abuse of OC decreased 48% in national poison center surveillance systems, decreased 32% in a national drug treatment system, and decreased 27% among individuals prescribed OC in claims databases. Doctor‐shopping for OC decreased 50%. Overdose fatalities reported to the manufacturer decreased 65%. Abuse of other opioids without abuse‐deterrent properties decreased 2 years later than OC and with less magnitude, suggesting OC decreases were not due to broader opioid interventions. Consistent with the formulation, decreases were larger for nonoral than oral abuse. Abuse‐deterrent opioids may mitigate abuse and overdose risks among chronic pain patients.

Protocol: changes in rates of opioid overdose and poisoning events in an integrated health system following the introduction of a formulation of OxyContin® with abuse-deterrent properties

Background

Addiction, overdoses and deaths resulting from prescription opioids have increased dramatically over the last decade. In response, several manufacturers have developed formulations of opioids with abuse-deterrent properties. For many of these products, the Food and Drug Administration (FDA) recognized the formulation with labeling claims and mandated post-marketing studies to assess the abuse-deterrent effects. In response, we assess differences in rates of opioid-related overdoses and poisonings prior to and following the introduction of a formulation of OxyContin® with abuse-deterrent properties.

Methods/Design

To assess effects of this formulation, electronic medical record (EMR) data from Kaiser Permanente Northwest (KPNW) and Kaiser Permanente Northern California (KPNC) are linked to state death data and compared to chart audits. Overdose and poisoning events will be categorized by intentionality and number of agents involved, including illicit drugs and alcohol. Using 6-month intervals over a 10-year period, trends will be compared in rates of opioid-related overdoses and poisoning events associated with OxyContin® to rates of events associated with other oxycodone and opioid formulations. Qualitative interviews with patients and relatives of deceased patients will be conducted to capture circumstances surrounding events.

Discussion

This study assesses and tracks changes in opioid-related overdoses and poisoning events prior to and following the introduction of OxyContin® with abuse-deterrent properties. Public health significance is high because these medications are designed to reduce abuse-related behaviors that lead to important adverse outcomes, including overdoses and deaths.

Electronic supplementary material

The online version of this article (doi:10.1186/s40360-016-0064-y) contains supplementary material, which is available to authorized users.

Impact of vaccination on the epidemiology of varicella: 1995-2009

BACKGROUND

When varicella vaccine was licensed in the United States in 1995, there were concerns that childhood vaccination might increase the number of adolescents susceptible to varicella and shift disease toward older age groups where it can be more severe.

METHODS

We conducted a series of 5 cross-sectional studies in 1994 to 1995 (prevaccine), 2000, 2003, 2006, and 2009 in Kaiser Permanente of Northern California to assess changes in varicella epidemiology in children and adolescents, as well as changes in varicella hospitalization in people of all ages. For each study, information on varicella history and varicella occurrence during the past year was obtained by telephone survey from a sample of ∼8000 members 5 to 19 years old; varicella hospitalization rates were calculated for the entire membership.

RESULTS

Between 1995 and 2009, the overall incidence of varicella in 5- to 19-year-olds decreased from 25.8 to 1.3 per 1000 person-years, a ∼90% to 95% decline in the various age categories (5-9, 10-14, and 15-19 years of age). The proportion of varicella-susceptible children and adolescents also decreased in all age groups, including in 15- to 19-year-olds (from 15.6% in 1995 to 7.6% in 2009). From 1994 to 2009, age-adjusted varicella hospitalization rates in the general member population decreased from 2.13 to 0.25 per 100,000, a ∼90% decline.

CONCLUSIONS

In the 15 years after the introduction of varicella vaccine, a major reduction in varicella incidence and hospitalization was observed with no evidence of a shift in the burden of varicella to older age groups.

Reductions in reported deaths following the introduction of extended-release oxycodone (OxyContin) with an abuse-deterrent formulation

Purpose

Abuse of opioid analgesics for their psychoactive effects is associated with a large number of fatalities. The effect of making opioid tablets harder to crush/dissolve on opioid-related fatalities has not been assessed. The objective of this study was to assess the impact of introducing extended-release oxycodone (ERO [OxyContin®]) tablets containing physicochemical barriers to crushing/dissolving (reformulated ERO) on deaths reported to the manufacturer.

Methods

All spontaneous adverse event reports of death in the US reported to the manufacturer between 3Q2009 and 3Q2013 involving ERO were used. The mean numbers of deaths/quarter in the 3 years after reformulated ERO introduction were compared with the year before. Changes in the slope of trends in deaths were assessed using spline regression. Comparison groups consisted of non-fatal reports involving ERO and fatality reports involving ER morphine.

Results

Reports of death decreased 82% (95% CI: −89, −73) from the year before to the third year after (131 to 23 deaths per year) reformulation; overdose death reports decreased 87% (95% CI: −93, −78) and overdose deaths with mention of abuse-related behavior decreased 86% (95% CI:−92, −75). In contrast, non-fatal ERO reports did not decrease post-reformulation, and reported ER morphine fatalities remained unchanged. The ratio of ERO fatalities to all oxycodone fatalities decreased from 21% to 8% in the year pre-reformulation to the second year post-reformulation.

Conclusions

These findings, when considered in the context of previously published studies using other surveillance systems, suggest that the abuse-deterrent characteristics of reformulated ERO have decreased the fatalities associated with its misuse/abuse. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.

Monitoring of internet forums to evaluate reactions to the introduction of reformulated OxyContin to deter abuse

Background

Reformulating opioid analgesics to deter abuse is one approach toward improving their benefit-risk balance. To assess sentiment and attempts to defeat these products among difficult-to-reach populations of prescription drug abusers, evaluation of posts on Internet forums regarding reformulated products may be useful. A reformulated version of OxyContin (extended-release oxycodone) with physicochemical properties to deter abuse presented an opportunity to evaluate posts about the reformulation in online discussions.

Objective

The objective of this study was to use messages on Internet forums to evaluate reactions to the introduction of reformulated OxyContin and to identify methods aimed to defeat the abuse-deterrent properties of the product.

Methods

Posts collected from 7 forums between January 1, 2008 and September 30, 2013 were evaluated before and after the introduction of reformulated OxyContin on August 9, 2010. A quantitative evaluation of discussion levels across the study period and a qualitative coding of post content for OxyContin and 2 comparators for the 26 month period before and after OxyContin reformulation were conducted. Product endorsement was estimated for each product before and after reformulation as the ratio of endorsing-to-discouraging posts (ERo). Post-to-preintroduction period changes in ERos (ie, ratio of ERos) for each product were also calculated. Additionally, post content related to recipes for defeating reformulated OxyContin were evaluated from August 9, 2010 through September 2013.

Results

Over the study period, 45,936 posts related to OxyContin, 18,685 to Vicodin (hydrocodone), and 23,863 to Dilaudid (hydromorphone) were identified. The proportion of OxyContin-related posts fluctuated between 6.35 and 8.25 posts per 1000 posts before the reformulation, increased to 10.76 in Q3 2010 when reformulated OxyContin was introduced, and decreased from 9.14 in Q4 2010 to 3.46 in Q3 2013 in the period following the reformulation. The sentiment profile for OxyContin changed following reformulation; the post-to-preintroduction change in the ERo indicated reformulated OxyContin was discouraged significantly more than the original formulation (ratio of ERos=0.43, P<.001). A total of 37 recipes for circumventing the abuse-deterrent characteristics of reformulated OxyContin were observed; 32 were deemed feasible (ie, able to abuse). The frequency of posts reporting abuse of reformulated OxyContin via these recipes was low and decreased over time. Among the 5677 posts mentioning reformulated OxyContin, 825 posts discussed recipes and 498 reported abuse of reformulated OxyContin by such recipes (41 reported injecting and 128 reported snorting).

Conclusions

After introduction of physicochemical properties to deter abuse, changes in discussion of OxyContin on forums occurred reflected by a reduction in discussion levels and endorsing content. Despite discussion of recipes, there is a relatively small proportion of reported abuse of reformulated OxyContin via recipes, particularly by injecting or snorting routes. Analysis of Internet discussion is a valuable tool for monitoring the impact of abuse-deterrent formulations.

Changes in oxycodone and heroin exposures in the National Poison Data System after introduction of extended-release oxycodone with abuse-deterrent characteristics

PURPOSE

Abuse and misuse of prescription opioids are serious public health problems. Abuse-deterrent formulations are an intervention to balance risk mitigation with appropriate patient access. This study evaluated the effects of physicochemical barriers to crushing and dissolving on safety outcomes associated with extended-release oxycodone (ERO) tablets (OxyContin) using a national surveillance system of poison centers. Other single-entity (SE) oxycodone tablets and heroin were used as comparators and to assess substitution effects.

METHODS

The National Poison Data System covering all US poison centers was used to measure changes in exposures in the year before versus the 2 years after introduction of reformulated ERO (7/2009-6/2010 vs 9/2010-9/2012). Outcomes included abuse, therapeutic errors affecting patients, and accidental exposures.

RESULTS

After ERO reformulation, abuse exposures decreased 36% for ERO, increased 20% for other SE oxycodone, and increased 42% for heroin. Therapeutic errors affecting patients decreased 20% for ERO and increased 19% for other SE oxycodone. Accidental exposures decreased 39% for ERO, increased 21% for heroin, and remained unchanged for other SE oxycodone. During the study period, other interventions to reduce opioid abuse occurred, for example, educational and prescription monitoring programs. However, these have shown small effects and do not explain a drop for ERO exposures but not for other opioids.

CONCLUSIONS

After ERO reformulation, calls to poison centers involving abuse, therapeutic errors affecting patients, and accidental exposures decreased for ERO, but not for comparator opioids. Abuse-deterrent formulations of opioid analgesics can reduce abuse, but switching to other accessible non abuse-deterrent opioids might occur.

Reduced abuse, therapeutic errors, and diversion following reformulation of extended-release oxycodone in 2010

This study evaluated changes in abuse exposures, therapeutic error exposures, and diversion into illegal markets associated with brand extended-release oxycodone (ERO) following introduction of reformulated ERO. Original ERO and reformulated ERO street prices also were compared. Data from the Poison Center and Drug Diversion programs of the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS) System were used. Quarterly rates 2 years prior to introduction of reformulated ERO (October 2008 through September 2010) were compared to quarterly rates after introduction (October 2010 through March 2012) using negative binomial regression. Street prices were compared using a mixed effects linear regression model. Following reformulated ERO introduction, poison center ERO abuse exposures declined 38% (95% confidence interval [CI]: 31-45) per population and 32% (95% CI: 24-39) per unique recipients of dispensed drug. Therapeutic error exposures declined 24% (95% CI: 15-31) per population and 15% (95% CI: 6-24) per unique recipients of dispensed drug. Diversion reports declined 53% (95% CI: 41-63) per population and 50% (95% CI: 39-59) per unique recipients of dispensed drug. Declines exceeded those observed for other prescription opioids in aggregate. After its introduction, the street price of reformulated ERO was significantly lower than original ERO.

PERSPECTIVE

This article indicates that the abuse, therapeutic errors, and diversion of ERO declined following the introduction of a tamper-resistant reformulation of the product. Reformulating abused prescription opioids to include tamper-resistant properties may be an effective approach to reduce abuse of such products.

Long-term effectiveness of varicella vaccine: a 14-Year, prospective cohort study

BACKGROUND

Varicella vaccine was licensed in the United States in 1995 for individuals ≥12 months of age. A second dose was recommended in the United States in June 2006. Varicella incidence and vaccine effectiveness were assessed in a 14-year prospective study conducted at Kaiser Permanente Northern California.

METHODS

A total of 7585 children vaccinated with varicella vaccine in their second year of life in 1995 were followed up prospectively for breakthrough varicella and herpes zoster (HZ) through 2009. A total of 2826 of these children received a second dose in 2006-2009. Incidences of varicella and HZ were estimated and compared with prevaccine era rates.

RESULTS

In this cohort of vaccinated children, the average incidence of varicella was 15.9 per 1000 person-years, nine- to tenfold lower than in the prevaccine era. Vaccine effectiveness at the end of the study period was 90%, with no indication of waning over time. Most cases of varicella were mild and occurred early after vaccination. No child developed varicella after a second dose. HZ cases were mild, and rates were lower in the cohort of vaccinated children than in unvaccinated children during the prevaccine era (relative risk: 0.61 [95% confidence interval: 0.43-0.89]).

CONCLUSIONS

This study confirmed that varicella vaccine is effective at preventing chicken pox, with no waning noted over a 14-year period. One dose provided excellent protection against moderate to severe disease, and most cases occurred shortly after the cohort was vaccinated. The study data also suggest that varicella vaccination may reduce the risks of HZ in vaccinated children.

Abuse rates and routes of administration of reformulated extended-release oxycodone: initial findings from a sentinel surveillance sample of individuals assessed for substance abuse treatment

Oxycodone hydrochloride controlled-release, also known as extended-release oxycodone (ER oxycodone), was reformulated with physicochemical barriers to crushing and dissolving intended to reduce abuse through nonoral routes of administration (ROAs) that require tampering (eg, injecting and snorting). Manufacturer shipments of original ER oxycodone (OC) stopped on August 5, 2010, and reformulated ER oxycodone (ORF) shipments started August 9, 2010. A sentinel surveillance sample of 140,496 individuals assessed for substance abuse treatment at 357 U.S. centers between June 1, 2009, and March 31, 2012, was examined for prevalence and prescription-adjusted prevalence rates of past-30-day abuse via any route, as well as abuse through oral, nonoral, and specific ROAs for ER oxycodone and comparators (ER morphine and ER oxymorphone) before and after ORF introduction. Significant reductions occurred for 8 outcome measures of ORF versus OC historically. Abuse of ORF was 41% lower (95% CI: -44 to -37) than historical abuse for OC, with oral abuse 17% lower (95% CI: -23 to -10) and nonoral abuse 66% lower (95% CI: -69 to -63). Significant reductions were not observed for comparators. Observations were consistent with the goals of a tamper resistant formulation for an opioid. Further research is needed to determine the persistence and generalizability of these findings.

PERSPECTIVE

This article presents preliminary findings indicating that 8 outcome measures of abuse of a reformulated ER oxycodone were lower than that for original ER oxycodone historically, particularly through nonoral ROAs that require tampering (ie, injection, snorting, smoking), in a sentinel sample of individuals assessed for substance use problems for treatment planning.

The paradoxical effects of using antiretroviral-based microbicides to control HIV epidemics

Vaginal microbicides, designed to prevent HIV infection in women, are one of the most promising biomedical interventions. Clinical trials of second-generation microbicides have begun; if shown to be effective, they could be licensed within 5-10 years. Because these microbicides contain antiretrovirals (ARVs), they could be highly effective. However, there is concern that, if used by HIV-positive women, ARV resistance may evolve. By analyzing a mathematical model, we find that adherence could have both beneficial and detrimental effects on trial outcomes. Most importantly, we show that planned trial designs could mask resistance risks and therefore enable high-risk microbicides to pass clinical testing. We then parameterize a transmission model using epidemiological, clinical, and behavioral data to predict the consequences of wide-scale usage of high-risk microbicides in a heterosexual population. Surprisingly, we show that reducing a participant's risk of resistance during a trial could lead to unexpectedly high rates of resistance afterward when microbicides are used in public health interventions. We also find that, paradoxically, although microbicides will be used by women to protect themselves against infection, they could provide greater benefit to men. More infections in men than in women will be prevented if there is a high probability that ARVs are systemically absorbed, microbicides are less than approximately 50% effective, and/or adherence is less than approximately 60%. Men will always benefit more than women in terms of infections prevented per resistant case; but this advantage decreases as the relative fitness of drug-resistant strains increases. Interventions that use ARV-based microbicides could have surprising consequences.

The impact of acute herpes zoster pain and discomfort on functional status and quality of life in older adults

OBJECTIVES

To describe the interference of herpes zoster (HZ) pain and discomfort with activities of daily living (ADLs) and health-related quality of life (HRQL) during the acute rash phase, and to quantify the relationship between acute HZ pain and discomfort and impaired ADLs and HRQL in older persons.

METHODS

Prospective, observational study of 160 HZ outpatients age > or =60 at 4 US study sites who completed the Zoster Brief Pain Inventory (ZBPI), Zoster Impact Questionnaire (ZIQ), McGill Pain Questionnaire, EuroQol, and SF-12 questionnaires on a predetermined schedule. Patients rated interference on a 0 to 10 scale for ADL items in the ZBPI and the ZIQ. Interference scores were averaged to create summary measures for the ZBPI items (ZBPI ADLI) and ZIQ items (ZIQ ADLI). A composite pain score was used in mixed-effects models analyses of the association between pain and discomfort and ADLI and HRQL measures during the first 35 days after HZ rash onset.

RESULTS

HZ pain interfered with all ADLs but interference was greatest for enjoyment of life, sleep, general activity, leisure activities, getting out of the house, and shopping. For every 1.0 point increase in pain and discomfort intensity, there was a 0.69 and 0.53 point increase in ZBPI and ZIQ interference, respectively, and a 2.81 point, 1.57 point, and 1.95 point decrease in EuroQol, SF-12 physical, and SF-12 mental scales, respectively.

DISCUSSION

Acute zoster pain and discomfort has a significant negative impact on functional status and HRQL in older adults. The magnitude of interference increases with increasing pain and discomfort intensity.

Decreased choline and creatine concentrations in centrum semiovale in patients with generalized anxiety disorder: relationship to IQ and early trauma

We have demonstrated, using proton magnetic resonance spectroscopy imaging ((1)H-MRSI), elevations of N-acetyl-aspartate/creatine (NAA/CR) in right dorsolateral prefrontal cortex (DLPFC) in patients with generalized anxiety disorder (GAD) in comparison to healthy volunteers. A recent study indicates that the volume of prefrontal cortical white matter may be disproportionately increased in man in comparison to other primate species, with evolutionary implications. We therefore re-analyzed the identical scans with a specific focus on the centrum semiovale (CSO) as a representative region of interest of cerebral white matter. The central hypothesis was, in accordance with our gray matter findings, that patients with GAD, in comparison to healthy controls, would exhibit either an increase in NAA in CSO, or alternatively demonstrate reductions in concentrations of choline (CHO)-containing compounds and/or creatine+phosphocreatine (CR). MRSI scans that were obtained from an earlier [Mathew, S.J., Mao, X., Coplan, J.D., Smith, E.L., Sackeim, H.A., Gorman, J.M., Shungu, D.C., 2004. Dorsolateral prefrontal cortical pathology in generalized anxiety disorder: a proton magnetic resonance spectroscopic imaging study. American Journal of Psychiatry 161, 1119-1121] sample of 15 patients with GAD [6 with early trauma (ET)] and 15 healthy age- and sex-matched volunteers were analyzed further for CSO metabolite alterations. Self-reported worry was scored using the Penn State Worry Questionnaire (PSWQ) and intelligence was assessed using the Wechsler Abbreviated Scale of Intelligence (WASI). Serial multislice/multivoxel MRSI scans had been performed on a 1.5-T MRI. Using absolute quantification methods for metabolite concentrations, we examined NAA, CHO and CR. GAD patients without ET exhibited bilaterally decreased concentrations of CHO and CR in CSO in comparison to healthy volunteers, whereas GAD patients with ET were indistinguishable from controls. In patients with GAD, high IQ was paired with greater worry, whereas in healthy volunteers, high IQ was associated with less worry. In all subjects, IQ inversely predicted left and right CSO CHO concentrations, independent of age, sex, group assignment and PSWQ scores. The CSO may therefore represent a neural substrate that exhibits reductions in CHO and CR metabolite concentrations that are inversely associated with GAD symptomatology and, in the case of CHO, with intelligence. These conclusions are deemed preliminary due to small sample size, with further study of cerebral WM in anxiety disorders suggested.

Cross-Clade Reactivity of HIV-1-Specific T-cell Responses in HIV-1-Infected Individuals From Botswana and Cameroon

An effective HIV type 1 (HIV-1) vaccine will likely require elicitation of broadly reactive cell-mediated immune (CMI) responses against divergent HIV-1 clades. We compared anti-HIV-1 T-cell immune responses among 363 unvaccinated adults infected with diverse HIV-1 clades. Response rates to clade B Gag and/or clade B Nef in Botswana (95%) and Cameroon (98%) were similar when compared with those in countries previously studied, including Brazil (92%), Thailand (96%), South Africa (96%), Malawi (100%), and the United States (100%). Substantial cross-clade cell-mediated immune responses in Botswana and Cameroon confirm previous findings in a larger, more genetically diverse collection of HIV-1 samples.

Synchronized maternal-infant elevations of primate CSF CRF concentrations in response to variable foraging demand

BACKGROUND

The study of environment-gene interactions during neurodevelopment may facilitate our understanding of the origins of psychiatric disorders. Environmental contribution to the neurobiology of psychopathology is perhaps most relevant during infancy, where vulnerability to early-life stressors is particularly evident.

OBJECTIVES

In the current study, we wished to examine if central corticotropin-releasing factor (CRF) would provide a plausible biological vehicle for synchronized increases in mothers and their infant.

METHODS

Twenty-four mother-infant bonnet macaques (Macaca radiata) dyads, of known age and weight served as subjects. The subjects were group-housed in four pens of 5-7 dyads each, stabilized for several weeks prior to the study period. Although adequate food was always available, mothers faced uncertainty of food availability for 16 weeks within the first year of infant life, through a procedure dubbed "variable foraging demand" (VFD). Pre- and post-VFD cerebrospinal fluid (CSF) samples were obtained simultaneously on mothers and infants.

RESULTS

Maternal CSF CRF concentrations exhibited a significant mean elevation of 26% from pre-VFD to post-VFD; there was no effect of number of days postpartum on maternal pre-VFD CSF CRF levels. There was a significant mean increase (45%) in infant CSF CRF concentrations over the 16-week period of the VFD paradigm. No infant sex differences were evident. Post-VFD minus pre-VFD differences in infant CSF CRF concentrations were positively correlated (r = .52; N = 16; P = .0384) with the magnitude of maternal CRF response to VFD, providing evidence of synchronized CSF CRF expression by the dyad.

CONCLUSION

This parallel response within the dyad suggests, as one testable hypothesis, that maternal responsivity to the stress of the VFD condition is "communicated" between mother and infant via a CRF-mediated mechanism. The VFD stressor produces a parallel activation of the central CRF system in both mothers and their infants.

Cross‐Reactivity of Anti–HIV‐1 T Cell Immune Responses among the Major HIV‐1 Clades in HIV‐1–Positive Individuals from 4 Continents

BACKGROUND

The genetic diversity of human immunodeficiency virus type 1 (HIV-1) raises the question of whether vaccines that include a component to elicit antiviral T cell immunity based on a single viral genetic clade could provide cellular immune protection against divergent HIV-1 clades. Therefore, we quantified the cross-clade reactivity, among unvaccinated individuals, of anti-HIV-1 T cell responses to the infecting HIV-1 clade relative to other major circulating clades.

METHODS

Cellular immune responses to HIV-1 clades A, B, and C were compared by standardized interferon- gamma enzyme-linked immunospot assays among 250 unvaccinated individuals, infected with diverse HIV-1 clades, from Brazil, Malawi, South Africa, Thailand, and the United States. Cross-clade reactivity was evaluated by use of the ratio of responses to heterologous versus homologous (infecting) clades of HIV-1.

RESULTS

Cellular immune responses were predominantly focused on viral Gag and Nef proteins. Cross-clade reactivity of cellular immune responses to HIV-1 clade A, B, and C proteins was substantial for Nef proteins (ratio, 0.97 [95% confidence interval, 0.89-1.05]) and lower for Gag proteins (ratio, 0.67 [95% confidence interval, 0.62-0.73]). The difference in cross-clade reactivity to Nef and Gag proteins was significant (P<.0001).

CONCLUSIONS

Cross-clade reactivity of cellular immune responses can be substantial but varies by viral protein.

Development of a measure of the burden of pain due to herpes zoster and postherpetic neuralgia for prevention trials: adaptation of the brief pain inventory

In preparation for clinical trials of a vaccine against herpes zoster (HZ), we conducted a prospective, observational study to evaluate (1) the Zoster Brief Pain Inventory (ZBPI), an HZ-specific questionnaire to quantify HZ pain and discomfort, (2) an operational definition of postherpetic neuralgia (PHN), and (3) a severity-duration measure of the burden of illness caused by HZ. HZ patients aged 60 years or older (n = 121) were enrolled within 14 days of rash onset and completed ZBPI, McGill Pain Questionnaire Present Pain Intensity (PPI), quality of life (QoL), and activities of daily living (ADL) questionnaires on a predetermined schedule. Reliability, measured by intraclass correlation coefficients within 14 days of rash onset, ranged between 0.63 and 0.78. ZBPI pain scores were strongly correlated with other pain measures, interference with ADL, and worsening QoL. The operational definition of PHN, a ZBPI pain score of 3 or greater occurring 90 or more days after rash onset, had high agreement with pain worse than mild on the PPI (kappa = 0.72). The ZBPI pain severity-duration measure had high correlations with severity-duration measures of ADL interference, worsening QoL, and other pain scales. These findings support the validity and utility of the ZBPI, the definition of PHN, and the severity-duration measure of the burden of HZ illness.

PERSPECTIVE

Herpes zoster pain, as measured by the ZBPI severity-duration measure, is associated with impairment in daily living activities and quality of life. The ZBPI measure appears useful for quantifying herpes zoster pain, postherpetic neuralgia, and impairment in daily living activities for clinical trials of herpes zoster prevention.

Impact of indinavir on the quality of life in patients with advanced HIV infection treated with zidovudine and lamivudine

OBJECTIVE

In AIDS Clinical Trial Group (ACTG) study 320, triple-combination antiretroviral therapy including indinavir significantly slowed progression to acquired immunodeficiency syndrome or death, compared with treatment with dual nucleoside reverse-transcriptase inhibitors (NRTIs) alone, in zidovudine-experienced patients with advanced human immunodeficiency virus (HIV) infection. We examined the impact of indinavir on quality of life in participants from this study.

METHODS

A total of 1156 protease inhibitor- and lamivudine-naive patients stratified by CD4 cell count (<or=50 and 51-200 cells/mm(3)) were randomized to receive zidovudine (or stavudine) and lamivudine, with or without indinavir. Health-related quality of life was measured using the ACTG QoL601-602 questionnaire, which assesses general health status measured on a visual analogue scale and 8 specific health-related domains. Quality-adjusted survival time was estimated using the visual analogue scale for general health.

RESULTS

Mean changes in general health scores after 24 weeks were +2.9 in the triple-therapy group versus -0.2 in the dual-therapy group (P=.018). By week 24, scores in all specific domains were higher with triple-drug therapy than dual-drug therapy, with statistically significant differences in role function, energy, and pain scores. Benefits of triple-drug therapy were largely confined to patients with CD4 cell counts of <or=50 cells/mm(3). Quality-adjusted survival time did not differ significantly between the 2 treatment groups.

CONCLUSIONS

Triple-drug therapy with indinavir and 2 NRTIs resulted in a significant improvement in general health status after 24 weeks, especially in patients with low CD4 cell counts. Patients receiving triple-drug therapy also had significantly better role function, energy, and pain scores than did patients treated with dual-drug therapy.

Indinavir did not further increase mean triglyceride levels in HIV-infected patients treated with nucleoside reverse transcriptase inhibitors: an analysis of three randomized clinical trials

OBJECTIVES

Metabolic abnormalities including hyperlipidemia have developed in patients infected with the human immunodeficiency virus (HIV) after treatment with protease inhibitor drugs. It is unclear whether the deleterious effects on plasma triglyceride concentrations observed in patients receiving highly active antiretroviral therapy are a class effect of protease inhibitors. Hypertriglyceridemia may constitute a risk factor for cardiovascular disease. The purpose of this retrospective analysis of HIV-infected patients enrolled in three randomized, double-blind trials of indinavir therapy was to determine whether indinavir use was associated with a larger increase in triglyceride levels than treatment without a protease inhibitor.

METHODS

Using a mixed-effects model, we compared average changes in nonfasting plasma triglyceride levels among randomized treatment groups for each protocol separately.

RESULTS

The median increase in triglyceride levels during the 1st year of antiretroviral monotherapy was less with indinavir than with either zidovudine or stavudine. The combination of indinavir and nucleoside-analogue reverse-transcriptase inhibitors (NRTI) resulted in smaller increments in triglyceride levels than NRTI monotherapy. Indinavir also augmented the reduction in triglyceride levels observed with combination therapy using zidovudine and lamivudine in persons with far advanced HIV-infection. However, up to 7% of patients receiving a NRTI and indinavir experienced elevations of nonfasting triglyceride levels in excess of 750 mg/dl.

CONCLUSIONS

On average, the combination of indinavir and NRTI therapy was not associated with a greater elevation of non-fasting triglyceride levels in HIV-infected men with at least moderately advanced immunosuppression than treatment with NRTI drugs alone.

Incidence of myocardial infarction in randomized clinical trials of protease inhibitor-based antiretroviral therapy: an analysis of four different protease inhibitors

Protease inhibitor (PI) therapy for patients infected with the human immunodeficiency virus has been associated with lipid disorders and insulin resistance. We compared the incidence of myocardial infarction (MI) among participants receiving treatment with PIs with or without nucleoside reverse transcriptase inhibitors (nRTIs) to nRTI therapy alone in 30 phase II/III double-blind, randomized studies conducted before 1999 for the first 4 PI drugs. In most trials included in this analysis, participants could receive combination therapy with a PI plus nRTIs in open-label extensions after the blinded phase concluded. Person-years (PY) of follow-up were calculated from treatment initiation to the diagnosis of MI, or to the end of the randomized phases for nRTI-only therapy or to the conclusion of the studies for PI-containing regimens. Separate analyses were conducted for the randomized and the randomized-plus-extension phases. Among 10,986 participants, 7951 (72%) received PI drugs at some point for an average duration of 12 months. There were 10 MIs (1.31/1000 PY) in the randomized phases and 19 MIs (1.63/1000 PY) in the randomized-plus-extension phases. The overall stratified relative risk of MI for PI-containing (1.82 MI/1000 PY) versus nRTI-only (1.05 MI/1000 PY) regimens of 1.69 was not significantly increased (95% confidence interval [CI], 0.54 to 7.48). The absolute difference in MI risk was +0.77 (95% CI, -0.71 to +2.26) MIs/1000 PY. Compared with NRTI-only therapy, patients receiving PI-containing regimens for an average of 1 year did not have significantly more MIs, but the upper bound of the 95% CI indicates there may be up to 2.3 additional MIs per 1000 PY. Although studies with a longer duration of PI therapy are in progress to assess whether a later increase in MI incidence occurs, our analysis did not demonstrate a dramatic increase in MI risk during the first year of PI therapy.

Poor sensitivity of polymerase chain reaction assays of genital skin swabs and urine to detect HPV 6 and 11 DNA in men

BACKGROUND

A possible reason for the failure to detect human papillomavirus (HPV) DNA in asymptomatic men who are likely to be infected is the sensitivity of the detection methods.

GOAL

The goal of this study was to identify a method for sampling the anogenital skin of men that was simple and well tolerated and that would permit the detection of asymptomatic or subclinical HPV infection, which is thought to occur commonly in sexually active men.

STUDY DESIGN

Swabs of genital skin and urine from men at high and low risk of infection with types 6 and 11 were tested for HPV by polymerase chain reaction.

RESULTS

These specimens had a low sensitivity for HPV detection, often because inadequate material was collected on the swab.

CONCLUSION

Noninvasive sampling of genital skin to identify individuals with subclinical HPV infection remains a challenge. Future studies should involve the use of more abrasive sampling devices (such as cytobrushes), perhaps combined with some type of soap to dislodge more epithelial cells.