Factors associated with participation and completion of a survey-based study.

PURPOSE: The Healthy Work Place (HWP) study investigated methods to improve clinicians' dissatisfaction and burnout. The purpose of this paper is to identify factors that influenced study enrollment and completion and assess effects of initial clinic site enrollment rates on clinician outcomes, including satisfaction, burnout, stress and intent to leave practice. DESIGN/METHODOLOGY/APPROACH: In total, 144 primary care clinicians (general internists, family physicians, nurse practitioners and physician assistants) at 14 primary care clinics were analyzed. FINDINGS: In total, 72 clinicians enrolled in the study and completed the first survey (50 percent enrollment rate). Of these, 10 did not complete the second survey (86 percent completion rate). Gender, type, burnout, stress and intervention did not significantly affect survey completion. Hence, widespread agreement about most moral/ethical issues (72 percent vs 22 percent; p=0.0060) and general agreement on treatment methods (81 percent vs 50 percent; p=0.0490) were reported by providers that completed both surveys as opposed to just the initial survey. Providers with high initial clinic site enrollment rates (=50 percent providers) obtained better outcomes, including improvements in or no worsening of satisfaction (odds ratio (OR)=19.16; p=0.0217) and burnout (OR=6.24; p=0.0418). SOCIAL IMPLICATIONS: More providers experiencing workplace agreement completed the initial and final surveys, and providers at sites with higher initial enrollment rates obtained better outcomes including a higher rate of improvement or no worsening of job satisfaction and burnout. ORIGINALITY/VALUE: There is limited research on clinicians' workplace and other factors that influence their participation in survey-based studies. The findings help us to understand how these factors may affect quality of data collecting and outcome. Thus, the study provides us insight for improvement of quality in primary care.

Validity of Using Inpatient and Outpatient Administrative Codes to Identify Acute Venous Thromboembolism: The CVRN VTE Study.

BACKGROUND: Administrative data are frequently used to identify venous thromboembolism (VTE) for research and quality reporting. However, the validity of these codes, particularly in outpatients, has not been well-established. OBJECTIVE: To determine how well International Classification of Diseases, Ninth Revision (ICD-9) codes for VTE predict chart-confirmed acute VTE in inpatient and outpatients. PATIENTS AND METHODS: We selected 4642 adults with an incident ICD-9 diagnosis of VTE between years 2004 and 2010 from the Cardiovascular Research Network Venous Thromboembolism cohort study. Medical charts were reviewed to determine validity of events. Positive predictive values (PPVs) of ICD-9 codes were calculated as the number of chart-validated VTE events divided by the number with specific VTE codes. Analyses were stratified by VTE type [pulmonary embolism (PE), deep venous thrombosis (DVT)], code position (primary, secondary), and setting [hospital/emergency department (ED), outpatient]. RESULTS: The PPV for any diagnosis of VTE was 64.6% for hospital/ED patients and 30.9% for outpatients. Primary diagnosis codes from hospital/ED patients were more likely to represent acute VTE than secondary diagnosis codes (78.9% vs. 44.4%, P<0.001). Primary hospital/ED codes for PE and lower extremity DVT had higher PPV than for upper extremity DVT (89.1%, 74.9%, and 58.1%, respectively). Outpatient codes were poorly predictive of acute VTE: 28.0% for PE and 53.6% for lower extremity DVT. CONCLUSIONS: ICD-9 codes for VTE obtained from outpatient encounters or from secondary diagnosis codes do not reliably reflect acute VTE. More accurate ways of identifying VTE in outpatients are needed before these codes can be adopted for research or policy purposes.

Thromboembolic complications following a first isolated episode of superficial vein thrombosis: a cross-sectional retrospective study.

Superficial vein thrombosis (SVT) may be associated with complications such as venous thromboembolism (VTE) and recurrent SVT. The purpose of this study was to explore risk factors among patients with a first isolated episode of SVT (index SVT) involving upper and lower extremities and to estimate the prevalence of VTE complications within 1 year of index SVT. Retrospective chart review of electronic records at Marshfield Clinic in Wisconsin identified 381 subjects with a first isolated SVT diagnosis (male/female: 170/211; median age 59.4 years). Patients were stratified based on whether they did (n = 44; 11.5 %) or did not (n = 337; 88.5 %) experience VTE complications and whether they did (n = 25; 6.6 %) or did not (n = 356; 93.4 %) experience pulmonary embolism (PE) and/or deep vein thrombosis (DVT) within 1 year of index SVT. There were 49 complications among 44 patients; these included DVT (n = 18, 36.7 %), propagation of SVT (n = 18, 36.7 %), PE (n = 9, 18.4 %), new SVT at different location (n = 3, 6.1 %), and recurrent SVT (n = 1, 2.0 %). Univariate analysis of all VTE complications identified seven potential risk factors and similar analysis of PE/DVT complications identified eight potential risk factors, with six common risk factors identified in both analyses. Multivariate analysis identified indwelling venous catheter 30 days prior to SVT (p = 0.044), cancer history with treatment in the previous year (p = 0.001), and non-surgical trauma 7 days prior to SVT (p < 0.001) as independent risk factors for PE/DVT complications. Independent risk factors identified in the current study may convey greater risk for VTE complications, especially PE/DVT, following an initial isolated SVT episode.

Reinitiating warfarin: relationships between dose and selected patient, clinical and hospital measures.

BACKGROUND: Warfarin is an oral anticoagulant used in the long-term treatment/prevention of venothromboembolic disease. Patients undergoing elective surgical and non-surgical procedures may require temporary warfarin discontinuation followed by reinitiation after their procedure. Because little information is available regarding best methods for warfarin reinitiation, we investigated current practices to inform management decisions. METHODS: Subjects were required to have a known and stable warfarin dose prior to discontinuation, which was operationalized by requiring, within 7-days prior to discontinuation, that they have at least one INR in therapeutic range (2.0-3.5), no INR(s) out of range, and no more than a 15% change in warfarin dose. Stable dose prior to discontinuation was defined as the average daily dose received in the 7 days immediately prior to discontinuation. Reinitiation dose was defined as the average daily dose received in the first 3 days after warfarin was restarted. Subjects were divided into three groups based on whether they received approximately the same, a higher, or a lower dose at reinitiation and were also grouped by calendar time into three distinct periods that reflected differing levels of availability of electronic and patient care data that may impact reinitiation dose decisions. These groupings facilitated analyses and descriptions of trends in reinitiation dosing and supported other analyses, including tests for association between dose group and selected subject demographic, clinical, medication and hospitalization measures. All study data were abstracted from Marshfield Clinic electronic patient care and administrative databases and electronic patient care databases from Ministry St. Joseph's Hospital (Marshfield, WI). RESULTS: We identified 205 subjects with warfarin temporarily discontinued between 1994 and 2012: 99 subjects in same dose group, 32 subjects in the low group, and 74 subjects in the high group. Because relatively wide differences were observed in the proportion of same dose subjects during more recent years (2007-2012) compared to earlier years (54% vs 35%), we focused our analyses on this recent period, which included 140 subjects. Review of physician notes and other documents yielded virtually no information about reasons for reinitiation dose decisions. In addition, tests for association between reinitiation dose group and subject demographic, clinical, medication and hospital measures were uniformly uninformative. CONCLUSIONS: We observed varied dosing strategies for reinitiating patients on warfarin and, in more recent years, an apparent trend toward reinitiating patients on the same dose. However we could not associate dosing strategy with specific patient demographic, clinical, medication or hospital factors. Many factors influence whether a physician reinitiates a patient at a different dose than his/her prior stable warfarin dose. However, in the absence of clinical indications for modification, we believe patients with a previously established effective dose should be reinitiated at that same dose following temporary warfarin discontinuation.

Factors that affect rate of INR decline after warfarin discontinuation.

BACKGROUND: Despite vast literature on warfarin, optimal strategies for temporarily discontinuing and restarting warfarin have not been established. To improve warfarin discontinuation processes, we investigated known medical and genetic factors that influence stable warfarin dose to determine how well they predict the time until patients become subtherapeutic after discontinuing warfarin. METHODS: This was a retrospective cohort study of patients who temporarily discontinued warfarin before an elective procedure andhad at least 2 international normalized ratio (INR) values available during the discontinuation period. Data abstracted included date of discontinuation, warfarin dose, INR values, body surface area, gender, age, indication for warfarin, current medications, eGFR, and presence of bridging therapy with heparin. DNA variants were tested in CYP2C9, VKORC1, and CYP4F2 genes. Subjects were excluded if they received vitamin K, fresh frozen plasma, or prothrombin complexes to reverse anticoagulation. Asymptotic regression models were used to approximate decline in INR during warfarin clearance. Spearman correlations and Kruskal-Wallis tests were used to characterize associations of model estimates with quantitative variables and for group comparisons, respectively. RESULTS: Other than the expected association with baseline INR, correlations of model parameter estimates with clinical variables were generally weak and not statistically significant. The strongest associations with slope were with serum creatinine and eGFR. There were no significant associations with CYP2C9, VKORC1, or CYP4F2 DNA variants, but there were few subjects combined in the nonwild groups for CYP2C9. Estimated slope showed moderate correlation with observed dose. CONCLUSION: Known clinical and genetic predictors of therapeutic dose were not found to be strongly associated with the slope of INR decline after warfarin discontinuation.

A randomized controlled trial of genotype-based Coumadin initiation.

PURPOSE: A randomized controlled trial was conducted in patients initiating warfarin to determine whether algorithms that incorporate genotypes affecting warfarin metabolism and function, and Vitamin K metabolism improve prediction of therapeutic warfarin dose and anticoagulation management. METHODS: A total of 230 patients were randomized to either a clinical arm where dosing algorithms considered only clinical information or an interventional arm where dosing algorithms used clinical and genotypic variables (CYP2C9, CYP4F2, and VKORC1). Subjects in the interventional arm were genotyped within 5 hours, and the initial dose was informed by genotype. Primary endpoints were absolute prediction error relative to therapeutic dose, and time in therapeutic target range during the first 14 days. Secondary endpoints included time to stable dose in therapeutic range, time to first international normalization ratio >4, and warfarin-related adverse events. RESULTS: The model including genetics more accurately identified therapeutic dose twice as often as the clinical model (65.3% vs. 34.7%) (P < 0.0001). Patients in the interventional arm did not achieve greater time in therapeutic range. Study arms were similar regarding time to international normalization ratio >4 and adverse events. CONCLUSION: Genotype-informed dosing clearly improved prediction of therapeutic dose beyond that available with clinical parameters. Genetic information did not affect time in therapeutic target range during the first 14 days of therapy. Current management practices with the vagaries in dose adjustment after warfarin initiation exert a strong influence on traditional clinical outcomes.

Absence of novel CYP4F2 and VKORC1 coding region DNA variants in patients requiring high warfarin doses.

OBJECTIVE: Warfarin is an FDA-approved oral anticoagulant for long-term prevention of thromboembolism. Substantial inter-individual variation in dosing requirements and the narrow therapeutic index of this widely-prescribed drug make safe initiation and dose stabilization challenging. Single nucleotide polymorphisms (SNPs) occurring in CYP2C9, VKORC1, and CYP4F2 genes are known to impact dose, and VKORC1 and CYP4F2 polymorphisms are associated with higher therapeutic dose requirements in our cohort. However, the most advanced regression models using personal, clinical, and genetic factors to predict individual stable dose account for only 50% to 60% of the observed variability in stable therapeutic dose in Caucasians. DESIGN AND METHODS: In this study, we used DNA sequence analysis to determine whether additional variants in CYP4F2 and VKORC1 gene coding regions contribute to variable dosing requirements among individuals for whom the actual dose was the highest relative to regression model- predicted dose. RESULTS AND CONCLUSIONS: No novel DNA variants in the coding regions of these genes were identified among subjects requiring high warfarin doses, suggesting that other factors yet to be defined contribute to variability in warfarin dose requirements in this subset of our cohort.

The impact of serum glucose on clinical outcomes in patients hospitalized with community-acquired pneumonia.

PURPOSE: Community-acquired pneumonia (CAP) is a common medical condition resulting in excess morbidity, mortality, and high rates of hospitalization. Despite high hospitalization rates for CAP, the relationship between abnormal glucose levels (hyperglycemia and hypoglycemia) and the seriousness of the illness as measured by length of stay (LOS) is not well established. We examined relationships of CAP to multiple factors that impact predictability and severity of the disease process. They include glycemic control; hospital utilization, including LOS; 30-day hospital readmission; intensive care unit (ICU) admissions, adjusting for comorbidities; illness severity; and timing of antibiotic treatment. METHODS: We conducted a retrospective observational cohort study of adult patients hospitalized for CAP between January 1, 1992 and June 23, 2007. Case screening was conducted electronically using International Classification of Diseases, 9th Revision (ICD-9) codes 480.0-487.9. Subsequent medical record abstraction yielded 969 qualifying cases with comprehensive data on past and current medical problems. RESULTS: Serum glucose levels at admission were independently associated with LOS for CAP patients. Patients with levels between 90 mg/dL and 140 mg/dL on admission had shorter LOS compared to those with levels of < 90 mg/dL and > 140 mg/dL (median 3.9 vs 4.2 days, P = .04). Multivariate analyses confirmed the univariate results. Serum glucose levels at initial hospitalization were not associated with 30-day hospital readmission (P =.34) or ICU admission (P = .48). CONCLUSIONS: Abnormal glucose levels are an independent predictor of increased LOS for CAP. Control of blood glucose may lead to improved outcomes, including shortened LOS, and should be a priority in CAP management.

Administrative codes inaccurately identify recurrent venous thromboembolism: The CVRN VTE study.

BACKGROUND: Studies using administrative data commonly rely on diagnosis codes to identify venous thromboembolism (VTE) events. Our objective was to assess the validity of using International Classification of Disease, 9th Revision (ICD-9) codes in identifying recurrent VTE. MATERIALS AND METHODS: Among 5497 adults with confirmed incident VTE from four healthcare delivery systems in the Cardiovascular Research Network (CVRN), we identified all subsequent inpatient, emergency department (ED), and ambulatory clinical encounters associated with an ICD-9 code for VTE (combined with relevant radiology procedure codes for inpatient/ED VTE codes in the secondary discharge position or outpatient codes) during the follow-up period. Medical records were reviewed using standardized diagnostic criteria to assess for the presence of new, recurrent VTE. The positive predictive value (PPV) of codes was calculated as the number of valid events divided by total encounters. RESULTS: We identified 2397 encounters that were considered potential recurrent VTE by ICD-9 codes. However, only 31.1% (95%CI: 29.3-33.0%) of encounters were verified by reviewers as true recurrent VTE. Hospital or ED encounters with VTE codes in the primary position were more likely to represent valid recurrent VTE (PPV 61.3%, 95%CI: 56.7-66.3%) than codes in secondary positions (PPV 35.4%, 95%CI: 31.9-39.3%), or outpatient codes (PPV 20.3%, 95%CI: 18.3-22.5%). PPV was low for all VTE types (29.9% for pulmonary embolism, 38.3% for lower and 37.7% for upper extremity deep venous thrombosis, and 14.1% for other VTE). CONCLUSIONS: ICD-9 codes do not accurately identify new VTE events in patients with a prior history of VTE.

Treatment and Outcomes of Acute Pulmonary Embolism and Deep Venous Thrombosis: The CVRN VTE Study.

BACKGROUND: Few studies describe both inpatient and outpatient treatment and outcomes of patients with acute venous thromboembolism in the United States. METHODS: A multi-institutional cohort of patients diagnosed with confirmed pulmonary embolism or deep venous thrombosis during the years 2004 through 2010 was established from 4 large, US-based integrated health care delivery systems. Computerized databases were accessed and medical records reviewed to collect information on patient demographics, clinical risk factors, initial antithrombotic treatment, and vital status. Multivariable Cox regression models were used to estimate the risk of death at 90 days. RESULTS: The cohort comprised 5497 adults with acute venous thromboembolism. Pulmonary embolism was predominantly managed in the hospital setting (95.0%), while 54.5% of patients with lower extremity thrombosis were treated as outpatients. Anticoagulant treatment differed according to thromboembolism type: 2688 patients (92.8%) with pulmonary embolism and 1625 patients (86.9%) with lower extremity thrombosis were discharged on anticoagulants, compared with 286 patients (80.1%) with upper extremity thrombosis and 69 (54.8%) patients with other thrombosis. While 4.5% of patients died during the index episode, 15.4% died within 90 days. Pulmonary embolism was associated with a higher 90-day death risk than lower extremity thrombosis (adjusted hazard ratio 1.23; 95% confidence interval, 1.04-1.47), as was not being discharged on anticoagulants (adjusted hazard ratio 5.56; 95% confidence interval, 4.76-6.67). CONCLUSIONS: In this multicenter, community-based study of patients with acute venous thromboembolism, anticoagulant treatment and outcomes varied by thromboembolism type. Although case fatality during the acute episode was relatively low, 15.4% of people with thromboembolism died within 90 days of the index diagnosis.

Anxiety, Depression, and Adverse Clinical Outcomes in Patients With Atrial Fibrillation Starting Warfarin: Cardiovascular Research Network WAVE Study.

BACKGROUND: Anxiety and depression are associated with worse outcomes in several cardiovascular conditions, but it is unclear whether they affect outcomes in atrial fibrillation (AF). In a large diverse population of adults with AF, we evaluated the association of diagnosed anxiety and/or depression with stroke and bleeding outcomes. METHODS AND RESULTS: The Cardiovascular Research Network WAVE (Community-Based Control and Persistence of Warfarin Therapy and Associated Rates and Predictors of Adverse Clinical Events in Atrial Fibrillation and Venous Thromboembolism) Study included adults with AF newly starting warfarin between 2004 and 2007 within 5 health delivery systems in the United States. Diagnosed anxiety and depression and other patient characteristics were identified from electronic health records. We identified stroke and bleeding outcomes from hospitalization databases using validated International Classification of Diseases, Ninth Revision (ICD-9), codes. We used multivariable Cox regression to assess the relation between anxiety and/or depression with outcomes after adjustment for stroke and bleeding risk factors. In 25 570 adults with AF initiating warfarin, 490 had an ischemic stroke or intracranial hemorrhage (1.52 events per 100 person-years). In multivariable analyses, diagnosed anxiety was associated with a higher adjusted rate of combined ischemic stroke and intracranial hemorrhage (hazard ratio, 1.52; 95% confidence interval, 1.01-2.28). Results were not materially changed after additional adjustment for patient-level percentage of time in therapeutic anticoagulation range on warfarin (hazard ratio, 1.56; 95% confidence interval, 1.03-2.36). In contrast, neither isolated depression nor combined depression and anxiety were significantly associated with outcomes. CONCLUSIONS: Diagnosed anxiety was independently associated with increased risk of combined ischemic stroke and intracranial hemorrhage in adults with AF initiating warfarin that was not explained by differences in risk factors or achieved anticoagulation quality.

CYP4F2 genetic variant alters required warfarin dose.

Warfarin is an effective, commonly prescribed anticoagulant used to treat and prevent thrombotic events. Because of historically high rates of drug-associated adverse events, warfarin remains underprescribed. Further, interindividual variability in therapeutic dose mandates frequent monitoring until target anticoagulation is achieved. Genetic polymorphisms involved in warfarin metabolism and sensitivity have been implicated in variability of dose. Here, we describe a novel variant that influences warfarin requirements. To identify additional genetic variants that contribute to warfarin requirements, screening of DNA variants in additional genes that code for drug-metabolizing enzymes and drug transport proteins was undertaken using the Affymetrix drug-metabolizing enzymes and transporters panel. A DNA variant (rs2108622; V433M) in cytochrome P450 4F2 (CYP4F2) was associated with warfarin dose in 3 independent white cohorts of patients stabilized on warfarin representing diverse geographic regions in the United States and accounted for a difference in warfarin dose of approximately 1 mg/day between CC and TT subjects. Genetic variation of CYP4F2 was associated with a clinically relevant effect on warfarin requirement.

Evaluation of genetic factors for warfarin dose prediction.

OBJECTIVES: Warfarin is a commonly prescribed anticoagulant drug used to prevent thromboses that may arise as a consequence of orthopedic and vascular surgery or underlying cardiovascular disease. Warfarin is associated with a notoriously narrow therapeutic window where small variations in dosing may result in hemorrhagic or thrombotic complications. To ultimately improve dosing of warfarin, we evaluated models for stable maintenance dose that incorporated both clinical and genetic factors. METHOD: A model was constructed by evaluating the contribution to dosing variability of the following clinical factors: age, gender, body surface area, and presence or absence of prosthetic heart valves or diabetes. The model was then sequentially expanded by incorporating polymorphisms of cytochrome P450 (CYP) 2C9; vitamin K 2,3 epoxide reductase complex, subunit 1 (VKORC1); gamma carboxylase; factor VII; and apolipoprotein (Apo) E genes. RESULTS: Of genetic factors evaluated in the model, CYP2C9 and VKORC1 each contributed substantially to dose variability, and together with clinical factors explained 56% of the individual variability in stable warfarin dose. In contrast, gamma carboxylase, factor VII and Apo E polymorphisms contributed little to dose variability. CONCLUSION: The importance of CYP2C9 and VKORC1 to patient-specific dose of warfarin has been confirmed, while polymorphisms of gamma carboxylase, factor VII and Apo E genes did not substantially contribute to predictive models for stable warfarin dose.