Publications
Department of Medicine faculty members published more than 3,000 peer-reviewed articles in 2022.
2017
BACKGROUND
The use of non-vitamin K oral anticoagulants (NOACs) has increased steadily following marketing approval; however, their relative safety in nonvalvular atrial fibrillation (NVAF) patients in real-world clinical practice remains unclear.
OBJECTIVE
To compare the risk of major bleeding during anticoagulation therapy between warfarin and NOACs.
METHODS
This retrospective cohort study analyzed administrative claims data on new NVAF users of warfarin, dabigatran, apixaban, or rivaroxaban in routine clinical care from November 2010 to February 2015 in a commercially insured population in the United States. The primary outcome was time to first major bleeding event requiring hospitalization. Patients were followed until discontinuation or switch of anticoagulants, health plan disenrollment, death, or end of study. All patient characteristics were balanced after propensity score inverse probability of treatment (IPT) weighting. Event rates by type of anticoagulant exposure were compared using IPT-weighted Cox proportional hazards models.
RESULTS
The study cohort comprised 44,057 patients who used warfarin (n = 23,431), dabigatran (n = 8,539), apixaban (n = 3,689), and rivaroxaban (n = 8,398). Overall mean (SD) age was 70 (12) years, and 41% of the patients were women. A total of 2,337 major bleeding events occurred during 36,636.2 person-years of follow-up. The unadjusted rate of major bleeding with warfarin was 6.0 per 100 person-years versus 2.8 with dabigatran, 3.3 with apixban, and 5.0 with rivaroxaban. Relative to warfarin, major bleeding risk was lower with dabigatran (HR = 0.67, 95% CI = 0.60-0.76) and apixaban (HR = 0.52, 95% CI = 0.41-0.67). Compared with rivaroxaban, major bleeding risk was also lower with dabigatran (HR = 0.67, 95% CI = 0.58-0.78) and apixaban (HR = 0.52, 95% CI = 0.40-0.68). Major bleeding risk was similar for rivaroxaban and warfarin. Relative to apixaban, dabigatran was associated with a significantly higher risk of major gastrointestinal bleeding (HR = 1.43, 95% CI = 1.09-1.88).
CONCLUSIONS
Study results were consistent with safety findings from pivotal clinical trials comparing NOACs with warfarin and added the perspective of a large real-world observational study that compared bleeding risks associated with NOACs during anticoagulation therapy. Apixaban and dabigatran were associated with lower major bleeding risk compared with warfarin or rivaroxaban; however, apixaban had a lower risk of major gastrointestinal bleeding than dabigatran. These findings can help inform the choice of an optimal agent, which must balance effectiveness and bleeding risk in complex patients.
DISCLOSURES
This study was funded by Anthem. Adeboyeje, Sylwestrzak, and Barron are employees of HealthCore, a wholly owned and independently operated subsidiary of Anthem. White, Rosenberg, Abarca, and Crawford are employees of Anthem. Study concept and design were primarily contributed by Adeboyeje and Sylwestrzak, along with the other authors. Adeboyeje took the lead in data collection, along with Sylwestrzak and Barron. Data interpretation was performed primarily by Rosenberg, Crawford, and Redberg, with assistance from the other authors. The manuscript was written by all the authors and revised primarily by White, Abarca, and Redberg, along with the other authors.
View on PubMed2017
2017
2017
OBJECTIVES
Statins are recommended to reduce serum cholesterol in patients at risk for atherosclerotic cardiovascular disease. Despite the prevalence of statin use, little is known about the indications for new prescriptions. We assessed the concordance of new statin prescriptions in the Veterans Health Administration (VHA) compared with the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III, or ATP III) guidelines (the guidelines in force in 2012) and the American College of Cardiology (ACC)-American Heart Association (AHA) 2013 guidelines.
STUDY DESIGN
Cross-sectional study.
METHODS
We identified every patient who received a new prescription (no statin use in the prior year) in the VHA in 2012. Patients were excluded if they had incomplete data, triglycerides greater than 400 mg/dL, or fewer than 2 primary care visits to ensure adequate baseline data to calculate Framingham and ACC-AHA 2013 risk scores.
RESULTS
We identified 250,243 new statin prescriptions in 2012 in the VHA, with 121,081 meeting inclusion criteria. Among new prescriptions, 68% were prescribed for primary prevention and 32% were prescribed for secondary prevention. Among patients receiving new statins for primary prevention, 48% did not have an indication supported by the ATP III guideline and 20% did not have an indication supported by the ACC/AHA guideline. Overall, approximately 19% of patients may have received a statin for an indication not supported by either guideline.
CONCLUSIONS
Veterans are commonly prescribed statins for indications not supported by professional society guidelines. The finding of common use of statins outside established guidelines represents an opportunity to improve the quality and value of the healthcare delivery.
View on PubMed2017
2017
BACKGROUND AND OBJECTIVES
Breast milk is a complex bioactive fluid that varies across numerous maternal and environmental conditions. Although breast-feeding is known to affect neonatal gut microbiome, the milk components responsible for this effect are not well-characterized. Given the wide range of immunological activity breast milk cytokines engage in, we investigated 3 essential breast milk cytokines and their association with early life gut microbiota.
METHODS
A total of 52 maternal-child pairs were drawn from a racially diverse birth cohort based in Detroit, Michigan. Breast milk and neonatal stool specimens were collected at 1-month postpartum. Breast milk transforming growth factor (TGF)β1, TGFβ2, and IL-10 were assayed using enzyme-linked immunosorbent assays, whereas neonatal gut microbiome was profiled using 16S rRNA sequencing.
RESULTS
Individually, immunomodulators TGFβ1 and TGFβ2 were significantly associated with neonatal gut microbial composition (R = 0.024, P = 0.041; R = 0.026, P = 0.012, respectively) and increased richness, evenness, and diversity, but IL-10 was not. The effects of TGFβ1 and TGFβ2, however, were not independent of one another, and the effect of TGFβ2 was stronger than that of TGFβ1. Higher levels of TGFβ2 were associated with the increased relative abundance of several bacteria, including members of Streptococcaceae and Ruminococcaceae, and lower relative abundance of distinct Staphylococcaceae taxa.
CONCLUSIONS
Breast milk TGFβ concentration explains a portion of variability in gut bacterial microbiota composition among breast-fed neonates. Whether TGFβ acts in isolation or jointly with other bioactive components to alter bacterial composition requires further investigation. These findings contribute to an increased understanding of how breast-feeding affects the gut microbiome-and potentially immune development-in early life.
View on PubMed2017
2017
BACKGROUND
The prevalence of atrial fibrillation in the HIV-infected population is growing, but the ability of the CHA2DS2-VASc score to predict thromboembolic (TE) risk is unknown in this population.
SETTING
Within the Veterans Affairs HIV Clinical Case Registry, 914 patients had an atrial fibrillation diagnosis between 1997 and 2011 and no previous TE events.
METHODS
We compared TE incidence by CHA2DS2-VASc scores and stratified by warfarin use. Using Cox proportional hazards regression with adjustment for competing risks, we modeled associations of CHA2DS2-VASc scores and warfarin use with TE risk.
RESULTS
At baseline, the distribution of CHA2DS2-VASc scores was 0 (n = 208), 1 (n = 285), and 2+ (n = 421); 34 patients developed 38 TE events during a median of 3.8 years follow-up. Event rates by CHA2DS2-VASc scores of 0, 1, and 2+ were 5.4, 9.3, and 8.1 per 1000 person years, respectively; multivariate-adjusted hazards ratios (HRs) were 1.70 (95% confidence interval: 0.65 to 4.45) for CHA2DS2-VASc score 1 (P = 0.28) and HR = 1.34 (0.51, 3.48) for score 2+ versus 0 (P = 0.55). Baseline warfarin use was associated with increased TE risk, although not statistically significant [HR 2.06 (0.86, 4.93), P = 0.11] with similar results when modeled as time-updated use and duration of use.
CONCLUSION
In this national registry of HIV-infected veterans with atrial fibrillation, CHA2DS2-VASc scores were only weakly associated with TE risk. Furthermore, warfarin did not seem to be effective at preventing TE events. These results should raise concerns about the optimal strategy for TE prevention among HIV-infected persons with atrial fibrillation.
View on PubMed2017
Background
Osteopetrosis encompasses a group of rare metabolic bone diseases characterized by impaired osteoclast activity or development, resulting in high bone mineral density. Existing guidelines focus on treatment of the severe infantile forms with hematopoietic cell transplantation (HCT) but do not address the management of patients with less severe forms for whom HCT is not the standard of care. Therefore, our objective was to develop expert consensus guidelines for the management of these patients.
Methods
A modified Delphi method was used to build consensus among participants of the Osteopetrosis Working Group, with responses to an anonymous online survey used to identify areas of agreement and conflict and develop a follow-up survey. The strength of recommendations and quality of evidence was graded using the Grading of Recommendations Assessment, Development and Evaluation system.
Results
Consensus was found in the areas of diagnosis, monitoring, and treatment. We recommend relying on characteristic radiographic findings to make the diagnosis and found that genetic testing adds important information by identifying mutations associated with unique disease complications. We recommend ongoing monitoring for changes in mineral metabolism and other complications, including cranial nerve impingement, anemia, leukopenia, and dental disease. We suggest that calcitriol should not be used in high doses and instead recommend symptom-based supportive therapy for disease complications because noninfantile osteopetrosis has no effective treatment.
Conclusions
Scarcity of published studies on osteopetrosis reduce the ability to develop evidence-based guidelines for the management of these patients. Expert opinion-based guidelines for this rare condition are nevertheless important to enable improved care.
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