Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2017
BACKGROUND & AIMS
The factors that distinguish metabolically healthy obesity from metabolically unhealthy obesity are not well understood. Diet has been implicated as a determinant of the unhealthy obesity phenotype, but which aspects of the diet induce dysmetabolism are unknown. The goal of this study was to investigate whether specific macronutrients or macronutrient combinations provoke dysmetabolism in the context of isocaloric, high-energy diets.
METHODS
Mice were fed 4 high-energy diets identical in calorie and nutrient content but different in nutrient composition for 3 weeks to 6 months. The test diets contained 42% carbohydrate (sucrose or starch) and 42% fat (oleate or palmitate). Weight and glucose tolerance were monitored; blood and tissues were collected for histology, gene expression, and immunophenotyping.
RESULTS
Mice gained weight on all 4 test diets but differed significantly in other metabolic outcomes. Animals fed the starch-oleate diet developed more severe hepatic steatosis than those on other formulas. Stable isotope incorporation showed that the excess hepatic steatosis in starch-oleate-fed mice derived from exaggerated adipose tissue lipolysis. In these mice, adipose tissue lipolysis coincided with adipocyte necrosis and inflammation. Notably, the liver and adipose tissue abnormalities provoked by starch-oleate feeding were reproduced when mice were fed a mixed-nutrient Western diet with 42% carbohydrate and 42% fat.
CONCLUSIONS
The macronutrient composition of the diet exerts a significant influence on metabolic outcome, independent of calories and nutrient proportions. Starch-oleate appears to cause hepatic steatosis by inducing progressive adipose tissue injury. Starch-oleate phenocopies the effect of a Western diet; consequently, it may provide clues to the mechanism whereby specific nutrients cause metabolically unhealthy obesity.
View on PubMed2017
BACKGROUND
Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is associated with significant morbidity and mortality. Similarities have been observed between patients with idiopathic pulmonary fibrosis (IPF) and the UIP (usual interstitial pneumonia) form of RA-ILD. The GAP (gender, age, physiology) model has been shown to predict mortality in patients with IPF, but its ability to predict mortality in RA-ILD is not known.
METHODS
We identified 309 patients with RA-ILD at 4 academic centers with ongoing longitudinal cohorts of patients with ILD. The primary endpoint was mortality. To handle missing data (n = 219 subjects with complete dataset), multiple imputation by iterative chained equations was used. Using the GAP model as a baseline, we assessed improvements in mortality risk prediction achieved by incorporating additional variables. Model discrimination was assessed using the c-index, and calibration was checked by comparing observed and expected incidence of death.
RESULTS
Patients had a mean age of 65 years and were predominantly female (54%). The mean forced vital capacity (FVC) % predicted was 73 and the mean diffusing capacity for carbon monoxide (DL) % predicted was 55. Twenty-four percent of the 236 patients with a high-resolution computed tomography scan available for review had a definite UIP pattern. The original GAP model, including gender, age, FVC%, and DL%, had a c-index of 0.746 in our cohort. Calibration of this model was satisfactory at 1, 2 and 3 years. Model discrimination was not meaningfully improved by adding other clinical variables.
CONCLUSION
The GAP model that was derived for IPF performs similarly as a mortality risk prediction tool in RA-ILD.
View on PubMed2017
BACKGROUND
Little is known about contraceptive care for the growing population of women veterans who receive care in the Veterans Administration (VA) healthcare system.
OBJECTIVE
To determine rates of contraceptive use, unmet need for prescription contraception, and unintended pregnancy among reproductive-aged women veterans.
DESIGN AND PARTICIPANTS
We conducted a cross-sectional, telephone-based survey with a national sample of 2302 women veterans aged 18-44 years who had received primary care in the VA within the prior 12 months.
MAIN MEASURES
Descriptive statistics were used to estimate rates of contraceptive use and unintended pregnancy in the total sample. We also estimated the unmet need for prescription contraception in the subset of women at risk for unintended pregnancy. For comparison, we calculated age-adjusted US population estimates using data from the 2011-2013 National Survey of Family Growth (NSFG).
KEY RESULTS
Overall, 62% of women veterans reported current use of contraception, compared to 68% of women in the age-adjusted US population. Among the subset of women at risk for unintended pregnancy, 27% of women veterans were not using prescription contraception, compared to 30% in the US population. Among women veterans, the annual unintended pregnancy rate was 26 per 1000 women; 37% of pregnancies were unintended. In the age-adjusted US population, the annual rate of unintended pregnancy was 34 per 1000 women; 35% of pregnancies were unintended.
CONCLUSIONS
While rates of contraceptive use, unmet contraceptive need, and unintended pregnancy among women veterans served by the VA are similar to those in the US population, these rates are suboptimal in both populations, with over a quarter of women who are at risk for unintended pregnancy not using prescription contraception, and unintended pregnancies accounting for over a third of all pregnancies. Efforts to improve contraceptive service delivery and to reduce unintended pregnancy are needed for both veteran and civilian populations.
View on PubMed2017
BACKGROUND
Substance use is highly prevalent among men who have sex with men (MSM) and is associated with individual-level sexual risk behaviors. However, few studies have explored the relationship between substance use and HIV risk behaviors within partnerships.
METHODS
We examined partner-level data between MSM participants (n=23) and their sexual partners (n=52). We used multivariable generalized estimating equations (GEE) logistic regression to assess the relationship between partner-level substance use during their last sexual encounter with each partner, and engaging in condomless anal intercourse (CAI) and serodiscordant CAI.
RESULTS
In multivariable analyses, participants had significantly higher adjusted odds ratio (AOR) of CAI when the participant (AOR=22.2, 95%CI=2.5-199.5) or their partners used any drugs (AOR=21.8, 95%CI=3.3-144.3); their partners (AOR=5.7, 95%CI=1.7-19.3) or both participant and partner had concordant use of methamphetamine (AOR=10.5, 95%CI=2.2-50.6); or when both used poppers (AOR=11.4, 95%CI=1.5-87). There were higher odds of SDCAI if the participant binge drank (AOR=4, 95%CI=1.01-15.8), used more than one substance (AOR=15.8, 95%CI=1.9-133), or used other drugs (AOR=4.8, 95%CI=1.3-18.4); if their partner used poppers (AOR=7.6, 95%CI=1.5-37.6), or used more than one substance (AOR=7.9, 95%CI=1.9-34.1); and when both participant and partner had concordant use of poppers (AOR=4.4, 95%CI=1.2-16.8).
CONCLUSIONS
This study observed significant relationship between substance use and HIV risk behaviors within partnerships. Specifically, when either the participant, the partner, or both used any drugs there was an increased odds of sexual risk behaviors. Findings suggest that partner-level substance use behaviors should be taken in account when developing sexual risk reduction interventions.
View on PubMed2017
2017
2017
2017
2017
BACKGROUND
Warfarin requires individualized dosing and monitoring in the ambulatory setting for protection against thromboembolic disease. Yet in multiple settings, patients spend upwards of 30% of time outside the therapeutic range, subjecting them to an increased risk of adverse events. At an urban, publicly funded clinic, the electronic health record (EHR) would not support integration with extant warfarin management software, which led to the creation and implementation of an electronic patient registry and a complementary team-based work flow to provide real-time health-system-level data for warfarin patients.
METHODS
Creation of the registry, which began in August 2014, entailed use of an existing platform, which could interface with the outpatient EHR. The registry was designed to help ensure regular testing and monitoring of patients while enabling identification of patients and subpopulations with suboptimal management. The work flow used for the clinic's warfarin patients was also redesigned. An assessment indicated that the registry identified 341 (96%) of 357 patients actively seen in the clinic.
RESULTS
For the cohort of the 357 patients in the registry, the no-show rate decreased from 31% (preimplementation, August 2014-December 2014) to 21% (postimplementation, January 2015-November 2015). The ratio of visits to no-shows increased from 2.3 to 4.0 visits.
CONCLUSION
Design and implementation of an electronic registry in conjunction with a complementary work flow established an active tracking system that improved treatment monitoring for patients on anticoagulation therapy. Registry creation also facilitated assessment of the quality of care and laid the groundwork for ongoing evaluation and quality improvement efforts.
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