Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2014
2014
OBJECTIVE
To delineate the association between baseline socioeconomic status (SES) indicators and mortality and lost to follow-up (LTFU) in a cohort of HIV-infected individuals enrolled in antiretroviral therapy (ART) in urban Uganda.
DESIGN
Retrospective cohort study nested in an antiretroviral clinic-based cohort.
METHODS
SES indicators including education, employment status, and a standardized wealth index, and other demographic and clinical variables were assessed at baseline among ART-treated patients in a clinic-based cohort in Kampala, Uganda. Confirmed mortality (primary outcome) and LTFU (secondary outcome) were actively ascertained over a 4-year follow-up period from 2005 to 2009.
RESULTS
Among 1763 adults [70.5% female; mean age, 36.2 years (SD = 8.4)] enrolled in ART, 14.4% (n = 253) were confirmed dead and 19.7% (n = 346) were LTFU at 4-year follow-up. No formal education [adjusted odds ratio (AOR) 1.76; 95% confidence interval (CI): 1.19 to 2.59], having fewer than 6 dependents (AOR 1.39; 95% CI: 1.04 to 1.86), unemployment (AOR 1.98; 95% CI: 1.48 to 2.66), and housing tenure index score (a component of the wealth index) (AOR 1.11; 95% CI: 1.00 to 1.23) were significantly associated with confirmed mortality at 4 years. SES indicators were not associated with LTFU at 4 years.
CONCLUSIONS
Baseline SES indicators, including education, number of dependents, employment status, and components of a standard wealth index may indicate long-term vulnerability to mortality in patients with HIV/AIDS, despite uniform access to ART. Future studies delineating the pathways through which poverty and limited assets affect clinical outcomes may lead to more effective HIV interventions in low-resource settings.
View on PubMed2014
BACKGROUND
Current recommendations for limits on metalworking fluids may provide insufficient protection from workplace-related illness. Chronic obstructive pulmonary disease (COPD) is a challenging outcome in occupational cohorts because its long period of worsening pulmonary function allows sicker workers to reduce exposure, causing a healthy worker survivor bias. G-estimation is a statistical method that reduces this bias. We introduce a public health approach using g-estimation to compare a series of potential exposure-reducing interventions.
METHODS
Autoworkers at three General Motors plants in Michigan were followed for COPD mortality from 1 January 1941 to 31 December 1994. For each of the three fluid types (straight, soluble, synthetic), a series of binary variables indicated whether exposure exceeded a series of potential limits. Separate g-estimation analyses for each limit yielded results expressed as the total number of years of life that could have been saved among those who died from COPD had that exposure limit been enforced.
RESULTS
Lower limits would have had greater effect than higher limits. A ban on soluble fluids (the most common type) would have had the greatest effect, saving an estimated 1550 years of life. Corresponding estimates were 737 and 260 years for straight and synthetic fluids, respectively. Few workers were exposed to synthetic fluids, limiting analytic power.
CONCLUSIONS
This application of g-estimation suggests that limiting exposure to metalworking fluids could have saved many years of life lost to COPD in this cohort. The approach permits comparison of different interventions. Separate limits should be considered for different types of fluids.
View on PubMed2014
OBJECTIVE
To compare educational and vocational outcomes among adults with childhood-onset systemic lupus erythematosus (SLE) and adult-onset SLE.
METHODS
We used data derived from the 2002–2010 cycles of the Lupus Outcomes Study, a longitudinal cohort of 1,204 adult subjects with SLE. Subjects ages 18–60 years living in the US (n = 929) were included in the analysis and were classified as childhood-onset SLE if age at diagnosis was <18 years (n = 115). Logistic regression was used to assess the unadjusted and adjusted effect of childhood-onset SLE, sex, race/ethnicity, baseline age, urban or rural location, and US region on the likelihood of completing a bachelor's degree. Generalized estimating equations were used to assess the effect of childhood-onset SLE, demographics, education, and disease-related factors on the odds of employment, accounting for multiple observations over the study period.
RESULTS
Subjects with childhood-onset SLE were on average younger (mean ± SD 29 ± 10 years versus 44 ± 9 years), with longer disease duration (mean ± SD 15 ± 10 years versus 11 ± 8 years). Subjects with adult-onset SLE and childhood-onset SLE subjects were equally likely to complete a bachelor's degree. However, subjects with childhood-onset SLE were significantly less likely to be employed, independent of demographic and disease characteristics (odds ratio 0.62, 95% confidence interval 0.42–0.91).
CONCLUSION
While subjects with SLE are just as likely as those with adult-onset SLE to complete college education, childhood-onset SLE significantly increases the risk of not working in adulthood, even when controlling for disease and demographic factors. Exploring reasons for low rates of employment and providing vocational support may be important to maximize long-term functional outcomes in patients with childhood-onset SLE.
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Matrix metalloproteinase-9 is elevated within the acutely injured murine spinal cord and blockade of this early proteolytic activity with GM6001, a broad-spectrum matrix metalloproteinase inhibitor, results in improved recovery after spinal cord injury. As matrix metalloproteinase-9 is likewise acutely elevated in dogs with naturally occurring spinal cord injuries, we evaluated efficacy of GM6001 solubilized in dimethyl sulfoxide in this second species. Safety and pharmacokinetic studies were conducted in naïve dogs. After confirming safety, subsequent pharmacokinetic analyses demonstrated that a 100 mg/kg subcutaneous dose of GM6001 resulted in plasma concentrations that peaked shortly after administration and were sustained for at least 4 days at levels that produced robust in vitro inhibition of matrix metalloproteinase-9. A randomized, blinded, placebo-controlled study was then conducted to assess efficacy of GM6001 given within 48 hours of spinal cord injury. Dogs were enrolled in 3 groups: GM6001 dissolved in dimethyl sulfoxide (n = 35), dimethyl sulfoxide (n = 37), or saline (n = 41). Matrix metalloproteinase activity was increased in the serum of injured dogs and GM6001 reduced this serum protease activity compared to the other two groups. To assess recovery, dogs were a priori stratified into a severely injured group and a mild-to-moderate injured group, using a Modified Frankel Scale. The Texas Spinal Cord Injury Score was then used to assess long-term motor/sensory function. In dogs with severe spinal cord injuries, those treated with saline had a mean motor score of 2 (95% CI 0-4.0) that was significantly (P<0.05; generalized linear model) less than the estimated mean motor score for dogs receiving dimethyl sulfoxide (mean, 5; 95% CI 2.0-8.0) or GM6001 (mean, 5; 95% CI 2.0-8.0). As there was no independent effect of GM6001, we attribute improved neurological outcomes to dimethyl sulfoxide, a pleotropic agent that may target diverse secondary pathogenic events that emerge in the acutely injured cord.
View on PubMed2014
BACKGROUND
Defining the association of non-AIDS-defining events with inflammation and immune activation among human immunodeficiency virus (HIV)-infected persons with antiretroviral therapy (ART)-associated virological suppression is critical to identifying interventions to decrease the occurrence of these events.
METHODS
We conducted a case-control study of HIV-infected subjects who had achieved virological suppression within 1 year after ART initiation. Cases were patients who experienced non-AIDS-defining events, defined as myocardial infarction, stroke, non-AIDS-defining cancer, non-AIDS-defining serious bacterial infection, or death. Controls were matched to cases on the basis of age, sex, pre-ART CD4(+) T-cell count, and ART regimen. Peripheral blood mononuclear cells and plasma specimens obtained at the visit before ART initiation (hereafter, baseline), the visit approximately 1 year after ART initiation (hereafter, year 1), and the visit immediately preceding the non-AIDS-defining event (hereafter, pre-event) were analyzed for activated CD4(+) and CD8(+) T cells, plasma interleukin 6 (IL-6) level, soluble tumor necrosis factor receptor I (sTNFR-I) level, sTNFR-II level, soluble CD14 level, kynurenine-to-tryptophan (KT) ratio, and D-dimer level. Conditional logistic regression analysis was used to study the association between biomarkers and outcomes, with adjustment for potential confounders.
RESULTS
Higher IL-6 level, sTNFR-I level, sTNFR-II level, KT ratio, and D-dimer level at year 1 were associated with the occurrence of a non-AIDS-defining event. Significant associations were also seen between non-AIDS-defining events and values of these biomarkers in specimens obtained at baseline and the pre-event time points. Effects remained significant after control for confounders. T-cell activation was not significantly related to outcomes.
CONCLUSIONS
Interventional trials to decrease the incidence of non-AIDS-defining events among HIV-infected persons with virological suppression should consider targeting the pathways represented by these soluble markers. Clinical Trials Registration. NCT00001137.
View on PubMed2014
Health disparities are prevalent across diseases of the respiratory system, and are major sources of morbidity and mortality among disadvantaged populations in the United States. The American Thoracic Society (ATS) aims to reduce disparities that are both avoidable and unjust. In meeting this goal, the ATS is committed to creating the Lung Corps, a diverse group of senior, mid-level, and junior clinicians, trainees, researchers, and public health practitioners to help achieve health equality. This will be achieved through the following mechanisms: (1) increase awareness of health disparities; (2) empower health professionals with the knowledge and tools to address disparities; (3) shape research agendas to focus on the root causes, to identify modifiable targets, and to promote innovative approaches to reduce disparities; and (4) develop and advocate for health-related policies and regulations that improve the respiratory health of the population. To ensure success, the Lung Corps will interact with other societies, agencies, and organizations to effect elimination of disparities in respiratory health. The ATS is committed to identifying and addressing health disparities to improve the overall health of individuals affected by respiratory diseases.
View on PubMed2014
Prostate cancer has surpassed lung cancer as the most common cancer in men in the United States. The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer based on clinical evidence and expert consensus. NCCN Panel guidance on treatment decisions for patients with localized disease is represented in this version. Significant updates for early disease include distinction between active surveillance and observation, a new section on principles of imaging, and revisions to radiation recommendations. The full version of these guidelines, including treatment of patients with advanced disease, can be found online at the NCCN website.
View on PubMed2014
Neuroendocrine prostate cancer (NEPC) encompasses various clinical contexts, ranging from the de novo presentation of small cell prostatic carcinoma to a treatment-emergent transformed phenotype that arises from typical adenocarcinoma of the prostate. The development of resistance to potent androgen receptor signaling inhibition may be associated with the emergence of aggressive phenotype, advanced castration-resistant NEPC. Clinically, small cell prostate cancer and NEPC are often manifested by the presence of visceral or large soft tissue metastatic disease, a disproportionately low serum prostate-specific antigen level relative to the overall burden of disease, and a limited response to targeting of the androgen signaling axis. These tumors are often characterized by loss of androgen receptor expression, loss of retinoblastoma tumor suppressor copy number or expression, amplification of Aurora kinase A and N-Myc, and activation of the PI3K pathway. However, a consensus phenotype-genotype definition of NEPC has yet to emerge, and molecularly based biomarkers are needed to expand on traditional morphologic and immunohistochemical markers of NEPC to fully define the spectrum of this aggressive, androgen receptor-independent disease. Emerging studies implicate a shared clonal origin with prostatic adenocarcinoma in many cases, with the adaptive emergence of unique cellular programming and gene expression profiles. Ongoing clinical studies are focused on developing novel targeted therapeutic approaches for this high-risk, lethal subset of disease, to improve on the limited durations of response often observed with traditional platinum-based chemotherapy.
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