Publications by authors named "David Ferris"

Background: Both falls and fractures are increased in older persons living with HIV (PLWH). Low serum total 25-hydroxyvitamin D (25-OHD) levels have been associated with falls, fractures and poor muscle strength. We hypothesized that vitamin D (VitD) supplementation would improve muscle strength in postmenopausal PLWH.

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Background: The growing number of individuals with complex medical and social needs has motivated the adoption of care management (CM) - programs wherein multidisciplinary teams coordinate and monitor the clinical and non-clinical aspects of care for patients with chronic disease. Despite claims that health information technology (IT) is essential to CM, there has been limited research focused on the IT needs of clinicians providing care management to large groups of patients with chronic disease.

Objective: To assess clinicians' needs pertaining to CM and to identify inefficiencies and bottlenecks associated with the delivery of CM to large groups of patients with chronic disease.

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A large volcanic sulfate increase observed in ice core records around 1450 C.E. has been attributed in previous studies to a volcanic eruption from the submarine Kuwae caldera in Vanuatu.

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Background: With HIV-infected patients living longer, there is an increased burden of comorbidities related to aging, HIV itself, and polypharmacy. Cardiac morbidity is of particular importance.

Methods: This 2-group comparison study (156 HIV-positive and 105 HIV-negative patients) investigated the prevalence of abnormalities in and factors associated with an electrocardiogram (ECG) measure, corrected QT interval (QTc), where prolongation can lead to arrhythmia and sudden death.

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Background: Prevalence of osteoporosis and fracture is increased among older people with HIV. We compared the effects of low (1000 IU) vs moderate (3000 IU) vitamin D3 (VitD) supplementation on areal bone mineral density (aBMD) and volumetric bone mineral density (vBMD) in African American and Hispanic postmenopausal women with HIV on antiretroviral therapy.

Methods: We performed a 12-month prospective, randomized, double-blind, placebo-controlled study with primary outcomes of change in aBMD by dual-energy X-ray absorptiometry (DXA) and secondary outcomes of change in vBMD by quantitative computed tomography and bone turnover markers.

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A 300-year (1700-2007) chronological record of environmental perchlorate, reconstructed from high-resolution analysis of a central Greenland ice core, shows that perchlorate levels in the post-1980 atm were two-to-three times those of the pre-1980 environment. While this confirms recent reports of increased perchlorate in Arctic snow since 1980 compared with the levels for the prior decades (1930-1980), the longer Greenland record demonstrates that the Industrial Revolution and other human activities, which emitted large quantities of pollutants and contaminants, did not significantly impact environmental perchlorate, as perchlorate levels remained stable throughout the 18, 19, and much of the 20 centuries. The increased levels since 1980 likely result from enhanced atmospheric perchlorate production, rather than from direct release from perchlorate manufacturing and applications.

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Future precipitation changes in a warming climate depend regionally upon the response of natural climate modes to anthropogenic forcing. North Pacific hydroclimate is dominated by the Aleutian Low, a semi-permanent wintertime feature characterized by frequent low-pressure conditions that is influenced by tropical Pacific Ocean temperatures through the Pacific-North American (PNA) teleconnection pattern. Instrumental records show a recent increase in coastal Alaskan precipitation and Aleutian Low intensification, but are of insufficient length to accurately assess low frequency trends and forcing mechanisms.

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Objective: To characterize and compare cardiovascular disease (CVD) risk in HIV-infected and uninfected postmenopausal minority women using the Framingham Risk Score (FRS) as an assessment measure.

Methods: A cross-sectional analysis was performed in 152 (109 HIV+, 43 HIV-) subjects from an existing study cohort of postmenopausal Hispanic and African American women. Data necessary to calculate FRS and menopause features were retrieved by retrospective chart review.

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Importance: Substance use is a major driver of the HIV epidemic and is associated with poor HIV care outcomes. Patient navigation (care coordination with case management) and the use of financial incentives for achieving predetermined outcomes are interventions increasingly promoted to engage patients in substance use disorders treatment and HIV care, but there is little evidence for their efficacy in improving HIV-1 viral suppression rates.

Objective: To assess the effect of a structured patient navigation intervention with or without financial incentives to improve HIV-1 viral suppression rates among patients with elevated HIV-1 viral loads and substance use recruited as hospital inpatients.

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Background: HIV prevalence remains disproportionately high among youth, especially among young men who have sex with men, young people with substance use disorders, and recently incarcerated youth. However, youth may not report behavioral risks because they fear stigma or legal consequences. While routine HIV screening programs have increased testing, current programs are not designed to identify, or provide prevention services to, high-risk patients who test HIV negative.

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Our objective was to assess the effects of HIV infection and antiretroviral therapy on trabecular and cortical microarchitecture in postmenopausal minority women. A subgroup of 106 (46 HIV-infected, 60 uninfected) postmenopausal Hispanic and African American women from an established cohort had areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry and trabecular and cortical volumetric BMD (vBMD) and microarchitecture measured by high-resolution peripheral quantitative computed tomography (HRpQCT) at the radius and tibia. HIV-infected women were slightly younger (58 ± 1 vs.

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Cyanide is highly toxic and is present in many foods, combustion products (e.g. cigarette smoke), industrial processes, and has been used as a terrorist weapon.

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Context And Objective: The objective of the study was to assess the effects of HIV infection and antiretroviral therapy on change in bone mineral density (BMD) in postmenopausal minority women.

Design, Setting, And Patients: We report a longitudinal analysis of change in BMD with a median duration of 15.4 (interquartile range 13.

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Context: Low bone mineral density (BMD) is commonly reported in young men and women with HIV infection, and fracture rates may be higher. With effective antiretroviral therapy (ART), the HIV population is aging. However, little is known about the skeletal status of postmenopausal women.

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Textbooks are an expression of the state of development of a discipline at a given moment in time. By reviewing eight epidemiology textbooks published over the course of a century, we have attempted to trace the evolution of five epidemiologic concepts and methods: study design (cohort studies and case-control studies), confounding, bias, interaction and causal inference. Overall, these eight textbooks can be grouped into three generations.

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