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Study objectiveIn the Emergency Department (ED) setting, clinicians commonly treat severely elevated blood pressure (BP) despite the absence of evidence supporting this practice. We sought to determine if this rapid reduction of severely elevated BP in the ED has negative cerebrovascular effects.MethodsThis was a prospective quasi-experimental study occurring in an academic emergency department. The study was inclusive of patients with a systolic BP (SBP) > 180 mm Hg for whom the treating clinicians ordered intensive BP lowering with intravenous or short-acting oral agents. We excluded patients with clinical evidence of hypertensive emergency. We assessed cerebrovascular effects with measurements of middle cerebral artery flow velocities and any clinical neurological deterioration.ResultsThere were 39 patients, predominantly African American (90%) and male (67%) and with a mean age of 50 years. The mean pre-treatment SBP was 210 ± 26 mm Hg. The mean change in SBP was ?38 mm Hg (95% CI ?49 to ?27) mm Hg. The average change in cerebral mean flow velocity was ?5 (95% CI ?7 to ?2) cm/s, representing a ?9% (95% CI ?14% to ?4%) change. Two patients (5.1%, 95% CI 0.52–16.9%) had an adverse neurological event.ConclusionWhile this small cohort did not find an overall substantial change in cerebral blood flow, it demonstrated adverse cerebrovascular effects from rapid BP reduction in the emergency setting.  相似文献   
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Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security.  相似文献   
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Objective(s)

To examine the change in physical functional status among persons living with HIV (PLWH) in nursing homes (NHs) and how change varies with age and dementia.

Design

Retrospective cohort study.

Setting

NHs in 14 states in the United States.

Participants

PLWH who were admitted to NHs between 2001 and 2010 and had stays of ≥90 days (N = 3550).

Measurements

We linked Medicaid Analytic eXtract (MAX) and Minimum Data Set (MDS) data for NH residents in the sampled states and years and used them to determine HIV infection. The main outcome was improvement in physical functional status, defined as a decrease of at least 4 points in the activities of daily living (ADL) score within 90 days of NH admission. Independent variables of interest were age and dementia (Alzheimer's disease or other dementia). Multivariate logistic regression was used, adjusting for individual-level covariates.

Results

The average age on NH admission of PLWH was 58. Dementia prevalence ranged from 14.5% in the youngest age group (age <40 years) to 38.9% in the oldest group (age ≥70 years). Overall, 44% of the PLWH experienced ADL improvement in NHs. Controlling for covariates, dementia was related to a significantly lower likelihood of ADL improvement among PLWH in the oldest age group only: the adjusted probability of improvement was 40.6% among those without dementia and 29.3% among those with dementia (P < .01).

Conclusions/relevance

PLWH, especially younger persons, may be able to improve their ADL function after being admitted into NHs. However, with older age, PLWH with dementia are more physically dependent and vulnerable to deterioration of physical functioning in NHs. More and/or specialized care may be needed to maintain physical functioning among this population. Findings from this study provide NHs with information on care needs of PLWH and inform future research on developing interventions to improve care for PLWH in NHs.  相似文献   
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