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1.
Preprint in English | medRxiv | ID: ppmedrxiv-20134676

ABSTRACT

ObjectivesTo investigate whether there is a causal effect of cardiometabolic traits on risk of sepsis and severe covid-19. DesignMendelian randomisation analysis. SettingUK Biobank and HUNT study population-based cohorts for risk of sepsis, and genome-wide association study summary data for risk of severe covid-19 with respiratory failure. Participants12,455 sepsis cases (519,885 controls) and 1,610 severe covid-19 with respiratory failure cases (2,205 controls). ExposureGenetic variants that proxy body mass index (BMI), lipid traits, systolic blood pressure, lifetime smoking score, and type 2 diabetes liability - derived from studies considering between 188,577 to 898,130 participants. Main outcome measuresRisk of sepsis and severe covid-19 with respiratory failure. ResultsHigher genetically proxied BMI and lifetime smoking score were associated with increased risk of sepsis in both UK Biobank (BMI: odds ratio 1.38 per standard deviation increase, 95% confidence interval [CI] 1.27 to 1.51; smoking: odds ratio 2.81 per standard deviation increase, 95% CI 2.09-3.79) and HUNT (BMI: 1.41, 95% CI 1.18 to 1.69; smoking: 1.93, 95% CI 1.02-3.64). Higher genetically proxied BMI and lifetime smoking score were also associated with increased risk of severe covid-19, although with wider confidence intervals (BMI: 1.75, 95% CI 1.20 to 2.57; smoking: 3.94, 95% CI 1.13 to 13.75). There was limited evidence to support associations of genetically proxied lipid traits, systolic blood pressure or type 2 diabetes liability with risk of sepsis or severe covid-19. Similar findings were generally obtained when using Mendelian randomization methods that are more robust to the inclusion of pleiotropic variants, although the precision of estimates was reduced. ConclusionsOur findings support a causal effect of elevated BMI and smoking on risk of sepsis and severe covid-19. Clinical and public health interventions targeting obesity and smoking are likely to reduce sepsis and covid-19 related morbidity, along with the plethora of other health-related outcomes that these traits adversely affect. Summary boxesO_ST_ABSWhat is already known on this topicC_ST_ABSO_LISepsis and severe covid-19 are major contributors to global morbidity and mortality. C_LIO_LICardiometabolic risk factors have been associated with risk of sepsis and severe covid-19, but it is unclear if they are having causal effects. C_LI What this study addsO_LIUsing Mendelian randomization analyses, this study provides evidence to support that higher body mass index and lifetime smoking score both increase risk of sepsis and severe covid-19 with respiratory failure. C_LIO_LIClinical and public health interventions targeting obesity and smoking are likely to reduce sepsis and covid-19 related morbidity, along with the plethora of other health-related outcomes that these traits adversely affect. C_LI

2.
Preprint in English | medRxiv | ID: ppmedrxiv-20094797

ABSTRACT

BackgroundSARS-CoV-2 infection continues to cause significant morbidity and mortality worldwide. Preliminary data on SARS-CoV-2 infection suggests that some immunocompromised hosts experience worse outcomes. We performed a retrospective matched cohort study to characterize outcomes in HIV-positive patients with SARS-CoV-2 infection. MethodsLeveraging data collected from electronic medical records for all patients hospitalized at NYU Langone Health with COVID-19 between March 2, 2020 and April 23, 2020, we matched 21 HIV-positive patients to 42 non-HIV patients using a greedy nearest neighbor algorithm. Admission characteristics, laboratory results, and hospital outcomes were recorded and compared between the two groups. ResultsWhile there was a trend toward increased rates of ICU admission, mechanical ventilation, and mortality in HIV-positive patients, these differences were not statistically significant. Rates for these outcomes in our cohort are similar to those previously published for all patients hospitalized with COVID-19. HIV-positive patients had significantly higher admission and peak CRP values. Other inflammatory markers did not differ significantly between groups, though HIV-positive patients tended to have higher peak values during their clinical course. Three HIV-positive patients had superimposed bacterial pneumonia with positive sputum cultures, and all three patients expired during hospitalization. There was no difference in frequency of thrombotic events or myocardial infarction between these groups. ConclusionThis study provides evidence that HIV coinfection does not significantly impact presentation, hospital course, or outcomes of patients infected with SARS-CoV-2, when compared to matched non-HIV patients. A larger study is required to determine if the trends we observed apply to all HIV-positive patients.

3.
Preprint in English | medRxiv | ID: ppmedrxiv-20080036

ABSTRACT

BackgroundCOVID-19 has rapidly emerged as a pandemic infection that has caused significant mortality and economic losses. Potential therapies and means of prophylaxis against COVID-19 are urgently needed to combat this novel infection. As a result of in vitro evidence suggesting zinc sulfate may be efficacious against COVID-19, our hospitals began using zinc sulfate as add-on therapy to hydroxychloroquine and azithromycin. We performed a retrospective observational study to compare hospital outcomes among patients who received hydroxychloroquine and azithromycin plus zinc versus hydroxychloroquine and azithromycin alone. MethodsData was collected from electronic medical records for all patients being treated with admission dates ranging from March 2, 2020 through April 5, 2020. Initial clinical characteristics on presentation, medications given during the hospitalization, and hospital outcomes were recorded. Patients in the study were excluded if they were treated with other investigational medications. ResultsThe addition of zinc sulfate did not impact the length of hospitalization, duration of ventilation, or ICU duration. In univariate analyses, zinc sulfate increased the frequency of patients being discharged home, and decreased the need for ventilation, admission to the ICU, and mortality or transfer to hospice for patients who were never admitted to the ICU. After adjusting for the time at which zinc sulfate was added to our protocol, an increased frequency of being discharged home (OR 1.53, 95% CI 1.12-2.09) reduction in mortality or transfer to hospice remained significant (OR 0.449, 95% CI 0.271-0.744). ConclusionThis study provides the first in vivo evidence that zinc sulfate in combination with hydroxychloroquine may play a role in therapeutic management for COVID-19. 40-word summary: Zinc sulfate added to hydroxychloroquine and azithromycin may improve outcomes among hospitalized patients.

4.
J Neurol ; 267(2): 341-349, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31641878

ABSTRACT

OBJECTIVES: Progressive supranuclear palsy (PSP) is characterized by deposition of straight filament tau aggregates in the grey matter (GM) of deep nuclei and cerebellum. We examined the relationship between tau pathology (assessed via 18F-AV1451 PET) and multimodal MRI imaging using GM volume, cortical thickness (CTh), and diffusion tensor imaging (DTI). METHODS: Twenty-three people with clinically probable PSP-Richardson's syndrome (age 68.8 ± 5.8 years, 39% female) and 23 controls underwent structural 3 T brain MRI including DTI. Twenty-one patients also had 18F-AV1451 PET imaging. Voxelwise volume-based morphometry, surface-based morphometry, and DTI correlations were performed with 18F-AV1451 binding in typical PSP regions of interest (putamen, thalamus and dentate cerebellum). Clinical impairment was also assessed in relation to the different imaging modalities. RESULTS: PSP subjects showed GM volume loss in frontotemporal regions, basal ganglia, midbrain, and cerebellum (FDR-corrected p < 0.05), reduced CTh in the left entorhinal and fusiform gyrus (p < 0.001) as well as DTI changes in the corpus callosum, internal capsule, and superior longitudinal fasciculus (FWE-corrected p < 0.05). In PSP, higher 18F-AV1451 binding correlated with GM volume loss in frontal regions, DTI changes in motor tracts, and cortical thinning in parietooccipital areas. Cognitive impairment was related to decreased GM volume in frontotemporal regions, thalamus and pallidum, as well as DTI alteration in corpus callosum and cingulum. CONCLUSION: This cross-sectional study demonstrates an association between in vivo proxy measures of tau pathology and grey and white matter degeneration in PSP. This adds to the present literature about the complex interplay between structural changes and protein deposition.


Subject(s)
Gray Matter/diagnostic imaging , Magnetic Resonance Imaging , Positron-Emission Tomography , Supranuclear Palsy, Progressive/diagnostic imaging , White Matter/diagnostic imaging , tau Proteins/metabolism , Aged , Aged, 80 and over , Carbolines , Cross-Sectional Studies , Diffusion Tensor Imaging , Female , Gray Matter/metabolism , Gray Matter/pathology , Humans , Male , Middle Aged , Multimodal Imaging , Supranuclear Palsy, Progressive/metabolism , Supranuclear Palsy, Progressive/pathology , White Matter/pathology
5.
Brain ; 141(7): 2098-2111, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29746644

ABSTRACT

Modern ischaemic stroke management involves intravenous thrombolysis followed by mechanical thrombectomy, which allows markedly higher rates of recanalization and penumbral salvage than thrombolysis alone. However, <50% of treated patients eventually enjoy independent life. It is therefore important to identify complementary therapeutic targets. In rodent models, the salvaged penumbra is consistently affected by selective neuronal loss, which may hinder recovery by interfering with plastic processes, as well as by microglial activation, which may exacerbate neuronal death. However, whether the salvaged penumbra in man is similarly affected is still unclear. Here we determined whether these two processes affect the non-infarcted penumbra in man and, if so, whether they are inter-related. We prospectively recruited patients with (i) acute middle-cerebral artery stroke; (ii) penumbra present on CT perfusion obtained <4.5 h of stroke onset; and (iii) early neurological recovery as a marker of penumbral salvage. PET with 11C-flumazenil and 11C-PK11195, as well as MRI to map the final infarct, were obtained at predefined follow-up times. The presence of selective neuronal loss and microglial activation was determined voxel-wise within the MRI normal-appearing ipsilateral non-infarcted zone and surviving penumbra masks, and their inter-relationship was assessed both across and within patients. Dilated infarct contours were consistently excluded to control for partial volume effects. Across the 16 recruited patients, there was reduced 11C-flumazenil and increased 11C-PK11195 binding in the whole ipsilateral non-infarcted zone (P = 0.04 and 0.02, respectively). Within the non-infarcted penumbra, 11C-flumazenil was also reduced (P = 0.001), but without clear increase in 11C-PK11195 (P = 0.18). There was no significant correlation between 11C-flumazenil and 11C-PK11195 in either compartment. This mechanistic study provides direct evidence for the presence of both neuronal loss and microglial activation in the ipsilateral non-infarcted zone. Further, we demonstrate the presence of neuronal loss affecting the surviving penumbra, with no or only mild microglial activation, and no significant relationship between these two processes. Thus, microglial activation may not contribute to penumbral neuronal loss in man, and its presence in the ipsilateral hemisphere may merely reflect secondary remote degeneration. Selective neuronal loss in the surviving penumbra may represent a novel therapeutic target as an adjunct to penumbral salvage to further improve functional outcome. However, microglial activation may not stand as the primary therapeutic approach. Protecting the penumbra by acutely improving perfusion and oxygenation in conjunction with thrombectomy for example, may be a better approach. 11C-flumazenil PET would be useful to monitor the effects of such therapies.


Subject(s)
Infarction, Middle Cerebral Artery/physiopathology , Microglia/physiology , Neurons/physiology , Aged , Apoptosis , Brain Ischemia/complications , Brain Ischemia/diagnostic imaging , Female , Humans , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/diagnostic imaging , Macrophage Activation , Magnetic Resonance Imaging , Male , Middle Aged , Nervous System Malformations , Positron-Emission Tomography/methods
6.
Ann Clin Transl Neurol ; 3(12): 940-947, 2016 12.
Article in English | MEDLINE | ID: mdl-28097206

ABSTRACT

The validation of tau radioligands could improve the diagnosis of frontotemporal lobar degeneration and the assessment of disease-modifying therapies. Here, we demonstrate that binding of the tau radioligand [18F]AV-1451 was significantly abnormal in both magnitude and distribution in a patient with familial frontotemporal dementia due to a MAPT 10 + 16C>T gene mutation, recapitulating the pattern of neuropathology seen in her father. Given the genetic diagnosis and the non-Alzheimer's pathology, these findings suggest that [18F]AV-1451 might be a useful biomarker in primary tauopathies. Largerscale in vivo and post-mortem studies will be needed to assess the technique's specificity.

7.
Transl Psychiatry ; 5: e582, 2015 Jun 16.
Article in English | MEDLINE | ID: mdl-26080317

ABSTRACT

Though stimulant drugs such as cocaine are considered highly addictive, some individuals report recreational use over long periods without developing dependence. Difficulties in response inhibition have been hypothesized to contribute to dependence, but previous studies investigating response inhibition in recreational cocaine users have reported conflicting results. Performance on a stop-signal task was examined in 24 recreational cocaine users and 32 healthy non-drug using control participants matched for age, gender and verbal intelligence during functional magnetic resonance imaging scanning. The two groups were further matched on traumatic childhood histories and the absence of family histories of addiction. Results revealed that recreational cocaine users did not significantly differ from controls on any index of task performance, including response execution and stop-signal reaction time, with the latter averaging 198 ms in both groups. Functional magnetic resonance imaging analyses indicated that, compared with controls, stopping in the recreational users was associated with increased activation in the pre-supplementary motor area but not the right inferior frontal cortex. Thus, findings imply intact response inhibition abilities in recreational cocaine users, though the distinct pattern of accompanying activation suggests increased recruitment of brain areas implicated in response inhibition. This increased recruitment could be attributed to compensatory mechanisms that enable preserved cognitive control in this group, possibly relating to their hypothetical resilience to stimulant drug dependence. Such overactivation, alternatively, may be attributable to prolonged cocaine use leading to neuroplastic adaptations.


Subject(s)
Cocaine-Related Disorders/psychology , Executive Function/physiology , Inhibition, Psychological , Motor Cortex/physiopathology , Prefrontal Cortex/physiopathology , Adult , Brain/physiopathology , Case-Control Studies , Central Nervous System Stimulants , Cocaine , Cocaine-Related Disorders/physiopathology , Female , Frontal Lobe/physiopathology , Functional Neuroimaging , Humans , Magnetic Resonance Imaging , Male , Reaction Time , Task Performance and Analysis , Young Adult
8.
Biol Psychiatry ; 75(2): 124-31, 2014 Jan 15.
Article in English | MEDLINE | ID: mdl-23809860

ABSTRACT

BACKGROUND: Although cocaine is known to be a highly addictive drug, there appears to be a select subset of individuals who are able to use the substance recreationally without developing dependence. These individuals do not report experiencing feelings of craving for cocaine, an important distinction from dependent users. However, no prior studies have compared attentional bias with cocaine cues between these groups to confirm this difference. Additionally, previous investigations into cognitive abilities in these individuals have been conflicting, and no research has been conducted on the neurobiological processes underlying cognitive functioning in this group. METHODS: This study administered the emotional cocaine-word Stroop to 27 recreational cocaine users, 50 stimulant-dependent individuals, and 52 healthy control participants during functional magnetic resonance imaging scanning. Behavioral and functional imaging results were compared between groups to assess attentional bias and cognitive effort to resist salient cocaine stimuli. RESULTS: Recreational users did not exhibit attentional bias to the cocaine words and did not differ from control subjects on task performance. Conversely, stimulant-dependent individuals were significantly more impaired on the task. Recreational participants also displayed a unique pattern of activation during performance, with significant underactivation in the orbitofrontal and anterior cingulate cortices compared with both dependent users and control subjects. CONCLUSIONS: The absence of bias to cocaine-related stimuli in recreational users indicates they do not share attentional preference for these words with dependent users. Their distinct pattern of activation suggests a decreased need for cognitive control due to diminished desire for the drug, potentially serving as a resilience factor against dependence.


Subject(s)
Attention/physiology , Cocaine-Related Disorders/physiopathology , Cocaine-Related Disorders/psychology , Cocaine/adverse effects , Cues , Drug Users/psychology , Frontal Lobe/physiopathology , Adult , Behavior, Addictive/physiopathology , Behavior, Addictive/psychology , Female , Functional Neuroimaging , Humans , Magnetic Resonance Imaging , Male , Stroop Test , Young Adult
9.
Neuropsychopharmacology ; 38(10): 1945-53, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23609131

ABSTRACT

A neurocognitive endophenotype has been proposed for stimulant dependence, based on behavioral measures of inhibitory response control associated with white matter changes in the frontal cortex. This study investigated the functional neuroimaging correlates of inhibitory response control, as functional activity serves as a more dynamic measure than brain structure, allowing refinement of the suggested endophenotype. Stimulant-dependent individuals (SDIs), their unaffected siblings (SIBs), and healthy controls (CTs) performed the stop-signal task, including stop-signal reaction time (SSRT) as a measure of response inhibition, while undergoing functional magnetic resonance imaging. SDIs had impaired response inhibition accompanied by hypoactivation in the ventrolateral prefrontal cortex (PFC). In addition, they demonstrated hypoactivation in the anterior cingulate when failing to stop. In contrast, no hypoactivations were noted in their unaffected SIBs. Rather, they exhibited increased activation in the dorsomedial PFC relative to controls, together with inhibitory performance that was intermediate between that of the stimulant group and the healthy CT group. Such hyperactivations within the neurocircuitry underlying response inhibition and control are suggestive of compensatory mechanisms that could be protective in nature or could reflect coping with a pre-existing vulnerability, thus expressing potential aspects of resilience. The functional activation associated with response inhibition and error monitoring showed differential patterns of results between SDIs and their unaffected first-degree relatives, suggesting that the proposed endophenotype does not generalize to functional brain activity.


Subject(s)
Amphetamine-Related Disorders/physiopathology , Cocaine-Related Disorders/physiopathology , Gyrus Cinguli/physiopathology , Inhibition, Psychological , Prefrontal Cortex/physiopathology , Siblings/psychology , Adult , Brain Mapping , Case-Control Studies , Endophenotypes , Female , Humans , Male , Psychomotor Performance/physiology
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