Unveiling the Burden of Miscoding and Misclassification in Stroke Mortality: Analysis of Multiple Cause-of-Death Data in Mexico.

BACKGROUND: The prevalence of risk factors for cerebrovascular diseases in Mexico is increasing although stroke mortality declined from 1990 to 2010, without meaningful changes afterward. While improving access to adequate prevention and care could explain this trend, miscoding and misclassification in death certificates need to be assessed to unveil the true burden of stroke in Mexico. Practices in death certification along with the presence of multi-morbidity could contribute to this distortion. Analyses of multiple causes of death could reveal ill-defined stroke deaths, providing a glimpse of this bias. METHODS: Cause-of-death information from 4,262,666 death certificates in Mexico from 2009 to 2015, was examined to determine the extent of miscoding and misclassification on the true burden of stroke. Age-standardized mortality rates per 100,000 inhabitants (ASMR) were calculated for stroke as underlying and multiple causes of death, by sex and state. Deaths were classified following international standards as ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and unspecified, which were kept as an independent category to measure miscoding. To approximate misclassification, we compared ASMR under three misclassification scenarios: (1) current (the status quo); (2) moderate, which includes deaths from selected causes mentioning stroke; and (3) high which includes all deaths mentioning stroke. National and subnational data were analyzed to search for geographical patterns. RESULTS: The burden of stroke in Mexico is underreported due to miscoding and misclassification. Miscoding is an important issue since almost 60% of all stroke deaths are registered as unspecified. Multiple cause analysis indicates that stroke ASMR could increase 39.9%-52.9% of the current ASMR under moderate and high misclassification scenarios, respectively. Both problems indicate the need to improve death codification procedures and cause-of-death classification. CONCLUSIONS: Miscoding and misclassification lead to underestimation of the burden of stroke in Mexico. Stroke deaths are underreported when other important causes coexist, being diabetes the most frequent.

Predictors of Mechanical Ventilation in Guillain-Barré Syndrome with Axonal Subtypes.

BACKGROUND: The early clinical predictors of respiratory failure in Latin Americans with Guillain-Barré syndrome (GBS) have scarcely been studied. This is of particular importance since Latin America has a high frequency of axonal GBS variants that may imply a worse prognosis. METHODS: We studied 86 Mexican patients with GBS admitted to the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, a referral center of Mexico City, to describe predictors of invasive mechanical ventilation (IMV). RESULTS: The median age was 40 years (interquartile range: 26-53.5), with 60.5% men (male-to-female ratio: 1.53). Most patients (65%) had an infectious antecedent (40.6% gastrointestinal). At admission, 38% of patients had a Medical Research Council (MRC) sum score <30. Axonal subtypes predominated (60.5%), with acute motor axonal neuropathy being the most prevalent (34.9%), followed by acute inflammatory demyelinating polyneuropathy (32.6%), acute motor sensory axonal neuropathy (AMSAN) (25.6%), and Fisher syndrome (7%). Notably, 15.1% had onset in upper limbs, 75.6% dysautonomia, and 73.3% pain. In all, 86% received either IVIg (9.3%) or plasma exchange (74.4%). IMV was required in 39.5% patients (72.7% in AMSAN). A multivariate model without including published prognostic scores yielded the time since onset to admission <15 days, axonal variants, MRC sum score <30, and bulbar weakness as independent predictors of IMV. The model including grading scales yielded lower limbs onset, Erasmus GBS respiratory insufficiency score (EGRIS) >4, and dysautonomia as predictors. CONCLUSION: These results suggest that EGRIS is a good prognosticator of IMV in GBS patients with a predominance of axonal electrophysiological subtypes, but other early clinical data should also be considered.

Osmotic demyelination syndrome in patients with non-Hodgkin lymphoma: a case report and literature review.

INTRODUCTION: Osmotic demyelination syndrome (ODS) is a non-inflammatory process of the central nervous system caused by extracellular osmotic changes, which leads to oligodendrocyte apoptosis and disruption of myelin sheaths, usually affecting patients with underlying systemic conditions that impose susceptibility to osmotic stress. Description of ODS in patients with non-Hodgkin lymphoma (NHL) is limited to a few case reports. METHODS: Here, we report a 44-year-old man with NHL that had an incidental diagnosis of ODS. We conducted a literature review of the published cases of ODS in NHL patients from 1959 to 2020, aiming to describe the characteristics of these patients. RESULTS: A total of seven patients were summarized (four men and three women), including our case and six patients from published reports. Risk factors such as weight loss and alcoholism were reported in five (71.4%) patients. Hyponatremia was found in six (85.7%) of the cases, and none of them had overly rapid sodium correction. Four cases were asymptomatic, and diffuse large B-cell lymphoma was the most common subtype of NHL (85.7%). The outcome was favorable in most cases; only two deaths not directly related to ODS were reported. CONCLUSION: We wish to suggest that systemic and metabolic stress induced by NHL may be associated with the development of central osmotic demyelination, and therefore, NHL may be a novel risk factor for ODS. Clinicians should be aware of ODS in patients with hematological malignancies, even in the absence of traditional risk factors.

Optogenetic and Chemogenic Control of Pain Signaling: Molecular Markers.

Pain is a complex experience that involves physical, emotional, and cognitive aspects. This review focuses specifically on the physiological processes underlying pain perception, with a particular emphasis on the various types of sensory neurons involved in transmitting pain signals to the central nervous system. Recent advances in techniques like optogenetics and chemogenetics have allowed researchers to selectively activate or inactivate specific neuronal circuits, offering a promising avenue for developing more effective pain management strategies. The article delves into the molecular targets of different types of sensory fibers such as channels, for example, TRPV1 in C-peptidergic fiber, TRPA1 in C-non-peptidergic receptors expressed differentially as MOR and DOR, and transcription factors, and their colocalization with the vesicular transporter of glutamate, which enable researchers to identify specific subtypes of neurons within the pain pathway and allows for selective transfection and expression of opsins to modulate their activity.

Antiphospholipid syndrome-mediated acute cerebrovascular diseases and long-term outcomes.

OBJECTIVES: The antiphospholipid syndrome (APS) is an autoimmune disease associated with thrombotic and non-thrombotic neurologic manifestations. APS is classified as primary (PAPS) or secondary (SAPS) when it co-exists with another autoimmune disease. We aim to describe the spectrum of acute cerebrovascular disease among patients with APS, their differences between stroke subtypes, and long-term functional outcomes. METHODS: Retrospective cohort study including adult (≥18 years) patients with APS followed in the stroke clinic of a tertiary-care reference center for autoimmune diseases in Mexico from 2009 to 2019. RESULTS: We studied 120 cases; 99 (82.5%) women; median age 43 years (interquartile range 35-52); 63.3% with SAPS. Demographics, comorbidities, and antiphospholipid antibodies (aPL) positivity were similar between APS type and stroke subtypes. Amongst index events, we observed 84 (70%) acute ischemic strokes (AIS), 19 (15.8%) cerebral venous thromboses (CVT), 11 (9.2%) intracerebral hemorrhages (ICH), and six (5%) subarachnoid hemorrhages (SAH). Sixty-seven (55.8%) were known patients with APS; the median time from APS diagnosis to index stroke was 46 months (interquartile range 12-96); 64.7% of intracranial hemorrhages (ICH or SAH) occurred ≥4 years after APS was diagnosed (23.5% anticoagulation-related); 63.2% of CVT cases developed before APS was diagnosed or simultaneously. Recurrences occurred in 26 (22.8%) patients, AIS, in 18 (69.2%); intracranial hemorrhage, in eight (30.8%). Long-term functional outcomes were good (modified Rankin Scale ≤2) in 63.2% of cases, during follow-up, the all-cause mortality rate was 19.2%. CONCLUSION: We found no differences between stroke subtypes and APS types. aPL profiles were not associated with any of the acute cerebrovascular diseases described in this cohort. CVT may be an initial thrombotic manifestation of APS with low mortality and good long-term functional outcome.

Incidence of Guillain-Barré syndrome following SARS-CoV-2 immunization: Analysis of a nationwide registry of recipients of 81 million doses of seven vaccines.

BACKGROUND AND PURPOSE: Information on Guillain-Barré syndrome (GBS) as an adverse event following immunization (AEFI) against SARS-CoV-2 remains scarce. We aimed to report GBS incidence as an AEFI among adult (≥18 years) recipients of 81,842,426 doses of seven anti-SARS-CoV-2 vaccines between December 24, 2020, and October 29, 2021, in Mexico. METHODS: Cases were retrospectively collected through passive epidemiological surveillance. The overall observed incidence was calculated according to the total number of administered doses. Vaccines were analyzed individually and by vector as mRNA-based (mRNA-1273 and BNT162b2), adenovirus-vectored (ChAdOx1 nCov-19, rAd26-rAd5, Ad5-nCoV, and Ad26.COV2-S), and inactivated whole-virion-vectored (CoronaVac) vaccines. RESULTS: We identified 97 patients (52 males [53.6%]; median [interquartile range] age 44 [33-60] years), for an overall observed incidence of 1.19/1,000,000 doses (95% confidence interval [CI] 0.97-1.45), with incidence higher among Ad26.COV2-S (3.86/1,000,000 doses, 95% CI 1.50-9.93) and BNT162b2 recipients (1.92/1,00,000 doses, 95% CI 1.36-2.71). The interval (interquartile range) from vaccination to GBS symptom onset was 10 (3-17) days. Preceding diarrhea was reported in 21 patients (21.6%) and mild COVID-19 in four more (4.1%). Only 18 patients were tested for Campylobacter jejuni (positive in 16 [88.9%]). Electrophysiological examinations were performed in 76 patients (78.4%; axonal in 46 [60.5%] and demyelinating in 25 [32.8%]); variants were similar across the platforms. On admission, 91.8% had a GBS disability score ≥3. Seventy-five patients (77.3%) received intravenous immunoglobulin, received seven plasma exchange (7.2%), and 15 (15.5%) were treated conservatively. Ten patients (10.3%) died, and 79.1% of survivors were unable to walk independently. CONCLUSIONS: Guillain-Barré syndrome was an extremely infrequent AEFI against SARS-CoV-2. The protection provided by these vaccines outweighs the risk of developing GBS.

Critical role of acute hypoxemia on the cognitive impairment after severe COVID-19 pneumonia: a multivariate causality model analysis.

BACKGROUND: A high proportion of coronavirus disease 2019 (COVID-19) survivors may develop long-term cognitive impairment. We aimed to develop a multivariate causal model exposing the links between COVID-19-associated biomarkers, illness-related variables, and their effects on cognitive performance. METHODS: In this prospective study, we assess the potential drivers for the development of cognitive impairment in patients with severe COVID-19 pneumonia aged ≥ 18 years at 6-month follow-up after hospital discharge, using the Montreal Cognitive Assessment (MoCA). Patients with pre-existing cognitive impairment were excluded. Laboratory results at hospital admission were clustered by principal component analysis (PCA) and included in a path analysis model evaluating the causal relationship between age, comorbidities, hypoxemia, invasive mechanical ventilation (IMV) requirement, in-hospital delirium, and cognitive performance. RESULTS: We studied 92 patients: 54 (58.7%) men and 38 (41.3%) women, with median age of 50 years (interquartile range 42-55), among whom 50 (54.4%) tested positive for cognitive impairment at 6-month follow-up. Path analysis revealed a direct link between the thrombo-inflammatory component of PCA (C-reactive protein, fibrinogen, and neutrophils) and hypoxemia severity at hospital admission. Our model showed that low PaO2/FiO2 ratio values, unlike the thrombo-inflammatory component, had a direct effect on cognitive performance, independent from age, in-hospital delirium, and invasive mechanical ventilation. CONCLUSION: In this study, biomarkers of thrombo-inflammation in COVID-19 and low PaO2/FiO2 had a negative effect on cognitive performance 6 months after hospital discharge. These results highlight the critical role of hypoxemia as a driver for impaired cognition in the mid-term.

Headache related to personal protective equipment in healthcare workers during COVID-19 pandemic in Mexico: baseline and 6-month follow-up.

BACKGROUND AND AIM: Headaches related to the use of personal protective equipment (PPE) could affect performance at work in healthcare personnel. Our aim was to describe the prevalence and risk factors for headaches related to PPE, in the personnel of a specialized coronavirus disease 2019 (COVID-19) tertiary hospital. METHODS: In this cross-sectional survey study, we invited healthcare workers from COVID-19 referral center in Mexico (May 22-June 19, 2020) to answer a standardized structure questionnaire on characteristics of new-onset PPE-related headache or exacerbation of primary headache disorder. Participants were invited regardless of whether they had a current headache to avoid selection bias. This is the primary analysis of these data. RESULTS: Two hundred and sixty-eight subjects were analyzed, 181/268 (67.5%) women, 177/268 (66%) nurses, mean age 28 years. The prevalence of PPE-related headache was 210/268 (78.4%). Independent risk factors were occupation other than physician (OR 1.59, 95% CI 1.20-2.10), age > 30 years (OR 2.54, 95% CI 1.25-5.14), and female sex (OR 3.58, 95% CI 1.86-6.87). In the 6-month follow-up, 13.1% of subjects evolve to chronic headache, with stress as predictive risk factor. CONCLUSION: The frequency of PPE-associated headache is high, and a subgroup could evolve to chronic headache. More studies are necessary to improve the knowledge about this condition.

COVID-19-related diffuse posthypoxic leukoencephalopathy and microbleeds masquerades as acute necrotizing encephalopathy.

BACKGROUND: The complications of coronavirus disease 2019 (COVID-19), the clinical entity caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are not limited to the respiratory system. Leukoencephalopathy with microbleeds is increasingly seen in patients with COVID-19. New information is needed to delineate better the clinical implications of this infectious disease. CASE REPORT: A 46-year-old man with confirmed SARS-CoV-2 infection was admitted to the intensive care unit (ICU) with severe COVID-19. After transfer to the general wards, the patient was noted drowsy, disorientated, with slow thinking and speech. A brain MRI showed bilateral symmetrical hyperintense lesions in the deep and subcortical whiter matter, involving the splenium of the corpus callosum, as well as multiple microhemorrhages implicating the splenium and subcortical white matter. No contrast-enhanced lesions were observed in brain CT or MRI. CSF analysis showed no abnormalities, including a negative rtRT-PCR for SARS-CoV-2. An outpatient follow-up visit showed near-complete clinical recovery and resolution of the hyperintense lesions on MRI, without microbleeds change. CONCLUSION: We present the case of a survivor of severe COVID-19 who presented diffuse posthypoxic leukoencephalopathy, and microbleeds masquerading as acute necrotizing encephalopathy. We postulate that this kind of cerebral vasogenic edema with microbleeds could be the consequence of hypoxia, inflammation, the prothrombotic state and medical interventions such as mechanical ventilation and anticoagulation.

Hospital Arrival and Functional Outcome after Intracerebral Hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is associated with an ominous outcome influenced by the time to hospital presentation. OBJECTIVE: This study aims to identify the factors that influence an early hospital arrival after ICH and the relationship with outcome. METHODS: In this multicenter registry, patients with confirmed ICH on CT scan and well-known time of symptoms onset were studied. Clinical data, arrival conditions, and prognostic scores were analyzed. Multivariate models were built to find independent predictors of < 6 h arrival (logistic regression) and in-hospital death (Cox proportional-hazards model). RESULTS: Among the 473 patients analyzed (51% women, median age 63 years), the median delay since onset to admission was 6.25 h (interquartile range: 2.5-24 h); 7.8% arrived in < 1 h, 26.3% in < 3 h, 45.3% in < 6 h, and 62.3% in < 12 h. The in-hospital, 30-day and 90-day case fatality rates were 28.8%, 30.0%, and 32.6%, respectively. Predictors of arrival in < 6 h were hypertension treatment (odds ratios [OR]: 1.675, 95% confidence intervals [CI]: 1.030-2.724), ≥ 3 years of schooling (OR: 1.804, 95% CI: 1.055-3.084), and seizures at ICH onset (OR: 2.416, 95% CI: 1.068-5.465). Predictors of death (56.9% neurological) were systolic blood pressure > 180 mmHg (hazards ratios [HR]: 1.839, 95% CI: 1.031-3.281), ICH score ≥ 3 (HR: 2.302, 95% CI: 1.300-4.074), and admission Glasgow Coma Scale < 8 (HR: 4.497, 95% CI: 2.466-8.199). Early arrival was not associated with outcome at discharge, 30 or 90 days. CONCLUSIONS: In this study, less than half of patients with ICH arrived to the hospital in < 6 h. However, early arrival was not associated with the short-term outcome in this data set.

Prediction of acute neurovascular syndromes with prehospital clinical features witnessed by bystanders.

BACKGROUND: The prompt recognition of an acute neurovascular syndrome by the patient or a bystander witnessing the event can directly influence outcome. We aimed to study the predictive value of the medical history and clinical features recognized by the patients' bystanders to preclassify acute stroke syndromes in prehospital settings. METHODS: We analyzed 369 patients: 209 (56.6%) with acute ischemic stroke (AIS), 107 (29.0%) with intracerebral hemorrhage (ICH), and 53 (14.4%) with subarachnoid hemorrhage (SAH). All patients had neuroimaging as diagnostic gold standard. We constructed clinical prediction rules (CPRs) with features recognized by the bystanders witnessing the stroke onset to classify the acute neurovascular syndromes before final arrival to the emergency room (ER). RESULTS: In all, 83.2% cases were referred from other centers, and only 16.8% (17.2% in AIS, 15% in ICH, and 18.9% in SAH) had direct ER arrival. The time to first assessment in ≤ 3 h occurred in 72.4% (73.7%, 73.8%, and 64.2%, respectively), and final ER arrival in ≤ 3 h occurred in 26.8% (32.1%, 15.9%, and 28.3%, respectively). Clinical features referred by witnesses had low positive predictive values (PPVs) for stroke type prediction. Language or speech disorder + focal motor deficit showed 63.3% PPV, and 77.0% negative predictive value (NPV) for predicting AIS. Focal motor deficit + history of hypertension had 35.9% PPV and 78.8% NPV for ICH. Headache alone had 27.9% PPV and 95.3% NPV for SAH. In multivariate analyses, seizures, focal motor deficit, and hypertension increased the probability of a time to first assessment in ≤ 3 h, while obesity was inversely associated. Final ER arrival was determined by age and a direct ER arrival without previous referrals. CONCLUSION: CPRs constructed with the witnesses' narrative had only adequate NPVs in the prehospital classification of acute neurovascular syndromes, before neuroimaging confirmation.

Peripheral artery disease in outpatients with a recent history of acute coronary syndrome or at high atherothrombotic risk.

OBJECTIVES: The frequency and implications of peripheral artery disease (PAD) in some risk groups are not entirely characterized in Latin America. We studied PAD prevalence, risk factors, and six-month outcomes in stable outpatients with a history of a recent acute coronary syndrome (ACS), or at high coronary risk. METHODS: We recruited 830 outpatients in 43 Mexican sites (median age: 64.8 years; 57.8% men). Inclusion criteria were age >18 years, and ACS within 30 days, or age <55 years plus ≥2 major vascular risk factors, or age ≥55 years plus ≥1 vascular risk factors. Patients received standardized assessments at baseline and six-month follow-up for medical history, ankle-brachial index (ABI), and the Edinburgh Claudication Questionnaire (ECQ). RESULTS: ABI <0.8 was found in 10.5%, <0.9 in 22.5%, >1.3 in 4.8%, and >1.4 in 3.6%, without differences according to sex or selection criteria. Positive ECQ was found in 7.6%. ABI <0.9 was directly associated with age, diabetes, ACS, and chronic kidney disease, but inversely associated with BMI >27. The six-month case-fatality and atherothrombotic events rates were 1.6% and 3.6%, respectively. In patients with ABI <0.9 and ABI <0.8, the six-month case-fatality rates were 2.5% (p = 0.27) and 5.4% (p = 0.03), respectively. In a Cox proportional-hazards model, baseline factors associated with death were age ≥65, ABI <0.8, and ACS. CONCLUSIONS: Subclinical PAD is more common than symptomatic claudication in high-risk coronary outpatients. Low ABI is associated with reduced short-term survival in patients with recent ACS or at high coronary risk.

Detection of Pulmonary Shunts by Transcranial Doppler in Hospitalized Non-mechanically Ventilated Coronavirus Disease-19 Patients.

In severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated disease coronavirus disease 2019 (COVID-19), hypoxemia mechanisms differ from those observed in acute respiratory distress syndrome. Hypoxemia and respiratory failure in COVID- 19 are attributed to pulmonary angiopathy, increasing physiological pulmonary shunting1-3.

Clinical and neurophysiological description of patients with POEMS syndrome.

INTRODUCTION: POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a monoclonal gammopathy with polyneuropathy as a mandatory criterion. OBJECTIVE: To describe potential associations between clinical expression and electrodiagnostic patterns in POEMS syndrome. METHOD: Observational, retrospective, cross-sectional study of cases cared for in a referral center, diagnosed with POEMS syndrome from 2009 to 2019. RESULTS: Eleven patients (8 men) were analyzed. Median age at diagnosis was 40 years (range: 31-51; mean: 37.19 ± 15.67 years). Mean latency at diagnosis was 9.7 ± 8.37 months. In all subjects, initial clinical manifestation was polyneuropathy. Most patients had an axonal pattern (n = 5), followed by demyelinating (n = 4) and mixed patterns (n = 2). Monoclonal gammopathy was observed in all (6 l and 5 k cases; immunoglobulin [Ig] G: 72 %; IgA: 18 %; IgM: 9 %). Medical Research Council sum score was lower in the axonal pattern (median: 37.00 vs. 45.5; p = 0.024). There were no differences in systemic involvement between electrophysiological patterns. CONCLUSION: Electrophysiological patterns are unlikely to have a clear extra-neurological clinical correspondence; however, this will have to be definitively proven with a larger sample size.

INTRODUCCIÓN: El síndrome POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) es una gammapatía monoclonal con polineuropatía como criterio obligatorio. OBJETIVO: Describir las potenciales asociaciones entre la expresión clínica y los patrones de electrodiagnóstico en el síndrome POEMS. MÉTODO: Estudio observacional, retrospectivo y transversal de los casos atendidos en un centro de referencia con diagnóstico de síndrome de POEMS de 2009 a 2019. RESULTADOS: Se analizó a 11 pacientes (8 hombres). La mediana de la edad al diagnóstico fue de 40 años (rango: 31-51, media: 37.19 ± 15.67 años). La latencia media al diagnóstico fue de 9.7 ± 8.37 meses. En todos la manifestación clínica inicial fue la polineuropatía. La mayoría de los pacientes presentaron un patrón axonal (n = 5), seguido del desmielinizante (n = 4) y mixto (n = 2). La gammapatía monoclonal se observó en todos (6 casos l y 5 k, inmunoglobulina [Ig] G: 72%, IgA: 18%, IgM: 9%). El Medical Research Council sum score fue menor en el patrón axonal (medianas: 37.00 vs. 45.5, p = 0.024). No se presentaron diferencias en la afección sistémica entre patrones electrofisiológicos. CONCLUSIÓN: Es poco probable que los patrones electrofisiológicos tengan una correspondencia clínica extraneurológica clara, sin embargo, esto deberá probarse de forma definitiva con un mayor tamaño de muestra.

General and Abdominal Adiposity and Mortality in Mexico City: A Prospective Study of 150 000 Adults.

Background: Some reports suggest that body mass index (BMI) is not strongly associated with mortality in Hispanic populations. Objective: To assess the causal relevance of adiposity to mortality in Mexican adults, avoiding reverse causality biases. Design: Prospective study. Setting: 2 Mexico City districts. Participants: 159 755 adults aged 35 years and older at recruitment, followed for up to 14 years. Participants with a hemoglobin A1c level of 7% or greater, diabetes, or other chronic diseases were excluded. Measurements: BMI, waist-to-hip ratio, waist circumference, and cause-specific mortality. Cox regression, adjusted for confounders, yielded mortality hazard ratios (HRs) after at least 5 years of follow-up and before age 75 years. Results: Among 115 400 participants aged 35 to <75 years at recruitment, mean BMI was 28.0 kg/m2 (SD, 4.1 kg/m2) in men and 29.6 kg/m2 (SD, 5.1 kg/m2) in women. The association of BMI at recruitment with all-cause mortality was J-shaped, with the minimum at 25 to <27.5 kg/m2. Above 25 kg/m2, each 5-kg/m2 increase in BMI was associated with a 30% increase in all-cause mortality (HR, 1.30 [95% CI, 1.24 to 1.36]). This association was stronger at ages 40 to <60 years (HR, 1.40 [CI, 1.30 to 1.49]) than at ages 60 to <75 years (HR, 1.24 [CI, 1.17 to 1.31]) but was not materially affected by sex, smoking, or other confounders. The associations of mortality with BMI and waist-to-hip ratio were similarly strong, and each was weakened only slightly by adjustment for the other. Waist circumference was strongly related to mortality and remained so even after adjustment for BMI and hip circumference. Limitation: Analyses were limited to mortality. Conclusion: General, and particularly abdominal, adiposity were strongly associated with mortality in this Mexican population. Primary Funding Source: Mexican Health Ministry, Mexican National Council of Science and Technology, Wellcome Trust, Medical Research Council, and Kidney Research UK.

Evaluation of Cerebral Hemodynamics with Color-Coded Duplex Sonography: Normative Values with Correction of Insonation Angles.

BACKGROUND: Transcranial color-coded sonography (TCCS) allows direct observation of arteries and the possibility of correcting the insonation angle for reliable evaluation of hemodynamics. We obtained TCCS reference values of the cerebral hemodynamics after correction of insonation angles. METHODS: We studied 195 healthy adults equally allocated into 3 age groups: 18-40, 41-60, and greater than or equal to 61 years. The middle (MCA), anterior (ACA), and posterior cerebral arteries (PCA) were evaluated through the temporal acoustic window using conventional pulsed transcranial Doppler and TCCS. Peak systolic, end diastolic, and mean blood flow velocities were registered, as well as pulsatility and resistance indices at 0° and with correction by alignment of insonation angle parallel to the blood flow vector. We derived normative values assuming both the parametric and nonparametric distributions. RESULTS: We excluded 33 participants due to inadequate acoustic window (10.3%), carotid disease (2.1%), and embryonic variants (4.6%), leaving out 162 for final analysis (50% female, median age 48 years). The 2.5th-97.5th percentiles of the corrected angle for MCA was 0°-60°, ACA 0°-44°, and PCA 30°-60°. After angle correction, 2.5th-97.5th percentiles for flow velocity of MCA, ACA, and PCA were 37.7-112.5 cm/s, 25.6-71.2 cm/s, and 29.2-80.8 cm/s, respectively. There were wide discrepancies between hemodynamics values obtained with insonation angles at 0° and after angle correction. No differences were found between ultrasound methods at exactly 0° or between hemispheres, however, there were differences according to age and sex. CONCLUSIONS: Specific normative tables should be used in TCCS when the corrected angle is greater than 0° since the hemodynamics values greatly differ after correction of the insonation angle. Further studies are necessary to determine critical cutoffs indicating disease.

Reliability of Bystander Recognition of Clinical Features in Pre-Hospital Classification of Acute Cerebrovascular Syndromes: Preliminary Findings.

BACKGROUND: The recognition of stroke symptoms by patients or bystanders directly affects the outcomes of patients with acute cerebrovascular disease. OBJECTIVE: The objective of the study was to assess the predictive value of the medical his- tory and clinical features recognized by the patients' bystanders to classify neurovascular syndromes in pre-hospital settings. METHODS: We included 150 stroke patients of two Mexican referral centers: 50 with acute ischemic stroke (AIS), 50 with intracerebral hemorrhage (ICH), and 50 with subarachnoid hemorrhage (SAH). The performance of clinical prediction rules (CPR) to identify the stroke types was evaluated with features recognized by the patients' bystanders before hospital arrival. The impact of CPRs on early arrival and in-hospital mortality was also analyzed. RESULTS: Overall, 72% of the patients had previous medical evaluations in other centers before final referral to our hospitals, and therefore, only 45% had a final onset- to-door time <6 h, even when the first medical assessment had occurred in ≤1 h in 75% of cases. Clinical features noticed by the patients' bystanders had low positive predictive values (PPV) for any stroke type. The CPR "language or speech disor- der + focal motor deficit" had 93% sensitivity and a negative predictive value (NPV) of 84% to distinguish AIS. In SAH, head- ache alone showed a sensitivity of 84% and NPV of 97%. No CPR had an adequate performance on ICH. CPRs were not as- sociated with final onset-to-door time. Altered consciousness, age ≥65 years, indirect arrival with stops before final referral, and atrial fibrillation increased in-hospital mortality. CONCLUSION: Clinical features referred by the witness of a neurovascular emergency have limited PPV, but adequate NPV in ruling-out AIS and SAH among stroke types. The use of CPRs had no impact on onset-to-door time or in-hospital mortality when the final arrival to a third-level center occurs with previous medical refer- rals.

Toxoplasma infection in kidney donors and transplant recipients from Western Mexico: A one-year follow-up.

PURPOSE: Solid organ transplant recipients are highly susceptible to Toxoplasma gondii infection. We aimed to describe the 12-month follow-up risk of seroconversion in renal transplant recipients. METHODOLOGY: Anti-T gondii antibodies were investigated in donors and recipients of renal transplants. In donors, anti-T gondii were evaluated before transplantation. In recipients, anti-T gondii were monitored over a 12-month period to evaluate potential seroconversion or reactivation. IgG and IgM anti-T gondii antibodies were investigated through enzyme immunoassay and Western blot. Molecular diagnosis was performed on peripheral blood leukocytes using PCR to amplify fragments corresponding to the T gondii B1 gene and the repetitive 529-bp element. RESULTS: The basal frequency of seropositive IgG anti-T gondii antibodies was higher in donors than in recipients (38.4% vs 25.2%; P = .03). During the 12-month follow-up, the accumulated seroconversion to IgG and IgM antibodies was 3/99 (3.0%), and the accumulated reactivation was 11/99 (11.0%). None of the samples exhibited positivity to T gondii DNA. CONCLUSIONS: This study showed that there is an increased risk of seroconversion or reactivation in renal transplant recipients over a 12-month follow-up. Our data suggest that prophylaxis with trimethoprim and sulfamethoxazole effectively prevented toxoplasmosis, since neither T gondii DNA nor clinical toxoplasmosis was detected.

Hypertensive thalamic hemorrhage: analysis of short-term outcome.

BACKGROUND: Hypertension is the main cause of intracerebral hemorrhage with a thalamic location frequency that varies from 6% to 26.5%. OBJECTIVE: We aimed to identify clinical and radiological features that could impact the short-term prognosis in patients with hypertensive thalamic hemorrhage (HTH). METHODS: Consecutive patients presenting to a tertiary referral hospital with HTH were analyzed from 2010 to 2014. Clinical features at emergency department and a 30-day outcome using the modified Rankin Scale (mRS) were obtained. RESULTS: A total of 104 patients were studied (53 women, mean age 68.2 years, range 27-91 years), 91 (87.5%) of them with hypertension history. Mean hemorrhage volume was 12.2 mL (range 2-45 mL), without significant differences according to gender or age group. Irruption into the ventricular system occurred in 79 (76%) cases. Thirty-day mortality was 38.5% and occurred with a higher frequency in men, in patients with GCS <8, intraventricular irruption, ventriculostomy, and intracerebral hemorrhage volumes >15 mL. CONCLUSIONS: Although HTH is associated with relatively small hemorrhage volume, it had a higher frequency of ventricular irruption and bad prognosis at short-term.

Enfermedad carotídea aterosclerosa y enfermedad de sustancia blanca en sujetos sin historia de infarto cerebral o isquemia cerebral transitoria.

INTRODUCTION: Atherosclerotic carotid artery disease (CAD) is a major risk factor for cerebrovascular disease. OBJECTIVE: To analyze the association of major vascular risk factors with atherosclerotic CAD and white matter disease (WMD) in patients without a history of ischemic stroke. METHOD: Risk factors were assessed with carotid examination using Doppler duplex ultrasound. Cases with a history cerebral infarction or transient ischemic attack were not included. Subjects had brain magnetic resonance imaging scans available and those with large-artery ischemic lesions were excluded. Multivariate models were constructed for the prediction of atherosclerotic CAD, significant carotid stenosis, atheroma burden and WMD. RESULTS: One-hundred and forty-five subjects were assessed (60.7% were females, mean age was 73 years). Atherosclerotic CAD was documented in 54.5%, carotid stenosis ≥ 50% in 9.0%, > 6 atheroma plaques in 7.6%, and periventricular or subcortical WMD in 28.3% (20.6% had atherosclerotic CAD and WMD concurrently). Risk factors independently associated with atherosclerotic CAD were age and hypertension; hypertension was associated with ≥ 50% carotid stenosis; age was associated with > 6 atheroma plaques; and age, diabetes and hypertension were associated with WMD. Obesity was not associated with any of the analyzed independent variables. CONCLUSIONS: In asymptomatic subjects without a history of ischemic stroke, age and hypertension were the most important risk factors for macrovascular disease. Diabetes mellitus was associated with microvascular disease. Obesity alone was not a major determinant of CAD or WMD.

INTRODUCCIÓN: La enfermedad carotídea aterosclerosa (ECA) es un factor de riesgo importante para enfermedad vascular cerebral. OBJETIVO: Analizar la asociación entre factores de riesgo vascular mayores con ECA y leucopatía cerebral en pacientes sin historia de ictus isquémico. MÉTODO: Se evaluaron factores de riesgo en sujetos con exploración de carótidas mediante ultrasonografía Doppler dúplex. No se incluyeron casos con historia de infarto cerebral o ataque isquémico transitorio. Los sujetos contaron con resonancia magnética cerebral y se excluyeron aquellos con lesiones isquémicas de grandes vasos. Se construyeron modelos multivariable para la predicción de ECA, estenosis carotídea significativa, carga de ateromas y leucopatía cerebral. RESULTADOS: Se estudiaron 145 sujetos (60.7 % mujeres, edad de 73 años). Se documentó ECA en 54.5 %, estenosis carotídea ≥ 50 % en 9 %, carga de placas de ateroma > 6 en 7.6 % y leucopatía periventricular o subcortical en 28.3 % (20.6 % tenían concurrentemente ECA y leucopatía). Los factores asociados independientemente con ECA fueron edad e hipertensión; con estenosis ≥ 50 %, hipertensión; con cargas de ateromas > 6 placas, edad; con leucopatía, edad, diabetes e hipertensión. La obesidad no se asoció con las variables independientes analizadas. CONCLUSIONES: En los sujetos asintomáticos sin historia de ictus isquémico, la edad y la hipertensión fueron los factores de riesgo más importantes para enfermedad macrovascular. La diabetes mellitus se asoció con enfermedad microvascular. La obesidad por sí sola no fue un determinante mayor de ECA o leucopatía cerebral.