Carlos Cantú-Brito

Serum Uric Acid and Outcome after Acute Ischemic Stroke: PREMIER Study

Background: Current evidence shows that uric acid is a potent antioxidant whose serum concentration increases rapidly after acute ischemic stroke (AIS). Nevertheless, the re-lationship between serum uric acid (SUA) levels and AIS outcome remains debatable. We aimed to describe the prognostic significance of SUA in AIS. Methods: We studied 463 patients (52% men, mean age 68 years, 13% with glomerular filtration rate <60 ml/min at hospital arrival) with AIS pertaining to the multicenter registry PREMIER, who had SUA measurements at hospital presentation. Multivariate models were constructed to analyze the association of SUA with functional outcome as assessed by the modified Rankin scale (mRS) at 30-day, 3-, 6- and 12-month follow-up. A mRS 0-1 was regarded as a very good outcome. Results: Mean SUA concentration at hospital arrival was 6.1 ± 3.7 mg/dl (362.8 ± 220.0 μmol/l). Compared with cases with higher SUA levels at hospital admission, patients with ≤4.5 mg/dl (≤267.7 μmol/l; the lowest tertile of the sample) had more cases of a very good 30-day outcome (30.5 vs. 18.9%, respectively; p = 0.004). SUA was not associated with mortality or functional dependence (mRS >2) at 30 days, or with any outcome measure at 3, 6 or 12 months poststroke. After adjustment for age, gender, stroke type and severity (NIHSS <9), time since event onset, serum creatinine, hypertension, diabetes and smoking, a SUA ≤4.5 mg/dl (≤267.7 μmol/l) was positively associated with a very good short-term outcome (odds ratio: 1.76, 95% confidence interval: 1.05-2.95; negative predictive value: 81.1%), but not at 3, 6 or 12 months of follow-up. When NIHSS was entered in the multivariate model as a continuous variable, the independent association of SUA with outcome was lost. Compared with cases with higher levels, patients with SUA ≤4.5 mg/dl (≤267.7 μmol/l) were more frequently younger than 55 years, women, with mild strokes, with normal serum creatinine and fewer had hypertension. The time since event onset to hospital arrival was not significantly associated with AIS severity or SUA levels; nevertheless, a nonsignificant tendency was observed for patients with severe strokes and high SUA levels arriving in <24 h. Conclusions: A low SUA concentration is modestly associated with a very good short-term outcome. Our findings support the hypothesis that SUA is more a marker of the magnitude of the cerebral infarction than an independent predictor of stroke outcome.

Cerebral venous thrombosis in a Mexican multicenter registry of acute cerebrovascular disease: the RENAMEVASC study.

BACKGROUND Cerebral venous thrombosis (CVT) is a rare form of cerebrovascular disease that is usually not mentioned in multicenter registries on all-type acute stroke. We aimed to describe the experience on hospitalized patients with CVT in a Mexican multicenter registry on acute cerebrovascular disease. METHODS CVT patients were selected from the RENAMEVASC registry, which was conducted between 2002 and 2004 in 25 Mexican hospitals. Risk factors, neuroimaging, and 30-day outcome as assessed by the modified Rankin scale (mRS) were analyzed. RESULTS Among 2000 all-type acute stroke patients, 59 (3%; 95% CI, 2.3-3.8%) had CVT (50 women; female:male ratio, 5:1; median age, 31 years). Puerperium (42%), contraceptive use (18%), and pregnancy (12%) were the main risk factors in women. In 67% of men, CVT was registered as idiopathic, but thrombophilia assessment was suboptimal. Longitudinal superior sinus was the most frequent thrombosis location (78%). Extensive (>5 cm) venous infarction occurred in 36% of patients. Only 81% of patients received anticoagulation since the acute phase, and 3% needed decompressive craniectomy. Mechanical ventilation (13.6%), pneumonia (10.2%) and systemic thromboembolism (8.5%) were the main in-hospital complications. The 30-day case fatality rate was 3% (2 patients; 95% CI, 0.23-12.2%). In a Cox proportional hazards model, only age <40 years was associated with a mRS score of 0 to 2 (functional independence; rate ratio, 3.46; 95% CI, 1.34-8.92). CONCLUSIONS The relative frequency of CVT and the associated in-hospital complications were higher than in other registries. Thrombophilia assessment and acute treatment was suboptimal. Young age is the main determinant of a good short-term outcome.

Door-to-Door Capture of Incident and Prevalent Stroke Cases in Durango, Mexico: The Brain Attack Surveillance in Durango Study

Background and Purpose— Stroke incidence and prevalence estimates in developing countries should include stroke cases not presenting to hospital. We performed door-to-door stroke case ascertainment in Durango Municipality, Mexico, to estimate stroke incidence and prevalence and to determine the error made by only ascertaining hospital cases. Methods— Between September 2008 and March 2009, 1996 housing units were randomly sampled to screen for stroke in Durango Municipality residents 35 years of age and older. Field workers utilized a validated screening tool. Those screening positive were referred to a neurologist for history and examination and a head CT scan. Prevalence and cumulative incidence from the door-to-door surveillance were calculated and compared with previously reported hospitalization rates during the same defined time. Results— Respondents included 2437 subjects from 1419 homes. The refusal rate was 3.8%. Twenty subjects had verified or probable stroke. The prevalence of probable or verified stroke was 7.7 per 1000 (95% CI, 4.3 per 1000–11.2 per 1000). Five patients had a stroke during the time of the hospital surveillance, yielding a cumulative incidence of 232.3 per 100 000 (95% CI, 27.8–436.9). Two of the 5 cases were captured by door-to-door surveillance but not by hospital surveillance. Conclusions— This study provides the first community-based stroke prevalence and incidence estimates in Mexico. The wide confidence intervals, despite the large number of surveyed housing units, suggest the need for more advanced sampling strategies for stroke surveillance in the developing world.

Hospitalized Stroke Surveillance in the Community of Durango, Mexico. The Brain Attack Surveillance in Durango Study

Background and Purpose— Vascular conditions are becoming the greatest cause of morbidity and mortality in developing countries. Few studies exist in Latin America. We aimed to perform a rigorous stroke surveillance study in Durango, Mexico. Methods— Active and passive surveillance were used to identify all patients with potential stroke presenting to Durango Municipality hospitals from August 2007 to July 2008. Exclusion criteria were subjects younger than 25 years old, stroke attributable to head trauma, and non-Durango Municipality residents. Brain Attack Surveillance in Durango-trained neurologists validated cases as stroke using source documentation. Stroke hospitalization rates were defined to include patients examined in the emergency department or admitted to the hospital. Results— Abstractors identified 435 potential cases; 309 (71%) were validated as stroke. Of the validated stroke cases, the median age was 71 and 49% were female. Subtypes were 61.5% ischemic stroke, 20.7% intracerebral hemorrhage, 7.4% subarachnoid hemorrhage, and 10.4% undetermined. Overall initial NIHSS was a median of 11 (interquartile range, 7–17); in-hospital mortality was 39%. When adjusted to the world population, the age-adjusted hospitalization rate of first-ever stroke was 118.2 per 100 000; rates by type were: ischemic stroke, 69.1 (95% CI, 57.5–80.7); intracerebral hemorrhage, 26.7 (95% CI, 19.6–33.8); subarachnoid hemorrhage, 9.5 (95% CI, 5.3–13.8); and unknown, 12.3 (95% CI, 7.4–17.3). Of 190 patients with validated ischemic stroke, 44.2% received lipid testing and 7.4% received carotid imaging and echocardiography; 1.1% received tissue plasminogen activator. Conclusion— To our knowledge, this is the first estimate of stroke hospitalization rates in a Mexican community and it provides information important for design of interventions to prevent and treat stroke. This information is critical to reduce Mexicos stroke burden.

Autoantibodies Against the Fibrinolytic Receptor, Annexin A2, in Cerebral Venous Thrombosis

Background and Purpose— Cerebral venous thrombosis (CVT) may be a manifestation of underlying autoimmune disease. Antibodies against annexin A2 (anti-A2Ab) coincide with antiphospholipid syndrome, in which antiphospholipid antibodies (aPLA) are associated with thrombosis in any vascular bed. Annexin A2, a profibrinolytic receptor and binding site for &bgr;2-glycoprotein-I, the main target for aPLA, is highly expressed on cerebral endothelium. Here we evaluate the prevalence of anti-A2Ab in CVT. Methods— Forty individuals with objectively documented CVT (33 women and 7 men) and 145 healthy controls were prospectively studied for hereditary and acquired prothrombotic risk factors, classical aPLA, and anti-A2Ab. Results— One or more prothrombotic risk factors were found in 85% of CVT subjects, (pregnancy/puerperium in 57.5%, classical aPLA in 22.5%, and hereditary procoagulant risk factors in 17.5%). Anti-A2Ab (titer >3 SD) were significantly more prevalent in patients with CVT (12.5%) than in healthy individuals (2.1%, P<0.01, OR, 5.9). Conclusions— Anti-A2Ab are significantly associated with CVT and may define a subset of individuals with immune-mediated cerebral thrombosis.

The first Mexican multicenter register on ischaemic stroke (the PREMIER study): demographics, risk factors and outcome.

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Cyclophosphamide treatment for unrelenting CNS vasculitis secondary to tuberculous meningitis

CNS arteritis develops in 30%–70% of TB meningitis cases.1,2 It often affects the basal arteries, resulting in ischemia and infarction of the diencephalon. In addition to anti-TB agents, treatment with steroids is used to modulate the inflammatory response. However, a paradoxical deterioration may follow.3,–,5 The most likely explanation is an enhanced delayed-type hypersensitivity response, leading to activation and accumulation of lymphocytes and macrophages at the site of bacillary deposition, or toxin production when the bacilli die.5 As with other types of vasculitis, steroids may not control such immunologic responses. ### Case report. A 19-year-old woman presented to the emergency department with fever, headache, ataxia, and altered mental status, with tachycardia and a temperature of 39°C. The neurologic examination showed papilledema, bilateral sixth nerve palsy, and nuchal rigidity. A chest X-ray revealed bilateral reticular infiltrates. The MRI showed meningeal enhancement, without parenchymal lesions (figure, A). The CSF examination revealed proteins of 189 mg/dL, glucose of 14 mg/dL, leukocytes of 47 cells/mm3, and adenosine deaminase enzyme of 10 …

Atherothrombotic Disease, Traditional Risk Factors, and 4-Year Mortality in a Latin American Population: The REACH Registry

Atherothrombosis is becoming the leading cause of chronic morbidity in developing countries. This epidemiological transition will represent an unbearable socioeconomic burden in the near future. We investigated factors associated with 4‐year all‐cause mortality in a Latin American population at high risk.

Central Adiposity and Mortality after First-Ever Acute Ischemic Stroke

Background: The waist-to-height ratio (WHtR) may be a better adiposity measure than the body mass index (BMI). We evaluated the prognostic performance of WHtR in patients with acute ischemic stroke (AIS). Methods: First, we compared WHtR and BMI as adiposity measures in 712 healthy adults by tetrapolar bioimpedance analysis. Thereafter, baseline WHtR was analyzed as predictor of 12-month all-cause mortality in 821 Mexican mestizo adults with first-ever AIS by a Cox proportional hazards model adjusted for baseline predictors. Results: In healthy individuals, WHtR correlated higher than BMI with total fat mass and showed a higher accuracy in identifying a high percentage of body fat (p < 0.01). In AIS patients a U-shaped relationship was observed between baseline WHtR and mortality (fatality rate 29.1%). On multivariate analysis, baseline WHtR ≤0.300 or >0.800 independently predicted 12-month all-cause mortality (hazard ratio 1.91, 95% confidence interval 1.04-3.51). BMI was not associated with mortality, tested either as continuous, binomial or stratified variable. Conclusion: WHtR is a modifiable risk factor that accurately demonstrates body fat excess. Extreme WHtR values were associated with increased 12-month all-cause mortality in Mexican mestizo patients with AIS. No survival advantage was found with high WHtR as the pragmatic indicator of obesity in this population.

Restless Legs Syndrome and Hypertension in Mexican Women

RLS is a common chronic disorder characterized by an irresistible need to move the lower limbs that affects sleep. Poor sleep has been associated with increased blood pressure (BP). Thus, we evaluated the cross‐sectional relationship between RLS and hypertension (HTN) in a large cohort study in Mexico.