Neurology February 2009 Volume 72 Issue 8

Background: It is unclear whether patients age 65 years and over with a recent stroke or TIA benefit from statin treatment to a similar degree as younger patients.Methods: The 4,731 patient cohort in the SPARCL study was divided into an elderly group (65 and over) and a younger group. The primary endpoint (fatal or nonfatal stroke) and secondary endpoints were analyzed, with calculation of the hazard ratio (HR) and p values from a Cox regression model.Results: There were 2,249 patients in the elderly group and 2,482 in the younger group. The baseline LDL (133 mg/dL) and total cholesterol were comparable in the two groups. The elderly and younger groups had a 61.4 mg/dL and 58.7 mg/dL decrease in mean LDL during the trial. The primary endpoint was reduced by 26% in younger patients (HR 0.74, 0.57-0.96, p = 0.02) and by 10% in elderly subjects (HR 0.90, 0.73-1.11, p = 0.33). A test of heterogeneity for a treatment-age interaction was not significant (p = 0.52). The risk of stroke or TIA (HR 0.79, p = 0.01), major coronary events (HR 0.68, p = 0.035), any coronary heart disease event (HR 0.61, p = 0.0006), and revascularization procedures (HR 0.55, p = 0.0005) was reduced in the elderly group.Conclusions: There was no heterogeneity in the stroke reduction seen with atorvastatin in the elderly and younger groups. Cardiac events and revascularization procedures were also lower in both the elderly and younger subgroups treated with atorvastatin. These results support the use of atorvastatin in elderly patients with recent stroke or TIA.GLOSSARY: CHD = coronary heart disease; LDL-C = low-density lipoprotein cholesterol; RRR = relative risk reduction; SPARCL = Stroke Prevention by Aggressive Reduction in Cholesterol Levels.(C)2009AAN Enterprises, Inc.

Background: With the recent emphasis on core competencies, medical schools and residency programs have attempted to monitor and regulate trainees' patient encounters. The educational validity of this practice is unknown. Our objective was to determine whether patient encounter logs correlate with educational outcomes.Methods: We reviewed patient logs of all 212 neurology clerkship students from the 2005-2006 academic year and determined the number of patients each student saw in five diagnostic categories (seizure, headache, stroke, acute mental status change, and dementia). We compared these numbers with the students' written examination scores (total and category-specific) and clinical evaluation scores using Pearson product-moment correlations.Results: The more patients in a given diagnostic category that students saw, the lower the students' examination subscores in that disease category (r = -0.066, p = 0.03). The total number of patients each student saw did not correlate with the student's total examination score (r = -0.021, p = 0.77) or the student's overall clinical performance rating (r = 0.089, p = 0.23).Conclusions: Higher numbers of logged patients did not correlate with better clerkship performance, whether the outcome measures were written tests or faculty ratings, and whether the analysis involved total or disease-specific patient counts. Thus, patient census may not be a meaningful index of educational experience or outcome. Considerable time, money, and effort are required to maintain accurate logs of trainees' encounters with patients; based on the current study, this may be an inefficient use of resources.GLOSSARY: IRB = Institutional Review Board; NBME = National Board of Medical Examiners; OSCE = Objective Structured Clinical Examination.(C)2009AAN Enterprises, Inc.

Background: Posterior reversible encephalopathy syndrome (PRES) is characterized by vasogenic subcortical edema without infarction. It has been associated with hypertensive crises and with immunosuppressive medications but not with neuromyelitis optica (NMO).Methods: We reviewed the clinical and neuroimaging features of five NMO-immunoglobulin G (IgG) seropositive white women who experienced an episode of PRES and had a coexisting NMO spectrum disorder (NMOSD). We also tested for the aquaporin-4 (AQP4) water channel autoantibody (NMO-IgG) in 14 patients from an independently ascertained cohort of individuals with PRES.Results: All five patients developed abrupt confusion and depressed consciousness consistent with PRES. The encephalopathy resolved completely within 7 days. Comorbid conditions or interventions recognized to be associated with PRES included orthostatic hypotension with supine hypertension, plasma exchange, IV immunoglobulin treatment, and high-dose IV methylprednisolone. Brain MRI studies revealed bilateral T2-weighted (T2W) hyperintense signal abnormalities, primarily in frontal, parieto-occipital, and cerebellar regions. Three patients had highly symmetric lesions and three had gadolinium-enhancing lesions. Follow-up neuroimaging revealed partial or complete disappearance of T2W hyperintensity or gadolinium-enhancing lesions in all five patients. Patients with PRES without NMOSD were uniformly NMO-IgG seronegative.Conclusions: Brain lesions in some patients with neuromyelitis optica spectrum disorder (NMOSD) may be accompanied by vasogenic edema and manifest as posterior reversible encephalopathy syndrome (PRES). Water flux impairment due to aquaporin-4 autoimmunity may predispose to PRES in patients with NMOSD who experience blood pressure fluctuations or who are treated with therapies that can cause rapid fluid shifts.GLOSSARY: ADC = apparent diffusion coefficient; AQP4 = aquaporin-4; DWI = diffusion-weighted imaging; FLAIR = fluid-attenuated inversion recovery; Gd = gadolinium; IgG = immunoglobulin G; IVIg = IV immunoglobulin; IVMP = IV methylprednisolone; LETM = longitudinally extensive transverse myelitis; NMO = neuromyelitis optica; NMOSD = neuromyelitis optica spectrum disorder; ON = optic neuritis; PLEX = plasma exchange; PRES = posterior reversible encephalopathy syndrome; T2W = T2-weighted.(C)2009AAN Enterprises, Inc.

Objective: To describe the temporal patterns of incidence and demographic characteristics of amyotrophic lateral sclerosis (ALS) in Piemonte and Valle d'Aosta, Italy, in the 10-year period 1995 through 2004.Methods: The Piemonte and Valle d'Aosta Register for ALS (PARALS) is a prospective register collecting all cases of ALS incident in two regions of northwestern Italy (population: 4,332,842) since 1995. The cases are identified using several concurrent sources. ALS diagnosis is based on El Escorial criteria.Results: During the 10-year period of observation, 1,347 residents in the study area were diagnosed with ALS. In 1,260 of these cases, a diagnosis of definite or probable ALS was made at presentation or during the follow-up. The mean annual crude incidence rate was 2.90/100,000 population (95% confidence interval [CI], 2.72 to 3.09). The crude prevalence rate (December 31, 2004) was 7.89 (95% CI, 7.09 to 8.75)/100,000 population. According to the capture-recapture estimation, 27 patients were unobserved, thus increasing the annual observed crude incidence to 2.96/100,000 population. The incidence rate did not show any relevant variation during the 10-year period of the study and was constantly higher among men. The demographics and clinical features did not change between the 1995-1999 and the 2000-2004 cohorts, with the notable exception of the mean time delay from onset to diagnosis, which was significantly decreased in the last 5-year period.Conclusions: In the examined decade, the incidence of amyotrophic lateral sclerosis in Italy has been stable, and the clinical and demographic characteristics of the patients have shown no relevant modifications.GLOSSARY: ALS = amyotrophic lateral sclerosis; CI = confidence interval; EEC = El Escorial diagnostic criteria; EEC-R = El Escorial revised criteria; MND = motor neuron disease; PARALS = Piemonte and Valle d'Aosta Register for ALS; PCRA = Piemonte Central Regional Archive; VACRA = Valle d'Aosta Central Regional Archive.(C)2009AAN Enterprises, Inc.

Objective: To investigate associations between vascular risk profile and cerebral glucose metabolism.Methods: Subjects ranged from normal to having dementia (age >55 years) and underwent neuropsychological testing, MRI, and FDG PET scanning (n = 58). The Framingham Cardiovascular Risk Profile (FCRP) and its individual components were used as covariates in regression analyses with each PET scan using SPM2.Results: Analyses revealed broad areas of the frontal lobe in which higher FCRP was associated with lower normalized glucose metabolism including the superior medial frontal, superior frontal and superior orbital frontal cortex and the ventrolateral prefrontal cortex. Significant associations were predominately found in the left hemisphere. Independent component analyses revealed interesting regions but further confirm the relevance of the integrative measure of coronary risk.Conclusions: Although the mechanism of this association bears further investigation, this finding provides further evidence that vascular risk factors have malignant effects on the brain, particularly in the prefrontal cortex.GLOSSARY: 2D = two-dimensional; AD = Alzheimer disease; CDR = Clinical Dementia Rating; CIND = cognitively impaired not demented; CVD = cerebrovascular disease; FCRP = Framingham Cardiovascular Risk Profile; FDG = fluorodeoxyglucose; FWHM = full-width, half-maximum; MDT2 = minimal deformation template; MMSE = Mini-Mental State Examination; MNI = Montreal Neurologic Institute; TE = echo time; TR = repetition time.(C)2009AAN Enterprises, Inc.

Background: There are many different white matter disorders, both inherited and acquired, and consequently the diagnostic process is difficult. Establishing a specific diagnosis is often delayed at great emotional and financial costs. The pattern of brain structures involved, as visualized by MRI, has proven to often have a high diagnostic specificity.Methods: We developed a comprehensive practical algorithm that relies mainly on the characteristics of brain MRI.Results: The initial decision point defines a hypomyelination pattern, in which the cerebral white matter is hyperintense (normal), isointense, or slightly hypointense relative to the cortex on T1-weighted images, vs other pathologies with more prominent hypointensity of the cerebral white matter on T1-weighted images. In all types of pathology, the affected white matter is hyperintense on T2-weighted images, but, as a rule, the T2 hyperintensity is less marked in hypomyelination than in other pathologies. Some hypomyelinating disorders are typically associated with peripheral nerve involvement, while others are not. Lesions in patients with pathologies other than hypomyelination can be either confluent or isolated and multifocal. Among the diseases with confluent lesions, the distribution of the abnormalities is of high diagnostic value. Additional MRI features, such as white matter rarefaction, the presence of cysts, contrast enhancement, and the presence of calcifications, further narrow the diagnostic possibilities.Conclusion: Application of a systematic decision tree in MRI of white matter disorders facilitates the diagnosis of specific etiologic entities.(C)2009AAN Enterprises, Inc.