Short-latency afferent inhibition during selective finger movement

During individual finger movement, two opposite phenomena occur at the level of the central nervous system that could affect other intrinsic hand muscle representations, unintentional co-activation, and surround inhibition (SI). At rest, excitability in the motor cortex (M1) is inhibited at about 20 ms after electric stimulation of a peripheral nerve [short-latency afferent inhibition (SAI)]. We sought to determine whether SAI changes during selective index finger movement. Effects were measured by the response to transcranial magnetic stimulation in two functionally distinct target muscles of the hand [abductor digiti minimi muscle (ADM), first dorsal interosseus muscle (FDI)]. An increase in SAI in the ADM during index finger movement compared to at rest could help explain the genesis of SI. Electrical stimulation was applied to either the little finger (homotopic for ADM, heterotopic for FDI) or the index finger (heterotopic for ADM, homotopic for FDI). During index finger movement, homotopic SAI was present only in the ADM, and the effect of peripheral stimulation was greater when there was less co-activation. Heterotopic SAI found at rest disappeared with movement. We conclude that during movement, homotopic SAI on the muscle in the surround of the intended movement may contribute to SI

Rising statin use and effect on ischemic stroke outcome

BACKGROUND: Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) have neuroprotective effects in experimental stroke models and are commonly prescribed in clinical practice. The aim of this study was to determine if patients taking statins before hospital admission for stroke had an improved clinical outcome. METHODS: This was an observational study of 436 patients admitted to the National Institutes of Health Suburban Hospital Stroke Program between July 2000 and December 2002. Self-reported risk factors for stroke were obtained on admission. Stroke severity was determined by the admission National Institutes of Health Stroke Scale score. Good outcome was defined as a Rankin score < 2 at discharge. Statistical analyses used univariate and multivariate logistic regression models. RESULTS: There were 436 patients with a final diagnosis of ischemic stroke; statin data were available for 433 of them. A total of 95/433 (22%) of patients were taking a statin when they were admitted, rising from 16% in 2000 to 26% in 2002. Fifty-one percent of patients taking statins had a good outcome compared to 38% of patients not taking statins (p = 0.03). After adjustment for confounding factors, statin pretreatment was associated with a 2.9 odds (95% CI: 1.2–6.7) of a good outcome at the time of hospital discharge. CONCLUSIONS: The proportion of patients taking statins when they are admitted with stroke is rising rapidly. Statin pretreatment was significantly associated with an improved functional outcome at discharge. This finding could support the early initiation of statin therapy after stroke

Risk factors for ischemic stroke: A prospective study in Rochester, Minnesota

A cohort of 1,804 residents of Rochester, Minnesota, who were at least 50 years old, free of stroke, and who underwent examination at the Mayo Clinic in 1960, was followed for 13 years. During this period, there were 110 first ischemic strokes and 616 deaths without stroke. The time of onset, if available, or the time of diagnosis of potential risk factors was determined for all patients during the study and was used to construct a proportional hazards model of time to occurrence of stroke with time‐dependent risk factors. The model included 8 risk factors (2 fixed and 6 time dependent). For these, the individual relative risk are: 1.6 for age (per 10 years), 2.0 for males, 4.0 for definite hypertension, 3.9 for transient ischemic attacks, 2.2 for hypertensive heart disease, 2.2 for coronary heart disease, 1.7 for congestive heart failure, and 1.7 for diabetes mellitus. Atrial fibrillation was not a significant risk factor using time dependent multivariate analysis. Copyrigh

Intracerebral Hemorrhage: External Validation and Extension of a Model for Prediction of 30‐day Survival

We Report Validation of a Previously Reported Logistic Regression Model for Predicting 30‐day Survival after Supratentorial Intracerebral Hemorrhage using Independent, Propectively Collected Data. the Original Model, using Initial Glasgow Coma Scale Score, Hemorrhage Size, and Pulse Pressure, Accounted for Mortality or Survival at 30 Days in 92% of Patients in the Pilot Stroke Data Bank with a Sensitivity of 0.84 and a Specificity of 0.96. for External Validation, the Model Was Used to Predict 30‐day Status for Each Patient in the Main Phase Stroke Data Bank for Whom Complete Risk Factor Information Was Available. overall, 90% of Patients\u27 Outcomes Were Correctly Predicted with a Sensitivity of 0.85 and a Specificity of 0.92. Two Factors Not Collected in the Pilot Stroke Data Bank, Hyperglycemia and Intraventricular Hemorrhage Extension, Were Assessed to Determine If They Provided Additional Predictive Information on 30‐day Mortality. Intraventricular Hemorrhage Extension Contributed Significant Predictive Information in a Logistic Regression, Whereas Hyperglycemia Did Not. the Resulting Four‐factor Model with an Interaction Term (Intraventricular Hemorrhage Extension and Glasgow Coma Scale Score) Correctly Classified the Survival Status of 94% of Patients at 30 Days. a More General Outcome, Death or Failure to Achieve a Good Activities O Daily Living Score by One Year, Was Analyzed with Respect to the Same Four Factors. the Resulting Model Correctly Classified 95% of the Patients in the Cohort. Copyright © 1991 American Neurological Associatio