Aphasia in Stroke - Pattern and Prognosis: A Prospective study

INTRODUCTION: Stroke by definition is a syndrome of rapidly developing clinical signs of focal (or global) disturbance of cerebral function, lasting for more than 24 hours or leading to death, with no apparent cause other than vascular origin. Stroke is the leading cause of disability and death all around the world. In India, community surveys have shown a crude prevalence rate of “hemiplegia” in the range of 200 per 100,000 persons, constituting nearly 1.5% of all hospital admissions, 4.5% of all medical and 20% of all neurological admissions. The vascular pathologic processes that lead to stroke may be thrombosis, embolism, dissection or rupture of the vessel. These in turn can lead to two types of parenchymal changes in the brain- ischaemia with or without infarction or a haemorrhage. Atheroscelerotic vascular disease is the most common cause for stroke all round the world, but other causes like arteritis (due to tuberculosis etc) and cardioembolic stroke contribute significantly especially in India. The most important risk factors for stroke are hypertension, heart disease, atrial fibrillation, diabetes mellitus, cigarette smoking and hyperlipidemia. AIM OF STUDY: The aim of this study is to evaluate aphasia characteristics at the time of presentation in patients with acute stroke and evaluate the changes in language function after 6 months. 1. To study the types of aphasia and the differences in age, sex characteristics of patients with different types of aphasia in acute stroke patients (within 2 weeks) admitted in Government General Hospital, Chennai. 2. To study the pattern of recovery of aphasia in patients after 6 months of initial presentation and to determine the factors which affect the prognosis of the aphasia due to stroke. MATERIALS AND METHODS: This study enrolled patients admitted with acute stroke in the Institute of Internal Medicine of Government General Hospital, Chennai during the period from July 2003 to January 2005. Inclusion Criteria: · Duration of stroke less than 2 weeks, · Single stroke (either ischemic or hemorrhagic), · Confirmation by CT or MRI. Exclusion Criteria: · Multiple or bilateral stroke, · History of prior stroke, · Head trauma, · Delirium or Dementia, · Previous psychiatric illness, · Other causes of focal neurological deficits like tumour, infection, inflammation. · Significant hearing or visual impairment. CONCLUSIONS: Global aphasia is the most common aphasic syndrome in acute stroke patients, followed by Wernicke’s aphasia, Broca’s aphasia, Anomic aphasia, and Transmotor cortical aphasia. Age and Sex did not differ significantly across the various types of aphasia. · Recovery in patients with aphasia due to stroke is a dynamic process with evolution of aphasia from one type to another. There was some improvement in language function as reflected by the Aphasia Quotient in all patients followed up. The type of aphasia changed to a less severe form in 33% of patients. Nonfluent aphasia may evolve into fluent aphasia. Global aphasia evolved into either Wernicke or Broca’s aphasia. Broca’s and Transmotorcortical aphasia evolved into an Anomic aphasia. Anomic aphasia evolved to normal language function. There was no change in aphasia type in patients with Wernicke’s aphasia. · Age did not affect the recovery from aphasia. Recovery was better in women whose aphasia evolved more frequently to a less severe form. · The extent of recovery was inversely related to the initial severity of stoke as measured by the NIH stroke scale. · The maximum recovery in language function occurred in the first three months following the stroke.