Functional recovery in ischemic stroke
Functional outcome at three months was studied in 72 patients with ischemic stroke. The Canadian Neurological Scale was used to assess the severity of stroke at admission and functional outcome at 3 months was assessed using modified Rankin scale. The size and site of the infarct was noted from the initial CT. Risk factors like hypertension, diabetes, and serum cholesterol were analyzed. Initial neurological scoring at admission, and size and site of the infarct were significantly associated with functional recovery at 3 months.
Stroke is one of the leading causes of death and disability worldwide. Morbidity and mortality associated with stroke have immense social and financial impact. For cost-effective management it is essential to identify the factors which determine the outcome in patients with stroke. The aim of the study was to evaluate the clinical profile of patients with ischemic stroke and to study the factors that affect their functional recovery.
All the consecutive patients with ischemic stroke admitted to our Institute within 48 hours of onset were included in the study. Patients with transient ischemic attacks, past history of cerebrovascular episode, cardio-embolic strokes, hemorrhagic strokes, stroke-related infections of the central nervous system, and head injury were excluded from the study.
The initial neurological scoring was done using the Canadian Neurological Scale (CNS). Routine investigations like blood sugar; serum cholesterol, kidney function test and ECG were carried out in all the patients. CT scan was done in every patient to know the size and site of the infarct. Patients were followed up for a period of 3 months. Neurological recovery was assessed using modified Rankin scale. Patients were evaluated at the time of discharge and at the end of 3 months. The outcome was said to be good when the score was 1-3 and bad when the grade score was 4-6.
Statistical Analysis: The tests used to find the statistical significance were Fishers exact test and Chi-square test for categorical variables.
Seventy-four patients of ischemic stroke were studied. There were 40 males (56.7%) and 32 females (43.1%). The mean age was 71.3 and the maximum number of patients were in the seventh decade. Seventy-two patients (97.2%) had motor weakness on one side of the body, 40 patients had the weakness on the right side, while 32 patients had it on the left side. Ten patients had altered level of consciousness. Speech disturbances were present in 22 patients (29.7%). Twenty-three patients (32.4%) had homonymous heminopia. Five patients (6.7%) had gaze palsy. In patients with posterior circulation stroke, 2 patients had 3rd nerve palsy and 1 patient had 9th, 10th and 12th nerve palsies. Headache was present in 6 patients (8.0%), vomiting was present in 1 patient and 4 patients (5.4%) had seizures. Hemianesthesia was seen in 26 (35.1%) patients.
Hypertension was present in 32 patients (43.2%), while 16 patients (21.6%) had diabetes mellitus. Eight patients (10.8%) had hypercholesteremia, 20 patients (27.0%) were chronic smokers, and 10 patients (13.5%) were chronic alcoholics.
Twenty-two patients (29.7%) had mild neurological deficit, CNS score > 7. Moderate neurological deficit was present in 40 patients (54%) who had a CNS score between 5 and 6.5. Twelve patients (16.2%) had a severe neurological deficit, CNS score < 4.5.
Majority of the patients (94.5%) had carotid circulation stroke. All these patients had strokes related to middle cerebral artery infarction. Occlusion of the deep penetrating branch was seen in 38 patients (54.2%), 22 patients (31.4%) had involvement of the superficial branch and 10 patients (14.2%) had occlusion of the middle cerebral artery trunk and a mixed type of infarct. Three cases had occlusion of the posterior cerebral artery, 2 had infarct in the midbrain, 1 in the occipital cortex, while 1 patient had a cerebellar infarct.
Size of the infarct
In 38 patients (51.3%) the size of the infarct was < 3 cm, while in 36 patients (48.6%) the infarct was > 3 cm in size.
There were 6 deaths during the evaluation period and 6 patients were lost for follow-up assessment. Of the 62 patients available for evaluation, good functional outcome was observed in 58% patients at 3 months follow-up [Table - 1].
Gender had no effect on the outcome. Older patients did poorly. Patients with non-dominant stroke fared better. Patients with hypertension had a worse outcome than patients with diabetes and hypercholesteremia.
Correlation Between the Severity of the Neurological Deficit and Functional Recovery
Of the 22 patients with a CNS score > 7, 2 were lost for follow-up, of the remaining 20 patients, 18 (90%) had a good outcome [Table - 2]. Follow-up data was available in 38 of the 40 patients with CNS scores between 5-6.5. Of these, 18 patients (47.3 %) had a good outcome. Twelve cases had CNS scores < 4.5. Only 4 patients in this subgroup came for follow-up and all had a poor outcome (P < 0.0003) [Table - 2].
Correlation Between the Site of the Infarct and Functional Recovery
Of the 70 patients with carotid circulation stroke, 38 had deep and 22 had superficial infarct .Out of the 38 patients with deep infarct, 36 patients had a follow-up. Twenty-six patients (72.2%) had a good outcome while 10 patients (27.7%) had a poor outcome. Out of the 22 patients with superficial infarct, 20 patients came for follow-up. Of these, 7 patients (35%) had a good outcome and 13 patients (65%) had a poor outcome. Ten cases had mixed infarct. Of these, 3 patients came for follow-up and all had a poor outcome. Of the 4 patients with posterior circulation stroke, 3 patients came for follow-up and all (100%) had a good outcome (P = 0.004) [Table - 3].
Correlation Between the Size of the Infarct and Recovery
Out of 38 patients with infarct size of less than 3 cm, 34 patients came for follow-up. Twenty-six patients (76.41%) had a good outcome, and 8 patients (23.52%) had a poor outcome. Out of 36 patients with infarct size of more than 3 cm, 28 patients came for follow-up. Ten (35.5%) patients had a good outcome and 18 patients (64.25%) had a poor outcome (P < 0.05) [Table - 4].
The neurological recovery after an ischemic stroke depends on many patient and disease-related variables and also on acute therapeutic interventions and rehabilitative measures. Significant neurological recovery occurs in the initial three to four weeks after the stroke. Eighty per cent patients reached their best activities of daily living within the first six weeks of stroke. In our study functional outcome was studied by modified Rankin's scale. This subjective scoring of recovery, in our opinion, was more suitable to the Indian settings than the more elaborate objective Barthel scoring system.
In our study the presence of hypertension was significantly associated with poor outcome. Similar results were obtained by Fiorelli et al. The presence of diabetes and hypercholisteremia was not significantly associated with poor recovery. A significant correlation of outcome was seen with the initial neurological scoring.4 There was no significant difference in the functional outcome between the internal carotid artery territory infarcts and the posterior cerebral artery territory infarcts. Joan, however, found a significantly better prognosis in posterior circulation strokes. When the outcome was compared in patients with deep or superficial and mixed infarct, it was better in deep hemispheric infarcts and patients with larger infarcts had a poorer outcome.,