Relationship between Barthel Index (BI) and the Modified Rankin Scale (mRS) Score in Assessing Functional Outcome in Acute Ischemic Stroke

Abstract

Introduction: A more than one third of stroke survivors are left with permanent disability in the form of significant residualphysical, cognitive andpsychological impairments. The increasing emergences of new therapies for acute stroke suggest that there will be an increase in number of survivor living with disabilities. Accurate outcome prediction following stroke is important for the proper delivery ofpost stroke care and establishment of an effective continuing care program. Numerous trials have been undertaken to study the prognosis of stroke. Recent literature suggests the early clinical courses of the neurological deficit after acute stroke is dependent on the initial stroke severity. Methodology: Study was conducted at a tertiary care centre in over a period of 2 years. The diagnosis of stroke due to vascular event was confirmed in each case by neuroimaging (plain CT Scan Head/ MRIBrain) apart from the clinical evaluation. Patients screened were evaluated at enrolment (within 7 days from stroke onset) and during follow up at 04 weeks and 12 weeks after stroke by the same observer employing the same criteria used at the time of presentation using following scales: Barthel's index (BI) and modified Rankin Scale (mRS) score. All the patients were given standard care as per the guidelines of American Stroke Association. Primary outcome was to study the co-relation between BI and mRS in assessing functional outcome in acute ischemic stroke at the end of 4 weeks and 12 weeks and secondary outcome was to study the correlation between the functional outcome scales andfindings on neuroimaging of brain. Results: Sixty nine patients were screened for the study and 58 patients met the eligibility criteria. Out of 58 patients, 8 patients hadpresented within window period (3h - 41/2 h). The overall mortality during 12 weeks amounted to 10.3% and was higher in men (6.9%) than women (3.4%). Thefunctional outcome scores were calculated by using the BI and mRS at admission and follow up. The mean BI score at admission and at 12 weeks was 36.72 ± 23.72 and 63.88 ± 29.85 respectively. The mean mRS score at admission and at 12 weeks was 4.09 ± 0.77 and 3.00 ± 1.40 respectively. Correlation between the BI score and mRS score at admission, and during follow up showed a significant negative correlation (p<0.001). Infarct size and BI score at admission, 4 weeks and at 12 weeks were found to be negatively correlated (p<0.001) which means that as the infarct size increased, BI score decreased Infarct size and mRS score at admission, 4 weeks and at 12 weeks werefound to be positively correlated (p<0.001) which means that as the infarct size increased, mRS increased. Conclusion: Our study has demonstrated that stroke functional outcome can be predicted from the baseline BI and mRS scales. It is concluded thatBI and mRS Stroke scale can be used to prognosticate functional outcome at admission and at follow up.