Background: The nutritional status at the time of stroke, may influence the functional capacity after the event. There are controversial data indicating that obesity may be related to better prognosis. It is possible that some obese individuals present reduced fat-free mass.
Objective: To identify if bedside evaluation of body composition by the body mass index (BMI), muscle mass measured by adductor pollicis muscle thickness (APMT), arm muscle area (AMA) and the combination of low APMT or AMA with obesity are associated with poor functional status and mortality, 90 days after stroke.
Methodology: Were evaluated 120 patients hospitalized at Stroke Unit. Data was expressed by average ± standard deviation or median and percentiles. Obesity was evaluated by BMI and fat-free mass was estimated by the APMT, which is the only directly measured muscle, and AMA. Roc curve and multivariate logistic regression analysis were used to measure whether the APMT and obesity were associated with RANKIN ≥3 (greater dependence and death), after 90 days of the event. The data were adjusted by the NIHSS, sex, age, type of stroke and thrombolysis. Significance level was 5%.
Results: Of 120 patients, 54 (45.0%) were women and 66 (55.0%) men; age 66.6 ± 13.2 years; 109 patients (90.8%) had ischemic stroke and 11 (9.16%) hemorrhagic; NIHSS 4 (2-10). Among patients with ischemic stroke, 18 (16.5%) were thrombolized. Considering RANKIN ≥3, Roc curve analysis showed that the value of the cutoff for APMT was <12.5 mm, with sensitivity 0.84, specificity 0.58, area under the curve 0.75 ( 0,6629 - 0,8440) (p = 0.<0,001). In multivariate analysis adjusted by the above factors, the increase in each 1 mm of APTM reduce 31% the chance of disability (OR 0.764, 95% CI: 0.613 to 0.951) (p = 0.016). In addition, the intersection of obesity with APMT<12,5 mm, increased in 37 folds the risk of disability. AMA was not associated with RANKIN≥3.
Conclusion: Lower APMT alone or in combination with obesity was associated with poor functional status. The body composition assessment was performed at bedside, in the setting of Stroke Unit, with simple methods that may be feasible and useful to predict Stroke prognosis.