Dysphagia May Be an Independent Marker of Poor Outcome in Acute Lateral Medullary Infarction

BACKGROUND AND PURPOSE The functional recovery after the lateral medullary infarction (LMI) is usually good. Little is known about the prognostic factors associated with poor outcome following acute LMI. The aim of this study was to identify the factors associated with poor long-term outcome after acute LMI, based on experiences at a single center over 11 years. METHODS A consecutive series of 157 patients with acute LMI who were admitted within 7 days after symptom onset was evaluated retrospectively. Clinical symptoms were assessed within 1 day after admission, and outcomes were evaluated over a 1-year period after the initial event. The lesions were classified into three vertical types (rostral, middle, and caudal), and the patients were divided into two groups according to the outcome at 1 year: favorable [modified Rankin Scale (mRS) score ≤1] and unfavorable (mRS score ≥2). RESULTS Of the 157 patients, 93 (59.2%) had a favorable outcome. Older age, hypertension, dysphagia, requirement for intensive care, and pneumonia were significantly more prevalent in the unfavorable outcome group. The frequencies of intensive care (13%) and mortality (16.7%) were significantly higher in the rostral lesion (p=0.002 and p=0.002). Conditional logistic regression analysis revealed that older age and initial dysphagia were independently related to an unfavorable outcome at 1 year [odds ratio (OR)=1.04, 95% confidence interval (95% CI)=1.001-1.087, p=0.049; OR=2.46, 95% CI=1.04-5.84, p=0.041]. CONCLUSIONS These results suggest that older age and initial dysphagia in the acute phase are independent risk factors for poor long-term prognosis after acute LMI.