One-Year Prognosis and Outcome according to Age with Lateral Medullary Infarction

Abstract

Introduction: Few studies have compared stroke mechanisms and prognosis in lateral medullary infarction (LMI) between young and old patients. Here, I investigated the differences in the risk factors, etiologies, and prognosis between young and old patients with LMI. Materials and Methods: I reviewed retrospectively consecutive patients with acute LMI who were admitted within 7 days after symptom onset between February 2004 and January 2011. Neurological outcomes I measured by Barthel Index (BI) and Modified Rankin Scale (mRS) at 1 year, and clinical events were checked for 1 year. Patients were divided into two groups according to their age: 18-59 years (young age group), and over 60 years (old age group). I also divided the patients into two groups with favorable outcome (mRS score 0-1 and BI 95-100) and unfavorable outcome (mRS score ≥2 and BI <95). I performed Brain MR angiography (MRA) or conventional angiography to evaluate vascular pathologies. Results: A total of 106 patients were included in the study, of whom 37 were considered young patients (age, 18–59 years) and 69 were considered old patients (age, 60≥ years). The most common etiologic mechanism observed in this study was large artery atherosclerosis, which was observed in both groups (young group, 45.9%

old group, 75.4%). Arterial dissection and small vessel occlusion were common in the young age group (29.7% versus 2.9% in dissection

24.3% versus 8.7% in small vessel occlusion). Pneumonia was significantly high in the unfavorable outcome (mRS ≥2) group (p = 0.009). Multivariable logistic regression identified age (OR = 1.06

95% CI = 1.01–1.12) as a significant predictor of unfavorable outcome (mRS ≤ 1) at 1 year. Conclusions: This retrospective study suggests that LMI at a young age shows a good clinical outcome. Age is a significant prognostic factor for good functional outcome after LMI, regardless of other demographical or clinical characteristics. Arterial dissection and SVO are frequent stroke mechanisms in the young age patients. Thus, young patients with LMI require a detailed diagnostic work up to examine such stroke mechanisms.