['Alterations in blood fatty acid (FA) composition are associated with cardiovascular diseases. We investigated whether plasma FA composition was related to stroke severity and functional outcome in acute ischemic stroke patients.', 'We prospectively enrolled 156 patients with first-episode cerebral infarction, within 7 days of symptom onset. The proportion of FAs was analyzed using gas chromatography, and the summation of the omega-3 polyunsaturated fatty acids (ω3-PUFA), 18:3 ω3 α-linolenic acid, 20:3 ω3 eicosatrienoic acid, 20:5 ω3 eicosapentaenoic acid (EPA), and 22:6 ω3 docosahexaenoic acid (DHA) was reported as Σω3-PUFAs. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score on admission. Poor functional outcome was defined by modified Rankin scale (mRS) ≥3 at three months after the index stroke.', 'Lower proportions of EPA (β=-0.751), DHA (β=-0.610), and Σω3-PUFAs (β=-0.462) were independently associated with higher NIHSS score, after adjusting for stroke subtype, hemoglobin, high density lipoprotein, high sensitivity C-reactive protein, fasting glucose, 16:0 palmitic acid, and Σsaturated fatty acids. Moreover, a lower proportion of DHA (odds ratio [OR]: 0.20, 95% confidence interval [CI]: 0.04-0.88), and Σω3-PUFAs (OR: 0.22, 95% CI: 0.05-0.84) showed an independent relationship with poor functional outcome after adjusting for age, sex, smoking status, NIHSS score, stroke subtype, and 16:0 palmitic acid.'] Does low Plasma Proportion of Omega 3-Polyunsaturated Fatty Acids predict Poor Outcome in Acute Non-Cardiogenic Ischemic Stroke Patients?