The Paradoxical Protective Effect of Liver Steatosis on Severity and Functional Outcome of Ischemic Stroke

This makes no sense. Go back and figure this out based on objective damage reports(size and location). NIHSS has no objectivity at all. 

The Paradoxical Protective Effect of Liver Steatosis on Severity and Functional Outcome of Ischemic Stroke

Minyoul Baik¹, Seung Up Kim^2,3, Hyo Suk Nam¹, Ji Hoe Heo¹ and Young Dae Kim^1*

• ¹Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
• ²Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, South Korea
• ³Yonsei Liver Center, Severance Hospital, Seoul, South Korea

Background: There is very limited information on the relationship between non-alcoholic fatty liver disease (NAFLD) and the severity or functional outcomes of ischemic stroke or transient ischemic stroke (TIA). We investigated the correlation between NAFLD and stroke outcomes.

Methods: NAFLD was assessed in 321 patients with first-ever acute ischemic stroke or TIA, who underwent transient elastography from January 2014 to December 2014. The association of liver steatosis with stroke severity, assessed using the National Institute of Health Stroke Scale (NIHSS), was investigated using robust regression analysis. We also compared the functional outcome at 90 days according to the presence or burden of liver steatosis.

Results: NAFLD was observed in 206 (64.2%) patients. Patients with NAFLD had less severe stroke (median NIHSS score 2 vs. 3, P = 0.012) and more favorable functional outcome at 90 days (85.3 vs. 70.5, P = 0.004). Patients with NAFLD were likely to have a 23.3% lower [95% confidence interval (CI), −39.2 to −3.2%, P = 0.026] NIHSS score and a 2.5-fold higher (95% CI, 1.08–5.67, P = 0.033) possibility of favorable functional outcome in multivariate analysis.

Conclusions: Our study shows that a higher burden of liver steatosis seems to be associated with less severe stroke and better functional outcome after ischemic stroke or TIA.

Introduction

Non-alcoholic fatty liver disease (NAFLD) is a spectrum of diseases from simple steatosis to steatohepatitis with varying degree of fibrosis, and liver cirrhosis (1, 2). NAFLD is becoming the most common chronic liver disease worldwide including Korea, affecting approximately 25% of the general population (3, 4). NAFLD is closely associated with obesity, insulin resistance, and type 2 diabetes mellitus, and is even recognized as a manifestation of metabolic syndrome in the liver (5). Furthermore, NAFLD is known to be clearly associated with cardiovascular morbidity and mortality (6, 7), and liver fibrosis is especially considered the key determinant (7–11).

Ischemic stroke is also suggested to be associated with NAFLD, especially liver fibrosis (7, 10, 12). In the previous study, we found that there was 41.5% of patients with NAFLD in ischemic stroke patients (10), similar with previous reports (23.0–42.7%) from other countries (12–14). However, there is a paucity of studies attempting to find the association between NAFLD and the stroke severity or functional outcome after ischemic stroke (12, 14, 15). Some previous studies, which defined NAFLD as the presence of elevated aminotransferase levels without apparent causes (12, 14, 15), failed to show a statistically significant association between NAFLD and stroke outcomes (12, 15).

Therefore, we sought to assess the association between NAFLD and the severity or functional outcome in patents with ischemic stroke. In this study, the presence of NAFLD was based on transient elastography (TE), which is known to be a well-qualified method for the diagnosis of NAFLD and could separately evaluate the degree of liver steatosis and stiffness (16, 17).