SOD1 and Cognitive impairment: These data suggest that plasma SOD levels are not increased in these patients with cognitive impairment; rather, the decline in SOD levels indicates a deficit in antioxidant defense mechanisms in those CSVD subjects with cognitive impairment, since these CSVD patients are unable to remove the circulating superoxide anion, therefore suffering an increase in small vascular damage induced by ROS and neuroinflammation.