SOD1 and diabetes mellitus: To evaluate the association between plasma EC-SOD concentration and comorbidity in SOD3 p.R231G variant non-carriers, we compared medical history including CKD, diabetes, stroke, CHD, and pneumonia among the top and bottom half groups of the EC-SOD concentration in SOD3 p.R231G variant non-carriers of the entire cohort, Very Old, and Centenarians (Fig. 4).