How Comorbidity Reflects on Cerebrospinal Fluid Biomarkers of Neurodegeneration in Aging

Systemic comorbidity precipitates the risk for dementia. To comprehend the underlying mechanisms into a therapeutic perspective, we analyzed how comorbidity affects neurodegeneration-related cerebrospinal fluid (CSF) biomarkers of 55 cognitively intact subjects. The Charson Comorbidity Index (CCI) was correlated with CSF amyloid-β₄₂ (Aβ₄₂), amyloid-β₄₀, total-tau, 181-phosphorylated-tau (p-tau), the Aβ₄₂/p-tau ratio, neurogranin, and lactate. The age-related brain lesions at imaging were also considered. CCI had a raw association with Aβ₄₂/p-tau and p-tau, and a stronger, age-independent correlation with lactate. These preliminary findings suggested that, in normal subjects, systemic comorbidity might increase CNS oxidative stress and, together with aging, contribute to develop an Alzheimer's disease-like biochemical profile.