Abnormal vascular, metabolic biomarkers linked to impaired cognitive status in epilepsy
Ageing individuals with chronic epilepsy show multiple irregularities in metabolic, inflammatory and vascular health that are associated with poorer cognitive function, a study has found.
Researchers examined 40 individuals with chronic localization-related epilepsy (mean age 54.6 years) and 152 controls (mean age 55.3 years). All participants underwent neuropsychological assessment and clinical examination.
In addition, blood samples were collected and analysed for quantification of vascular status (systolic and diastolic blood pressure, body mass index [BMI], total and high-density lipoprotein [HDL] cholesterol level, homocysteine), inflammatory markers (high sensitivity C-reactive protein [hs-CRP], interleukin-6 [IL-6]) and metabolic status (insulin resistance [Homeostatic Model Assessment of Insulin Resistance (HOMA-IR)], glucose).
Results revealed that all cognitive factor scores were significantly lower in the epilepsy group than in the control group (p<0.0001 for all). Compared with controls, individuals with epilepsy also exhibited abnormalities in BMI (p=0.049), hs-CRP (p=0.046), HOMA-IR (p=0.0040) and fasting glucose (p=0.03).
Correlation coefficients demonstrated significant relationships between: 1) higher HOMA-IR and poorer immediate memory and visuospatial ability (p=0.03 for both); 2) elevated hs-CRP and poorer visuospatial (p=0.035) and verbal ability (p=0.06); 3) elevated BMI and poorer speed/flexibility (p=0.04), visuospatial (p=0.001) and verbal ability (p=0.02); 4) lower HDL and poorer verbal learning/delayed memory (p=0.01), speed/flexibility (p=0.043) and working memory (p=0.008).
Researchers pointed out that the finding that several markers of vascular, inflammatory and metabolic health are abnormal and related to impaired cognitive status is especially important, as many of such biomarkers are modifiable in nature.
Greater attention to the said factors in clinical care, particularly their underlying aetiology including the potential contributions of antiepileptic drugs and their induction of the cytochrome P450 (CYP) enzyme system, as well as important health and lifestyle factors, may help improve both health status and cognition in epilepsy, researchers said.