Nucleus basalis of Meynert damage and cognition in patients with multiple sclerosis

Background The nucleus basalis of Meynert (NBM), representing the major source of cerebral cholinergic innervations, is vulnerable to neurodegeneration in Alzheimer's and Parkinson's disease. Objective To determine associations between NBM properties and cognitive outcomes in patients with multiple sclerosis (PwMS). Methods 84 PwMS and 19 controls underwent 3T MRI, the Paced Auditory Serial Addition Test (PASAT) and subtests of the Brief International Cognitive Assessment for MS (BICAMS). NBM volume, fractional anisotropy, mean diffusivity (MD), axial diffusivity and radial diffusivity (D-perpendicular to) were calculated. Analyses assessed relationships between cognition and NBM measures. Linear regressions evaluated the prognostic value of baseline measures in predicting cognitive change over 3 years of follow-up (n = 67). Results Cognitive tests correlated with NBM diffusivity in PwMS (range r = - 0.29 to r = - 0.40, p < 0.05). After accounting for NBM volume, NBM MD and D-perpendicular to explained additional variance (adjusted R-2 range 0.08-0.20, p < 0.05). Correlations between NBM imaging metrics and cognitive tests remained significant when including imaging parameters of other cognitive key brain regions in the models. After controlling for age, education, and baseline cognitive test score, NBM measures predicted change in cognition over follow-up in 5 of 10 and 2 of 10 assessments in the relapsing-remitting sample (n = 43) (adjusted R-2 range from 0.23 to 0.38, p < 0.05) and secondary progressive sample (adjusted R-2 of 0.280 and 0.183), respectively. Conclusions NBM damage is linked to cognitive impairment in PwMS.

Automated summary

NBM damage is associated with cognitive impairment in patients with multiple sclerosis, with diffusivity of NBM showing significant correlation with cognitive test results and ability to predict cognitive changes.