Cerebral glucose metabolic correlates of cognitive and behavioural impairments in amyotrophic lateral sclerosis

• Published in: Journal of neurology Vol. 271; no. 8; pp. 5290 - 5300
• Main Authors: Lehto, Annaliis, Schumacher, Julia, Kasper, Elisabeth, Teipel, Stefan, Hermann, Andreas, Kurth, Jens, Krause, Bernd Joachim, Prudlo, Johannes
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2024; Springer Nature B.V
• Subjects: Amyotrophic lateral sclerosis; Cognition & reasoning; Glucose; Glucose metabolism; Medicine; Medicine & Public Health; Metabolism; Neurology; Neuroradiology; Neurosciences; Original Communication; Positron emission tomography; Social interactions; Statistical analysis; Substantia grisea; FDG-PET; Amyotrophic lateral sclerosis; Cognition; Cerebral glucose metabolism; Grey matter volume
• ISSN: 0340-5354; 1432-1459; 1432-1459
• DOI: 10.1007/s00415-024-12388-z

Objective Half of ALS patients are cognitively and/or behaviourally impaired. As cognition/behaviour and cerebral glucose metabolism can be correlated by means of 18 F-Fluorodeoxyglucose positron emission tomography (FDG-PET), we aimed to utilise FDG-PET, first, to replicate group-level differences in glucose metabolism between non-demented ALS patients separated into non-impaired (ALSni), cognitively impaired (ALSci), behaviourally impaired (ALSbi), and cognitively and behaviourally impaired (ALScbi) groups; second, to investigate glucose metabolism and performance in various cognitive domains; and third, to examine the impact of partial volume effects correction (PVEC) of the FDG-PET data on the results. Methods We analysed neuropsychological, clinical, and imaging data from 67 ALS patients (30 ALSni, 21 ALSci, 5 ALSbi, and 11 ALScbi). Cognition was assessed with the Edinburgh Cognitive and Behavioural ALS Screen, and two social cognition tests. FDG-PET and structural MRI scans were acquired for each patient. Voxel-based statistical analyses were undertaken on grey matter volume (GMV) and non-corrected vs. PVE-corrected FDG-PET scans. Results ALSci and ALScbi had lower cognitive scores than ALSni. In contrast to both ALSni and ALSci, ALScbi showed widespread hypometabolism in the superior- and middle-frontal gyri in addition to the right temporal pole. Correlations were observed between the GMV, the FDG-PET signal, and various cognitive scores. The FDG-PET results were largely unaffected by PVEC. Interpretation Our study identified widespread differences in hypometabolism in the ALScbi-ni but not in the ALSci-ni group comparison, raising the possibility that cerebral metabolism may be more closely related to the presence of behavioural changes than to mild cognitive deficits.