Neuropsychological longitudinal study of patients with low-grade gliomas: Cognitive impairment.

This study is part of a longitudinal research program, in which patients diagnosed with low-grade gliomas (LGG: n = 13), as well as healthy controls (n = 13), were consecutively recruited and neuropsychologically followed for 7 years. The patients are followed up regardless of variations in treatment. A composite score is used (Global Deficit Score: GDS) included cognitive measures where at least five patients had a negative change: information processing speed, speed of naming, construction ability, verbal fluency, non-verbal thinking, and immediate non-verbal memory. The most important finding in this 7-year follow-up study is that two-thirds of the patients developed cognitive impairment. The remaining third of the patients showed stability in their cognitive ability and were still alive 17 years after diagnosis. Younger patients with tumors in the right frontal or posterior regions showed a more favorable development. Patients with frontal tumors and a declined GDS show also significant changes in executive functions. Given the limited number, no firm conclusions can be drawn regarding the impact of tumor localization. The impact of LGG on cognition and the survival time after diagnosis varies considerably between patients. However, most of the patients (69%) showed cognitive impairment during the seven years we followed them.

Decline in executive functions and speed in suspected low-grade gliomas: A 3-year follow-up of a clinical cohort.

Changes over time in information processing speed and executive functions (EFs) were studied in patients with suspected low-grade gliomas (LGG) 3 years after diagnosis. Using a person-oriented approach, the study aimed at focusing solely on two cognitive domains known to be significant in the understanding of the impact of white matter diseases. The Barkley's hybrid model of EFs was used as a theoretical framework for the evaluation of EFs. The majority of the patients showed a decline in at least one of these two cognitive domains indicating that the progress of diffuse brain injury cannot be neglected in understanding neuropsychological changes over time in patients with LGG. In our sample, higher age and radiological signs of radiotherapy-induced brain atrophy were seen in patients with a decline in both domains.

Early cognitive impairment in a subset of patients with presumed low-grade glioma.

We investigated the presence of cognitive impairment, in adults with presumed low-grade glioma at early stage of disease prior to major treatments, in relation to neurological symptoms and radiological characteristics of the tumour. Sixteen patients were evaluated. A subset of patients was identified with clearly impaired cognition. Patients with cognitive impairment often had large tumours in the left frontal lobe, were relatively young, and most of them were males. We conclude that cognitive dysfunction may be present already at early stage of disease, and that early identification of patients at risk is warranted.

Pitfalls in the assessment of disability in individuals with low-grade gliomas.

In this study, the presence of motor and cognitive disability is described in a cohort of patients with low-grade glioma recruited from a geographical area with a well-defined population located in the middle of Sweden. The study group consisted of 35 patients, of which 24 were evaluated by both a neurologist and a neuropsychologist, and 11 only by a neurologist. The test battery according to EFIT (Edinburgh Functional Impairment Test) was used by the neurologist to measure impairments of limb function, memory and speech. Patients were asked to self-evaluate their deficits in motor function and cognition by responding to a specific questionnaire. In addition, a neuropsychological test battery was used by an experienced neuropsychologist who had no previous contact with the patients. In general, motor impairment was mild and predominantly found in the upper limb. Neuropsychological assessment revealed moderate or severe cognitive impairment in more than half of the patients. This impairment was not detected by neurological examination, and only to some extent reported by the patients them selves. The results show statistical differences in cognitive function, memory and language as recorded by the three assessors. In conclusion, this study demonstrates the usefulness of neuropsychological assessment as a complement to neurological examination to detect cognitive dysfunction in patients with low-grade gliomas.