A longitudinal study of cognition in primary progressive multiple sclerosis

Abstract

There are few longitudinal studies of cognition in patients with multiple sclerosis, and the results of these studies remain inconclusive. No serial neuropsychological data of an exclusively primary progressive series are available. Cross-sectional analyses have revealed significant correlations between cognition and magnetic resonance imaging (MRI) parameters in primary progressive multiple sclerosis (PPMS). This study investigated cognitive and MRI change in 99 PPMS patients from five European centres for 2 years. They were assessed at 12 month intervals using the Brief Repeatable Battery, a reasoning test, and a measure of depression. The MRI parameters of T1 hypointensity load, T2 lesion load, and partial brain volume were also calculated at each time point. There were no significant differences between the mean cognitive scores of the patients at year 0 and year 2. However, one-third of the patients demonstrated absolute cognitive decline on individual test scores. Results indicated that initial cognitive status on entry into the study was a good predictor of cognitive ability at 2 years. There was only a small number of significant correlations between changes in cognition and changes on MRI, notably T1 hypointensity load with the two attentional tasks (r = -0.266, P = 0.017; r = -0.303, P = 0.012). It is probable that multiple factors underlie this weak relation between the cognitive and MRI measures.

Association of Neocortical Volume Changes With Cognitive Deterioration in Relapsing-Remitting Multiple Sclerosis

“…Previous longitudinal studies have highlighted the great interpatient variability in the cognitive outcome of patients with MS. However, a few well-designed longitudinal studies have consistently shown that nearly one third of patients deteriorate during 2-or 3-year follow-up periods 2,4,5,17 and the progression of cognitive dysfunction has been confirmed in a controlled 10-year observation. 3 In this study, we considered as deteriorating those patients who failed 1 or more tests compared with their baseline performance.…”

A multiparametric evaluation of regional brain damage in patients with primary progressive multiple sclerosis

“…The insula has numerous connections with the cerebral cortex (frontal lobe, temporal lobe, parietal lobe and anterior cingulate cortex), the basal ganglia, the amygdala and other areas that are part of the limbic system, such as the parahippocampal cortex. As a consequence its involvement in PPMS patients might contribute to explain, at least in part, deficits of cognitive function often encountered in these patients [Camp et al, 2005].…”

A 3-year longitudinal study of cognitive impairment in patients with primary progressive multiple sclerosis: Speed matters

“…A number of such studies have been published [8]. Their findings are highly inconsistent, with some studies documenting cognitive decline in at least a subset of the patients evaluated [9][10][11][12][13][14][15][16][17][18] and others offering little or no evidence of decline [19][20][21][22][23][24][25][26][27][28][29].…”

“…The most obvious distinction however is one of research design. The majority of these studies [12,13,17,21,23,24,[26][27][28] were uncontrolled and focused on the relationship between changes in patients' cognitive performance over time and brain imaging measures. Only six published reports of longitudinal studies [9][10][11][14][15][16] include a control group that was evaluated contemporaneously with the patient sample, and all of these studies provide evidence of cognitive deterioration in at least a subset of the patients.…”

“…JennekensSchinkel et al [15] showed that such patients were also more likely to drop out of longitudinal studies, thereby probably attenuating the extent of cognitive deterioration evident over time. Huijbregts et al [14] were the only investigators to compare cognitive decline in patients with different subtypes of MS. Because they specifically examined changes in patients with primary progressive MS, the study by Huijbregts et al [14] as well as an uncontrolled longitudinal study by Camp et al [12] is the most relevant to the present work and will be considered in greater detail in the Discussion section.…”