MRI findings in benign multiple sclerosis are variable

Clinical trials in multiple sclerosis: potential future trial designs

Clinical trials of new treatments in multiple sclerosis (MS) currently require large sample sizes and long durations in order to yield reliable results. The differential responses of an already heterogeneous population of MS patients to individual disease-modifying therapies (DMTs) will further complicate future trials. MS trials with smaller samples and faster outcomes are conceivable through the substitution of current clinical and MRI outcomes with objectively measureable genomic and proteomic biomarkers. Currently, biomarkers that could be utilized for diagnosis and monitoring of MS disease activity are in the early validation phase. The power of single biomarkers or multiple correlated biomarkers to predict prognosis and response to treatment could initially be compared with currently accepted methods. These prospectively validated disease biomarkers could then be used to subcategorize the spectrum of MS patients into a finite number of endophenotypes with demonstrable different molecular pathogeneses and DMT response profiles. Newly developed DMT could potentially be assessed within specific endophenotypes and compared with pharmacogenomically relevant active comparator DMT. This approach may increase the efficiency of MS trials through homogenization of patient population and minimization of nonresponders in study groups, providing the potential for the development of targeted therapies.

The psychosocial and cognitive impact of longstanding 'benign' multiple sclerosis

BACKGROUND

Benign multiple sclerosis (BMS) is typically defined using the Expanded Disability Status Scale (EDSS), which relies heavily on ambulation. We set out to examine important psychosocial and cognitive outcomes in patients with longstanding BMS compared with patients who had recently progressed to 'no longer benign' (NLB).

METHODS

A previously reported cohort of BMS (EDSS ≤3 at 20 years disease duration) were re-assessed 25-30 years post-onset. Patients remaining benign (EDSS ≤3 at re-assessment) were compared with those NLB for: depression (Beck Depression Inventory), fatigue (Modified Fatigue Impact Scale), health-related quality of life (MSQoL-54), cognition (Rao's Neuropsychological Screening Battery), and employment status.

RESULTS

A total of 75% (66/88) of the original cohort were located. A total of 61 patients were re-assessed. Twenty-five patients (41%) had progressed in EDSS and were NLB. Compared with benign patients, those NLB were more likely to have: significant fatigue (15/36 [42%] vs. 18/25 [72%], p = 0.019); poorer physical functioning (mean MSQoL-54 = 67.30 vs. 50.89, p = 0.002); an MS-related negative change in employment status (13/36 [36%] vs. 21/25 [84%], p < 0.0001) and cognitive impairment (3/28 [11%] vs. 5/19 [26%]; trend only, p = 0.317). Depression and mental health quality if life differed little between the benign and NLB patients (p > 0.6).

CONCLUSIONS

Despite remaining benign for 20 years, a significant proportion of patients progressed with further follow up. While neither depression nor patient-reported mental health quality of life was associated with EDSS progression, patients with longstanding 'benign' MS (EDSS ≤3 for 25+ years) had less fatigue, better physical quality of life and employment outcomes and infrequent cognitive impairment. Remaining benign over the long term, as defined by the EDSS, carried some advantages beyond ambulation.

Relationship between brain MRI lesion load and short-term disease evolution in non-disabling MS: a large-scale, multicentre study

BACKGROUND AND OBJECTIVES

We evaluated clinical and conventional MRI features of a large population of patients with non-disabling MS to identify potential markers of a benign disease course.

METHODS

In seven MAGNIMS centres we retrospectively identified 182 patients with benign (B) MS (EDSS score ≤ 3.0, disease duration ≥ 15 years) and 187 patients with non-disabling relapsing-remitting MS (NDRRMS) (Expanded Disability Status Scale score ≤ 3.0, disease duration between 5 and 14 years), in whom clinical data were collected within two weeks from a brain T2-weighted scan. Brain T2 lesion volume (LV) was measured in all patients. In 146 BMS and 146 NDRRMS patients, clinical data were also available after a median follow up of 29 months (range: 7-104 months).

RESULTS

Mean LV was higher in BMS than in NDRRMS patients (p<0.001), but the mean ratio between LV and disease duration was higher in NDRRMS than in BMS patients (1.1 vs. 0.6 ml/year, p<0.001). In BMS patients, brain LV was correlated with EDSS score increase at follow up (r=0.18, p=0.03).

CONCLUSIONS

An overall low rate of brain LV increase during a long-lasting disease course might be a feature of BMS. In BMS patients, a high brain LV might be associated with worsening of locomotor disability at short-term follow up.

Corpus callosum damage and cognitive dysfunction in benign MS

Corpus callosum (CC), the largest compact white matter fiber bundle of the human brain involved in interhemispheric transfer, is frequently damaged in the course of multiple sclerosis (MS). Cognitive impairment is one of the factors affecting quality of life of patients with benign MS (BMS). The aim of this study was to investigate the relationship between the cognitive profile of BMS patients and the extent of tissue damage in the CC. Brain conventional and DT MRI scans were acquired from 54 BMS patients and 21 healthy controls. Neuropsychological tests (NPT) exploring memory, attention, and frontal lobe cognitive domains were administered to the patients. DT tractography was used to calculate the mean diffusivity (MD) and fractional anisotropy (FA) of the CC normal appearing white matter (NAWM). An index of CC atrophy was also estimated. Nine (17%) BMS patients fulfilled criteria for cognitive impairment. Compared with controls, BMS had significantly different CC diffusivity and volumetry (P < 0.001). Compared with cognitively preserved patients, those with CI had significantly higher CC lesion volume (LV) (P = 0.02) and NAWM MD (P = 0.02). The scores obtained at PASAT were significantly correlated with CC T2 LV, and NAWM FA and MD (r values ranging from -0.31 to 0.66, P values ranging from 0.04 to <0.001). Cognitive impairment in BMS is associated with the extent of CC damage in terms of both focal lesions and diffuse fiber bundle injury. MRI assessment of topographical distribution of tissue damage may represent a rewarding strategy for understanding the subtle clinical deficits of patients with BMS.