Oluf Andersen

Viral infections trigger multiple sclerosis relapses: a prospective seroepidemiological study

A neurological surveillance was combined with prospective recording of upper respiratory and gastrointestinal infections and serological diagnosis of five common viral infections in 60 benign multiple sclerosis patients, with a mean follow-up of 31 months. During 4-week at risk (AR) periods encompassing common infections, a significant excess of MS relapses was found in the AR period, with a relative risk of 1.3. A seasonal variation of the MS relapse rate was found with a minimum in summer. There was a significant correlation between the number of AR relapses and the number of common infections per month explaining the periannual distribution of relapses. The non-AR relapses showed no seasonal variation. There was a significant correlation between adenovirus CF titre rises associated with upper respiratory infections and the occurrence of a major MS relapse in the AR period (n = 7), while influenza infections were not followed by a major MS relapse (n = 6). Linear homologies have been demonstrated between adenovirus and basic myelin protein. The epidemiological approach is essential to our understanding of systemic antigens triggering multiple sclerosis activity.

Neurofilament light protein and glial fibrillary acidic protein as biological markers in MS

Objective: To determine if CNS-derived proteins present in the CSF of multiple sclerosis (MS) patients reflect different pathologic processes of MS and if these proteins could be useful as biologic markers of disease activity. Methods: Concentrations of the neurofilament light protein (NFL), glial fibrillary acidic protein (GFAP), S100B, and the neuron-specific enolase protein (NSE) were determined in the CSF of 66 MS patients and 50 healthy control subjects with immunoassays. Results: The mean levels of the NFL were increased during all stages of MS compared with controls (p < 0.001), peaking almost 10 times higher during acute relapses. The highest levels of GFAP were found during the secondary progressive course (p < 0.001) with a strong correlation with neurologic deficits (Expanded Disability Status Scale score, r = 0.73, p < 0.001). No increase of S100B or NSE protein was found in the CSF of MS patients compared with control subjects. Conclusions: Increased level of NFL is a general feature of MS, indicating continuous axonal damage during the entire course of the disease with the most profound damage during acute relapses. GFAP may serve as a biomarker for disease progression, probably reflecting the increasing rate of astrogliosis.

Neurofilament protein in cerebrospinal fluid: a potential marker of activity in multiple sclerosis

The neurofilament protein is a major structural protein of neurons and a marker for axonal damage. The concentrations of the light subunit of the neurofilament triplet protein (NFL) in CSF were significantly increased in patients with relapsing-remitting multiple sclerosis compared with healthy controls (p<0.001). Seventy eight per cent of patients with multiple sclerosis showed increased NFL concentrations. Significant correlations between the NFL concentration in CSF and clinical indices were discerned for disability, exacerbation rate, and time from the start of the previous exacerbation to the time of the lumbar puncture. The results suggest that axonal damage occurs during relapsing-remitting multiple sclerosis and that the damage contributes to disability and the appearance of clinical exacerbations. The concentration of NFL in CSF is a potential marker of disease activity in multiple sclerosis and might be useful in future clinical trials of multiple sclerosis.

Long-term follow up of patients with clinically isolated syndromes, relapsing-remitting and secondary progressive multiple sclerosis.

This paper extends on previous data on prognosis in multiple sclerosis (MS), to encompass the entire course of the disease. The first episode suggestive of MS [the clinically isolated syndrome (CIS)] was included as a starting point, and the speed of secondary progression as an end point. Primary progressive MS was not included. Unique preconditions, with one neurological service covering the G öteborg district, allowed for establishing a strictly population-based, essentially untreated 15-year incidence cohort of 308 MS patients who were followed for 25 years. Survival analysis was performed as Kaplan -Meyer graphs, and independent predictors were ascertained by C ox regression analysis. A matrix of several predictors and end points was created. From C IS, a higher risk of developing clinically definite MS (C DMS), secondary progressive course and Disability Status Scale 7 (DSS7) was predicted by efferent tract lesions. However, less than 25% had reached DSS7 25 years after C IS with pure afferent lesions or other favorable predicto rs. During the first five years, higher relapse frequency, as well as incomplete remission of early bouts, predicted higher risks of secondary progressive course and DSS7 during follow-up to 25 years. However, these early predictors were unable to predict the rate of progression, which seems to contain an element of the disease process unassociated with its early events. O nly late predictors, such as a shorter time from onset to secondary progression (1-10 years) and a higher number of functional systems involved at onset of progression predicted a faster progression rate. Predictors from this study could be used to refine historically controlled trials.

Acyclovir treatment of relapsing-remitting multiple sclerosis. A randomized, placebo-controlled, double-blind study.

Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on “intent-to-treat” data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation.

Linomide reduces the rate of active lesions in relapsing-remitting multiple sclerosis

The synthetic immunomodulator Linomide, a quinoline-3-carboxamide, has a profound inhibitory influence in several experimental autoimmune diseases, including acute and chronic experimental allergic encephalomyelitis. In a double-blind trial, 31 patients with relapsing-remitting multiple sclerosis were randomized to oral doses of 2.5 mg Linomide or placebo once a day for six months. Fourteen patients receiving Linomide and 14 receiving placebo completed the trial, and the results were based on this population. The mean number of active (new and enlarged T2 weighted) lesions per monthly MRI scan was 1.37 in the patients receiving Linomide and 4.22 in the patients receiving placebo (p = 0.043). The percentage of scans with active MRI lesions was lower in the Linomide-treated group (p = 0.0064). When neurologic deficit was assessed by the Regional Functional Scoring System (RFSS), the Linomide group showed an improvement of 1% of the maximal RFSS range and the placebo group a deterioration of 0.2% (p = 0.14). There were three patients with relapses in the Linomide-treated group and six in the placebo group (p = 0.22). A slightly decreased proportion of natural killer cells in cerebrospinal fluid and peripheral blood was noted in the Linomide group. A severe adverse event of pleuropericarditis occurred in one of the Linomide-treated patients. The most frequent adverse event was musculoskeletal pain, of mild to severe degree, which tended to diminish after three months on Linomide therapy. NEUROLOGY 1996;47: 895-900

Incidence of MS during two fifteen-year periods in the Gothenburg region of Sweden

The average annual incidence of definite and probable MS in Gothenburg was re‐investigated. For 1950–1954, 1955–1959 and 1960–1964 it was 4.2, 4.2 and 4.3/100,000/year. For the five‐year periods between 1974 and 1988 it was 3.0, 2.7 and 2.0/100,000/year. If possible MS was included, the corresponding incidence for 1950–1964 was 5.2, 5.3 and 5.1, and for 1974–1988 it was 3.9, 3.9 and 4.3/100,000/year. Neurological methods and diagnostic criteria were constant throughout the period. The 1950–1964 incidence was based on personally investigated cases, while the 1974–1988 incidence was based partly on review of Gothenburg neurology records. It is concluded that there has been a significant decrease in the incidence of MS in this area. However, the notified decrease may partly be explained by alterations in the case ascertainment procedure. Since the Swedish measles vaccination program started in 1971, the occurrence of measles has been declining and has practically ceased during the 1980s. The time when a possible influence of mass vaccinations against childhood diseases on MS incidence can be monitored is discussed.

Multicentre, randomised, double blind, placebo controlled, phase III study of weekly, low dose, subcutaneous interferon beta-1a in secondary progressive multiple sclerosis

Objective: Interferon (IFN) beta has repeatedly shown benefit in multiple sclerosis (MS) in reducing the rate of relapse, the disease activity as shown with magnetic resonance imaging and, to some degree, the progression of disability; however, it is unknown how much the therapeutic response depends on the dose, the subgroup involved, and the disease stage. This multicentre, double blind, placebo controlled study explored the dose−response curve by examining the clinical benefit of low dose IFN beta-1a (Rebif®), 22 μg subcutaneously once weekly, in patients with secondary progressive MS. Methods: A total of 371 patients with clinically definite SPMS were randomised to receive either placebo or subcutaneous IFN beta-1a, 22 μg once weekly, for 3 years. Clinical assessments were performed every 6 months. The primary outcome was time to sustained disability, as defined by time to first confirmed 1.0 point increase on the Expanded Disability Status Scale (EDSS). Secondary outcomes included a sensitive disability measure and relapse rate. Results: Treatment had no beneficial effect on time to confirmed progression on either the EDSS (hazard ratio (HR) = 1.13; 95% confidence interval (CI) 0.82 to 1.57; p = 0.45 for 22 μg v placebo) or the Regional Functional Status Scale (HR = 0.93; 95% CI 0.68 to 1.28; p = 0.67). Other disability measures were also not significantly affected by treatment. Annual relapse rate was 0.27 with placebo and 0.25 with IFN (rate ratio = 0.90; 95% CI 0.64 to 1.27; p = 0.55). The drug was well tolerated with no new safety concerns identified. No significant gender differences were noted. Conclusions: This patient population was less clinically active than SPMS populations studied in other trials. Treatment with low dose, IFN beta-1a (Rebif®) once weekly did not show any benefit in this study for either disability or relapse outcomes, including a subgroup with preceding relapses. These results add a point at one extreme of the dose−response spectrum of IFN beta therapy in MS, indicating that relapses in this phase may need treatment with higher doses than in the initial phases.

Lymphocyte phenotype and subset distribution in normal cerebrospinal fluid.

The distribution of lymphocyte subpopulations in cerebrospinal fluid (CSF) and their phenotypic characteristics were extensively investigated in a group of 18 healthy individuals using two- and three-color flow cytometry. Generally, CD3+ T lymphocytes constituted the vast majority of CSF lymphocytes while the number of B lymphocytes and NK cells were low. Most T lymphocytes exhibited the phenotype of memory/primed cells in both the CD4+ and CD8+ subpopulations. Two markers for recent activation, HLA-DR and interleukin-2 receptor (CD25) were not upregulated when compared with peripheral blood (PB) in the majority of CSF T lymphocytes. However, a fraction of T lymphocytes co-expressing the NK cells markers CD56 and/or CD16 showed a pronounced upregulation of HLA-DR in CSF as compared with PB. This study documents that the cellular composition of the normal CSF differs profoundly from PB regarding all major lymphocyte subpopulations. This has to be taken into account in studies addressing questions regarding cellular immune reactions in the central nervous system under pathological conditions.

Glial fibrillary acidic protein in CSF of multiple sclerosis patients: relation to neurological deficit

Glial fibrillary acidic protein (GFAp) was analysed in cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) and healthy controls. Patients with relapsing-remitting course (n = 13) were followed with quantitative neurological examinations and lumbar punctures during a 24-month period. The patient group was a subsample from a randomised, double-blind clinical trial of acyclovir on MS: 7 patients were treated with acyclovir and 6 were placebo controls. CSF was also collected from 5 age-matched healthy individuals with normal quantitative neurological examinations. The CSF assays disclosed increased concentrations of GFAp in MS patients compared to controls (p < 0.01). Furthermore, the GFAp levels correlated significantly with the deficit score (p < 0.01) but not with exacerbation frequency. When the group treated with acyclovir was compared with the placebo group, no significant change of CSF GFAp was observed. In the present study we show that GFAp is increased in CSF of patients with MS and that the levels correlate with the neurological dysfunction. Further work is needed to ascertain whether determinations of CSF GFAp can be used to monitor disease progression in MS or whether the assay may be useful to evaluate therapeutic intervention.