The Multiple Sclerosis Severity Score (MSSS) is a powerful method for comparing disease progression using single assessment data. The Global MSSS can be used as a reference table for future disability comparisons. While useful for comparing groups of patients, disease fluctuation precludes its use as a predictor of future disability in an individual.

We sought to identify clinical characteristics and socio-demographic variables associated with longitudinal patterns of fatigue in MS patients.A questionnaire including the Fatigue Severity Scale (FSS) was mailed to a community sample of 502 MS patients three times one year apart. Three patterns of fatigue were defined: persistent fatigue (PF) (mean FSS-score ≥5 at all time-points), sporadic fatigue (SF) (mean FSS-score ≥5 at one or two time-points) and no fatigue (mean FSS-score <5 at all time-points).Among the 267 (53%) patients who responded at all time points, 101 (38%, 95%CI 32-44) had persistent, 98 (37%, 95CI 31-43) sporadic and 68 (25%, 95%CI 20-31) no fatigue. Persistent and sporadic fatigue were more common in patients with, increased neurological impairment (p<0.001), primary progressive MS (p=0.01), insomnia (p<0.001), heat sensitivity (p<0.001), sudden-onset fatigue (p<0.001) or mood disturbance (p<0.001) compared to patients without fatigue. Multivariable analysis showed that depression (PF p=0.02, SF p<0.001), heat sensitivity (PF p=0.04, SF p=0.02), and physical impairment (PF p=0.004, SF p=0.01) were associated with both sporadic and persistent fatigue.

The Oslo Multiple Sclerosis (MS) Registry was established in 1990, and this is the first report on the prevalence and incidence of MS in the city of Oslo, Norway. The prevalence rate of definite MS on 1 January 1995 was 120.4/10(5). Inclusion of patients of native Norwegian ancestry only and exclusion of non-Norwegian immigrants yielded a prevalence rate of 136.0/10(5). A similar prevalence rate (136.5/10(5)) was found when patients and immigrants from the other Nordic countries (Finland, Sweden, Denmark) were included. Segregation of the native Norwegian patients according to the counties where they were born showed no significant differences except for a disproportionate increase of patients born in the inland county of Oppland. A total of 794 cases were resident in Oslo at the time of a diagnosis of definite MS in the period 1972-99. The crude average annual incidence rate for each 5-year period, between 1972 and 1996, increased significantly from 3.7/10(5) in the 1972-76 to 8.7/10(5) in the 1992-96 period. The increase was more marked in relapsing-remitting (RR) than in primary progressive disease and in female cases.

There are few studies of long-term, cause-specific mortality in multiple sclerosis (MS) relating to population mortality. Our objective was to study survival, excess mortality and causes of death in a cohort of patients with a long history of MS. Patients living in Oslo with definite MS and onset during 1940-80 were included in 2006. Causes of death and mortality in the general population were obtained from the Cause of Death Registry of Statistics Norway. Of the 386 patients included in the study, 263 (68%) had died at inclusion. Median survival from onset was 35 years (Kaplan-Meier: 95% confidence interval 33-37). Primary progressive MS was associated with shorter survival, but mean age at death was similar for relapsing-remitting and primary progressive MS patients. The most frequent underlying cause of death was MS (50%), and infection was often registered as a contributory cause (56%). The all-cause standardized mortality ratio was 2.47. Excess mortality was most marked during the second decade after onset of MS. We conclude that infections are probably the main cause of death in patients with MS, but the frequency is underestimated due to misleading information on death certificates. Excess mortality in patients with MS first appeared during the second decade of the disease. Survival seems to be age-dependent rather than related to disease course.

The prevalence of multiple sclerosis (MS) is increasing, and the presence of a latitude gradient for MS risk is still discussed. We present the first nationwide prevalence estimates for Norway, spanning the latitudes from 58-71 degrees North, in order to identify a possible latitude gradient. Information from the Oslo MS Registry and the Norwegian MS Registry and Biobank was combined with data from the Norwegian Patient Registry, the Norwegian Prescription Database and Statistics Norway. We estimated a crude prevalence of 203/100,000 on 1 January 2012. The prevalence in the Northern and Southern regions were not significantly different. MS prevalence in Norway is among the highest reported worldwide. We found no evidence of a latitude gradient.