Multiple sclerosis in Vest-Agder County, Norway

Vatne A., Mygland Å., Ljøstad U. Multiple sclerosis in Vest‐Agder county, Norway.
Acta Neurol Scand: 2011: 123: 396–399.
© 2010 John Wiley & Sons A/S. Objective – To examine multiple sclerosis (MS) prevalence, rate of immunomodulatory treatment and frequency of Borrelia Burgordorferi (Bb) antibodies in Vest‐Agder, Norway. Materials and methods – Patients in the period 1996–2006 who met the Poser criteria for definitive or probable MS were included. Clinical and demographical data, and presence of Bb antibodies were registered. Results – A total of 295 patients were identified. The crude prevalence was 180 per 100,000 population (95% CI = 160.9–218.0), age‐adjusted prevalence was 186 per 100,000 population (95% CI = 166.3–225.3). The age‐adjusted incidence rates were 7.5 and 8.0 for 1996–2000 and 2001–2006, respectively. Thirty‐eight per cent were treated with immunomodulatory agents when compared to 28% in the rest of the country. Bb serum antibodies were detected in 7% of patients with MS. Conclusions – Vest‐Agder county has the highest prevalence of MS reported in Norway, and a high treatment rate. Bb antibodies were not more prevalent than in healthy individuals.     

Increasing prevalence of multiple sclerosis in Finland

Objectives – To follow‐up the prevalence trends of MS from 1983 to 1993 in western and southern Finland. MS epidemiology has been previously followed from 1964 to 1978 in these regions. The updated prevalences were correlated with incidence trends in the same period. Methods– Age‐adjusted and age‐specific MS prevalence rates were calculated for cases classified by Poser's criteria. Results– In the western health‐care districts, Seinäjoki and Vaasa, prevalences in 1993 were 202/10⁵ and 111/10⁵. In the southern district Uusimaa the respective figure was 108/10⁵. In Seinäjoki a significant 1.7‐fold increase was found in 1993 as compared to 1983, mainly due to increased incidence. In Uusimaa a significant 1.2‐fold increase in prevalence was found in the presence of stable incidence. In Vaasa prevalence was stable, although incidence was declining. Conclusion– The prevalence of MS is increasing in Seinäjoki and Uusimaa but not in Vaasa. Both the prevalence and incidence in Seinäjoki are now among the highest reported.     

Multiple sclerosis in the two northernmost counties of Norway

The prevalence of MS in the two northernmost counties of Norway increased from 20.6 per 100,000 in 1973 to 31.5 per 100,000 in 1983, the increase being most marked in women. The average annual incidence seems to have been stable over the past 20-30 years. None of the patients had a pure Lapp background (having a Lapp mother and father).     

Methisoprinol in the treatment of multiple sclerosis.

Twenty-five patients affected by remittent form of multiple sclerosis (MS) were treated with methisoprinol for a period of 2 years. The clinical parameters, recorded during a 2-year observation period preceding onset of therapy, were compared with the analogous measures recorded during treatment. Treatment was associated with significant favourable changes. In fact, there were observed: a reduction in mean annual relapse rate for 22 of 25 patients; an improvement in the clinical status as demonstrated by the reduction of the Kurtzke Disability Status Scale values obtained in 14 of 25 patients; a reduction in the mean period of standard corticosteroid therapy.     

Diagnosis and treatment of multiple sclerosis

Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system that usually has onset between 20 and 40 years of age. The causes of MS are unknown, but it probably evolves among genetically susceptible individuals as an infrequent response to environmental factors. The diagnosis is based on careful evaluation of the disease history, clinical examination as well as paraclinical examination, aiming to document disseminated disease in both time and space. No cure is available, but corticosteroids can be used for relapses, various symptomatic treatments exist, and several long-term, disease-modifying therapies are available. This article reviews the diagnosis and treatment of MS, focusing on treatment of relapses and disease-modifying therapies.     

Marked differences in prevalence of multiple sclerosis between ethnic groups in Oslo,Norway

Objectives

Oslo, the capital of Norway, has a high prevalence of multiple sclerosis (MS). In recent decades there has been substantial immigration to Oslo from Asia, the Middle East and Africa. The aim of the study was to estimate the prevalence of MS among non-Western immigrants living in Oslo, adjusted for duration of residence.

Methods

Data were obtained from the MS registry at Ullevål University Hospital. The prevalence of MS was adjusted for ethnicity, age and duration of residence in Norway.

Results

A total of 786 definite MS patients were alive and resident in Oslo on 31 December 2005, yielding a crude prevalence of 148/10⁵. Twentyseven patients were of non-Western origin: Middle East 14, Asia 9, Africa 4. The non-Western patients' mean age at migration was 20. The crude prevalence (95 % CI) of MS patients was 170/10⁵ (159–182) for the Norwegian/Western, 85/10⁵ (50–143) for the Middle East, 21/10⁵ (11–41) for the Asian, and 20/10⁵ (7–53) for the African cohorts. The high MS prevalence in the Middle East cohort and the low prevalence among Asian/African immigrants were also pronounced after adjustment for age and duration of residence.

Conclusions

The Middle East immigrants had a markedly higher prevalence of MS despite a shorter duration of residence than other non-Western patients. These findings suggest that people from the Middle East have a greater genetic disposition for MS. Furthermore, the high age at migration among the non-Western immigrants indicates that possible environmental factors affecting MS risk may also act on adults.

     

An epidemiological study of multiple sclerosis in central Sardinia, Italy

Objectives – To verify morbidity estimates in central Sardinia, Italy. Methods – A prevalence study was performed in the province of Nuoro, Central Sardinia, which has a population of 273,768 inhabitants (135,383 men and 138,385 women). A complete enumeration approach was adopted by using all possible case-collection sources. Results – On prevalence day, December 31, 1993, 394 subjects (124 men and 270 women) living in the study area were known to suffer from definite and probable MS, giving a crude prevalence rate of 143.9 cases per 100,000 people, 91.6 for males and 195.11 for females. The crude prevalence estimated on December 31, 1985, based on 282 MS cases alive in the study area, was 102.94 per 100,000. Conclusion – This study reinforced central Sardinia's position as a high and rising prevalence area for MS.     

The frequency of multiple sclerosis in Mediterranean Europe

Recent investigations on multiple sclerosis (MS) distribution in Italy, based on relatively small population groups, contradict the current thesis, derived from studies undertaken in populations exceeding 300,000, of a lower spreading of the disease in Mediterranean Europe. Intensive surveys on small populations strengthen the suggestion that Italy is a high-risk area, although MS studies based on prevalence rather than incidence could also be biased by geographic variables making prevalence unsuitable for comparing MS prevalence rates found in different years and/or zones. We report a further epidemiologic study in Barbagia, Sardinia, insular Italy, undertaken both to establish the MS incidence in the last 20 years, and to estimate a new prevalence rate. Based on 31 probable incident cases, the mean incidence per year for the years 1961-1980 was 2.9 per 100,000 (3.2 if age- and sex-standardized to the Italian population). On October 24, 1981, the prevalence per 100,000 was 65.3 (77.9 if standardized to the Italian population). These results confirm that in Barbagia, MS occurs more frequently than expected in a Mediterranean area, and give further support to the idea that MS frequency in Italy is similar to that established for most central and northern European countries.     

Prevalence of multiple sclerosis in Belgrade, Yugoslavia

OBJECTIVES: To estimate the distribution of multiple sclerosis in the Belgrade population. METHODS: All persons who were affected and/or died from multiple sclerosis (Poser's criteria), with residence in the Belgrade region had been collected from January 1, 1985 to December 31, 1996. Prevalence was adjusted by direct method, using world population. RESULTS: From 1985 to 1996, 823 patients were suffering from multiple sclerosis. Sex ratio was 1:1.9. The mean age at onset was 32.2 +/- 9.8 years. A relapsing-remitting course of multiple sclerosis was reported in 50.7% patients, secondary progressive in 36.4%, patients, and primary progressive in 12.9% patients. On December 31, 1996, age-adjusted prevalence of multiple sclerosis in Belgrade was 41.5/100,000, 28.2/100,000 for males, and 54.1/100,000 for females. During the period studied, statistically highly significant increasing trend of multiple sclerosis prevalence was observed (P = 0.0001). CONCLUSIONS: According to findings presented in this study, Belgrade is an area with high prevalence of multiple sclerosis.     

Epidemiology of multiple sclerosis in northern Greece

A total of 638 new cases of multiple sclerosis (MS) (365 females, 273 males) were found from 1970-1984 in northern Greece (Macedonia and Thrace); the average annual incidence rate was 1.79 per 100,000 inhabitants with increasing incidence from 1980-1984. A total of 729 people living in northern Greece suffered from MS on December 31, 1984 (prevalence rate 29.5 per 100,000 inhabitants). No difference was found between urban and rural areas. No difference from the international standards was found for sex incidence. The study confirms the quite high prevalence of MS despite the fact that northern Greece is in the intermediate risk zone.     

Tremor in multiple sclerosis

Tremor is estimated to occur in about 25 to 60 percent of patients with multiple sclerosis (MS). This symptom, which can be severely disabling and embarrassing for patients, is difficult to manage. Isoniazid in high doses, carbamazepine, propranolol and gluthetimide have been reported to provide some relief, but published evidence of effectiveness is very limited. Most trials were of small size and of short duration. Cannabinoids appear ineffective. Tremor reduction can be obtained with stereotactic thalamotomy or thalamic stimulation. However, the studies were small and information on long-term functional outcome is scarce. Physiotherapy, tremor reducing orthoses, and limb cooling can achieve some functional improvement. Tremor in MS remains a significant challenge and unmet need, requiring further basic and clinical research. Received in revised form: 2 May 2006     

A further study on the prevalence of multiple sclerosis in Sicily: Caltanissetta city

The prevalence of probable multiple sclerosis (MS) in Caltanissetta city, Sicily, is at least 51 per 100,000. If possible multiple sclerosis patients are included, it is 54 per 100,000. This value is similar to that found in other cities in Sicily: Enna, Monreale and Agrigento. The high prevalence of multiple sclerosis in Caltanissetta confirms the previous data on Sicily and emphasises the importance of small population studies in the epidemiology of MS.     

Multiple sclerosis in Oslo, Norway: prevalence on 1 January 1995 and incidence over a 25-year period

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.     

Disability and mortality in multiple sclerosis in Western Norway

Introduction – Continued studies of frequency trends in carefully selected sites around the world can provide clues to the cause of multiple sclerosis (MS). Material and methods – Based on information from three different, semi-independant sources of information, we have examined the temporal trends in the average annual age-adjusted rates of disability pension incidence, mortality, and incidence of MS from 1966 to 1991 in More and Romsdal County, Norway. Results – The average annual age-adjusted disability pension incidence rates (1966–68 = 3.62/100,000; 1990–91 = 7.33/100,000), the mortality rates (1966–68=0.91/100,000; 1990–91 = 1.88/100,000), and the incidence rates (1966–68 = 4.22/100,000; 1990–91 = 5.02/100,000) all showed a statistically significant increase. The difference in the development of MS-specific disability pension prevalence rates in the county compared to the nation is notable. Conclusions – We consider that the increase in disability pension incidence, mortality, and incidence of MS is of biological significance. Thus three different sources of information corroborate corresponding trends indicating that better case ascertainment and improved diagnostic facilities only partially can explain the reported MS increase in western Norway.     

The basis for treatment in multiple sclerosis

Contemporary licensed treatments for multiple sclerosis fail to provide a solution for the disease because their effects are limited to a modest reduction in the frequency of new episodes. They do not reduce disability or materially influence the progressive phase of the disease. A contemporary strategy for management requires a more detailed analysis of the separate contributions to the clinical features and overall course made by inflammation, axonal injury, compensatory mechanisms, and remyelination. From this formulation emerges the need either for early and fully effective suppression of the inflammatory response, limiting the damage to all components of the axon-glial unit; or the development of strategies for axonal and myelin repair that solve the issues of controlled differentiation, delivery and timing of these cell and growth factor-based interventions.     

Prevalence and incidence of multiple sclerosis in Oppland County: a cross-sectional population-based study in a landlocked county of Eastern Norway

Risberg G, Aarseth JH, Nyland H, Lauer K, Myhr K‐M, MidgardR. Prevalence and incidence of multiple sclerosis in Oppland County – a cross‐sectional population‐based study in a landlocked county of Eastern Norway.
Acta Neurol Scand: 2011: 124: 250–257.
© 2010 John Wiley & Sons A/S. Objectives – We report the prevalence and incidence rates of multiple sclerosis (MS) in Oppland County, Norway. Methods – Records from all patients diagnosed with MS at the two Oppland County hospitals, Gjøvik and Lillehammer during 1989–2001 were evaluated. In addition, all general practitioners in Oppland County reported their patients into the study. Results – The age‐adjusted prevalence rate of definite MS was 174.4/ 100 000 on the prevalence day 1 January 2002. When the probable cases were included, the prevalence rate rose to 185.6/100 000. The highest prevalence rates were detected in the northern mountain areas, thus corroborating the results from previous local surveys 30–50 years ago. The prevalence of MS was statistically significantly associated with climatic, socioeconomic and geographic variables in the county. The age‐adjusted incidence of definite and probable MS in Oppland County was 6.6/100 000 during 1989–1993 increasing to 7.6/100 000 during 1994–1998. Discussion – We found the highest prevalence rates of MS ever reported in Norway. Our findings indicate a possible influence of environmental factors.