A possible spatial and temporal cluster of multiple sclerosis in the town of Linguaglossa,Sicily

We carried out an epidemiological survey to determine prevalence and incidence of multiple sclerosis in the little town of Linguaglossa in the Province of Catania. We calculated prevalence rate as point prevalence at 1 January 2001 and incidence during 1991–2000.We studied the frequency of multiple sclerosis in the community of Linguaglossa in a population of 5,422 inhabitants in the 2001 census. The primary sources for the case ascertainment were the general practitioners of Linguaglossa, the local Italian Multiple Sclerosis Association and the neurological departments, Multiple Sclerosis Centers and private neurologists of the province of Catania. We considered as prevalent and incident cases all patients who satisfied the Poser’s diagnostic criteria. We detected 11 patients with multiple sclerosis who had had the onset of disease on prevalent day (P.D.). The onset–adjusted prevalence rate was 203/100,000 (95% CI 107–352).Prevalence was higher in women (247/100,000) than in men (154/100,000). From 1991 to 2000, 10 subjects with MS had clinical onset of disease. The mean annual incidence risk was 18.2/100,000 (C. I. 95 % 5.9–42.5).Conversely in the same population prevalence on 1 January 1991 was 37/100,000 while the onset adjusted annual incidence risk during the previous decade (1981–1991) was 3.6/100,000. Prevalence and incidence rates of MS during the last decade in the little town of Linguaglossa are higher than those found in the same area during the previous ten years and also than those reported in other Sicilian and Italian surveys suggesting a possible cluster of MS.     

The epidemiology of motor neurone disease in two counties in the southwest of England

The epidemiology of motor neurone disease (MND) in the counties of Devon and Cornwall in the southwest of England has not previously been studied. A previous study of England and Wales has, however, reported a very high death certification rate of MND in Devon. This study was carried out to establish the prevalence and incidence of MND in Devon and Cornwall and make comparisons with published rates in other populations. We attempted to identify all cases of MND diagnosed in Devon and Cornwall between 2002 and 2007. Case identification was centred on the major hospitals in the two counties and multiple sources of ascertainment were used. All identified cases had their case notes reviewed to establish the diagnosis and classify by type of MND. Point prevalence of MND was established for September 1st, 2007. The overall incidence rate standardised to the 2001 United Kingdom population was 2.52 per 100,000 (95% confidence interval 2.20–2.84). The incidence rate was significantly higher in males (P < 0.001). The estimated male to female incidence ratio was 2.10 (95% CI 1.61–2.73). The crude incidence rate in Cornwall was 3.78 per 100,000 (95% CI 3.03–4.53) and this was significantly higher (P = 0.011) than the rate in Devon, which was 2.61 per 100,000 (95% CI 2.19–3.04). The standardised incidence rate for the study period in Devon was 2.26 per 100,000 (95% CI 1.91–2.60) and in Cornwall it was 3.06 per 100,000 (95% CI 2.44–3.68). The overall standardised point prevalence rate was 5.66 per 100,000 (95% CI 4.49–6.83). The incidence rate of MND in our study is similar to reported findings in large prospective studies of the disease. There is a significant difference between the incidence rates in Devon and Cornwall. There is a need to establish a prospective MND Register to accurately document the epidemiological characteristics of the disease in the two counties.     

Trends in prevalence and incidence of multiple sclerosis in Bajo Aragón, Spain

OBJECTIVE: Recent reports provide consistent evidence that Spain is an area of high risk for multiple sclerosis (MS) according to prevalence surveys. However, the studies of incidence are scarce. The objective of the current work is to analyse whether the increased prevalence of MS is accompanied by increasing incidence in the area of Bajo Aragón, northeastern Spain. METHODS: The data of both prevalence and incidence were retrieved from a prospective register created in 1994 and which included patients with probable or definite MS. Crude and age-standardised rates were calculated from 1994 to 2002 and compared with those found retrospectively in the previous period of 1984-1993. RESULTS: In January 2003, we found a prevalence rate of 75/100,000 (95% CI: 52-97) whereas it was 35/100,000 (95% CI: 20-50) in 1994. In a period of 9 years, 25 new cases were diagnosed in the area with a mean annual incidence rate of 4.6/100,000 (95% CI: 2.8-6.5; range: 1.6-13.6) in comparison to 17 new cases from 1984 to 1993 with a mean incidence rate of 3/100,000 (95% CI: 1.6-4.5). The standardised ratio of incidences was 1.44 (95% CI: 0.95-2.17) and, therefore, the difference of rates was not significant. CONCLUSION: We conclude that the increase in prevalence of MS is more likely to be due to improvement on case ascertainment than to increasing incidence. Nonetheless, further prospective incidence studies in larger populations are warranted in Spain to elucidate whether the frequency of this disease is truly increasing.     

Frequency of multiple sclerosis in Menorca, Balearic islands, Spain

OBJECTIVE: To establish prevalence and incidence of multiple sclerosis (MS) in Menorca (Balearic Islands, Spain; population: 67,009). METHODS: An extensive epidemiological study was undertaken using all available information sources. Patients were classified according to Poser's criteria. RESULTS: The prevalence rate of definite and probable MS was 68.6/100,000 (95% confidence interval 50.3-91.6). The incidence rate was 3.4/100,000/year (95% CI 2.2-5.3). The time lag between the first symptom and diagnosis was 10.2 years for patients with disease onset before 1987 and 2.1 years for patients with onset between 1987 and 1996. CONCLUSION: Menorca's population has a moderately high MS risk, with a prevalence rate the highest reported for a Spanish region.     

Prevalence and incidence of multiple sclerosis in Las Palmas, Canary Islands, Spain

OBJECTIVES: To determine the prevalence and incidence of multiple sclerosis (MS) in the city of Las Palmas (Canary Islands, Spain), geographically belonging to north-western Africa, but with European ancestry. METHODS: This population-based survey was conducted for a period of 5 years (1998-2002) in a Sanitary District of Las Palmas city (28 degrees 20' N), with a population of 82,623 inhabitants. Multiple sources were periodically investigated for case ascertainment. Patients with definite and probable MS were included. RESULTS: Sixty-four patients with MS were identified on prevalence day, December 31, 2002. According to Poser's criteria the crude prevalence rate was 77.5 per 100,000 (95% CI: 59.7-98.9). This rate decreased to 73.8 (95% CI: 56.5-94.8) according to McDonald's criteria. Age-adjusted rates for the world and European standard populations were 61.6 (95% CI: 47.1-78.9) and 70.6 (95% CI: 55-89), respectively. Prevalence was higher for women aged 25-44 years. In 17 patients onset of MS occurred within the study period. Average annual incidence was 4.1 per 100,000 (95% CI: 2.4-6.6). CONCLUSIONS: The prevalence and incidence rates in Las Palmas city are close to those reported from Continental Spain and other countries of southern Europe with similar social and ethnic background. These results highlight the role of racial-ethnic factors in the genesis of MS.     

Factors in the rising prevalence of multiple sclerosis in the north-east of Ireland

BACKGROUND: Northern Ireland is recognized as an area of high risk for multiple sclerosis. The original study of Allison and Millar in 1951 found a prevalence of 51/100,000 and mean annual incidence of 2.74/100,000/year. Subsequent studies in 1961, 1986, and 1996 suggested rising prevalence--80, 138, and 168.2/100,000, respectively. METHODS: In 2004, we surveyed the North-East of Northern Ireland (population 160,446, area 2030 km(2)) using multiple sources of case ascertainment, all satisfying the Poser criteria for definite or probable multiple sclerosis (MS) or the McDonald criteria. RESULTS: From a provisional list of 469 cases, 370 (123 males, 247 females) were identified. The prevalence was 230.6 per 100,000 (95% CI 207.0-255.4) with significantly higher prevalence in females (300.8/100,000) than males (157.0/100,000). Direct standardization to the 1961 Northern Ireland population reduced the overall prevalence rate to 200.5/100,000 (95% CI 193.2-208.0), in females to 270.2/100,000 (95% CI 258.8-282.4) and in males to 131.1/100,000 (95% CI 122.8-139.9). In 1996, incidence had risen to 9.3/100,000/year (14 cases in population of 151,000) with a higher incidence in females (10.3/100,000/year) than males (8.3/100,000/year). CONCLUSIONS: Northern Ireland continues to have a rising prevalence of MS. The increase in incidence suggests a true increase in the disease.     

High incidence and prevalence of multiple sclerosis in south east Scotland: evidence of a genetic predisposition

OBJECTIVE—To determine the incidence andprevalence of multiple sclerosis in the Lothian and Border Health BoardRegions of south east Scotland.
METHODS—Incidence study: all patients wereidentified in whom a diagnosis of Poser category probable or definitemultiple sclerosis was made by a neurologist between 1992 and 1995. Prevalence study: all patients known to have multiple sclerosis whowere alive and resident in the study area on 15 March 1995 were recorded.
RESULTS—The crude annual incidence rates ofprobable or definite multiple sclerosis per 100 000 population were thehighest ever reported: 12.2 (95% confidence interval (95% CI)10.8-13.7) in the Lothian Region and 10.1 (95% CI 6.6-13.6) in theBorder Region. A total of 1613 patients with multiple sclerosis wereresident in the study area, giving standardised prevalence rates per100 000 population of 203 (95% CI 192-214) in the Lothian Region and219 (95% CI 191-251) in the Border Region. Prevalent cases were morelikely than expected to have a Scottish surname (risk ratio 1.24, 95% CI 1.14-1.34).
CONCLUSIONS—Orkney and Shetland were previouslythought to have by far the highest prevalence of multiple sclerosis inthe world: about double that found in England and Wales. However, theprevalence in south east Scotland is equally high, suggesting that theScottish population as a whole has a genetic susceptibility to thedisease, and undermining the hypothesis that patterns of infectionspecific to small sparsely populated island communities are importantin the causation of multiple sclerosis.

     

Prevalence of multiple sclerosis in Bogotá, Colombia

Among Latin American countries, Colombia is considered a low-risk area for multiple sclerosis (MS) and no studies on MS prevalence have been conducted in any of the country's large urban settings. To fill this gap and assess the prevalence of MS in Bogotá as of December 31, 2002, this study reviewed the clinical records of patients diagnosed with MS in most Bogotá hospitals. This review produced a sample of 296 patients with an MS diagnosis whose reliability was verified by a neurologist with expertise in MS. The total prevalence rate identified for December 2002 was 4.41/100,000 inhabitants (95% CI 3.9-4.9), including a rate of 5.98/100,000 (95% CI 5.2-6.8) for women and 2.71/100,000 (95% CI 2.2-3.3) for men (differences measured at p < 0.001). The prevalence estimates for Bogotá, confirm the city's status as a low-risk area for MS.     

Prevalence of multiple sclerosis in the L'Aquila district, central Italy

OBJECTIVE: To estimate the prevalence of multiple sclerosis in the L'Aquila district, central Italy. METHODS: All available case sources were screened. Definite and probable cases of multiple sclerosis, classified according to the Poser criteria, were considered as prevalent cases. RESULTS: On the prevalence day, 31 December 1996, 158 patients (105 women and 53 men; ratio 2:1) affected by definite (n=131) or probable (n=27) multiple sclerosis were alive and resident in the L'Aquila district. Mean (SD) age was 38.4 (11.9) years (38.9 (11.7) years for women and 38.5 (12.3) years for men, p=0.9). The overall crude prevalence was 53.0/100 000 (95% confidence interval (95% CI)=45.4-62.0); 68.4/100 000 (95% CI=56. 5-82.8) in women, and 36.7/100 000 (95% CI=28.1-48.0) in men. The prevalence was similar (55.9/100 000) when standardised to the 1996 European population. Mean (SD) age at onset of multiple sclerosis was 29.4 (9.6) years and mean (SD) duration of the disease was 9.4 (7.4) years, without any significant difference between sexes. Mean age at onset was significantly higher in patients with the primary progressive than in those with the relapsing-remitting course (p=0. 0002, Scheffé's test). CONCLUSIONS: The prevalence found in the L'Aquila district gives support to the consideration of Italy as an area in which multiple sclerosis has been shown to have high prevalence at least in the populations that were surveyed recently.     

Latitudinal variation in the prevalence of multiple sclerosis in Ireland, an effect of genetic diversity

BACKGROUND: Northern Ireland has a high and rising prevalence rate of multiple sclerosis (MS). The most recent survey in 1996 found a rate of 168.7/100 000. Recorded prevalence rates for the south of Ireland, including County Wexford, have been markedly lower and seemed to suggest the existence of a prevalence gradient within the island. OBJECTIVES: To compare the prevalence of multiple sclerosis in Co. Wexford in the south east of Ireland and Co. Donegal in the north west, and to establish whether a variation in prevalence of MS exists within Ireland. METHODS: Patients were referred from multiple sources. Review of clinical case records and/or patient examination confirmed the diagnosis. RESULTS: In Co. Wexford, 126 patients were found to have clinically definite or probable multiple sclerosis with a prevalence rate of 120.7/100 000 (95% confidence intervals (CI) 100.6 to 143.8), which is similar to other areas of similar latitude within the British Isles. In Co. Donegal, 240 people had clinically definite or probable MS with a prevalence rate of 184.6/100 000 (95% CI 162.0 to 209.5). The difference in prevalence rates is statistically significant (Z = 3.94, p = <0.001). CONCLUSION: There is a latitudinal variation in the prevalence rate of MS between the north and the south of Ireland. The increased prevalence of MS seen in Co. Wexford is likely to represent better case ascertainment and improved diagnostic accuracy rather than an actual increase in prevalence. The north/south variation in prevalence may represent a variation in the genetic predisposition to MS between the background populations of the two counties.     

Epidemiology of multiple sclerosis in western Herzegovina

OBJECTIVES: To determine epidemiological rates of multiple sclerosis (MS) in western Herzegovina. PATIENTS AND METHODS: We analysed data from 81 MS patients (49 females, 32 males) on the prevalence day, 31 December 2003. Patient information was obtained from a search of all available medical records from the period 1994-2003 in the investigated area. RESULTS: Crude prevalence of MS was 27/100,000 (95% confidence interval (CI) 20-34). Prevalence was highest in the mountainous municipality of Posusje (56/100,000) and lowest in the coastal municipality of Neum (0 incidence). The annual incidence of MS was 1.6/100,000 (95% CI 0-3.3). The female/male ratio of MS was 1.5. The mean age of the patients on prevalence day was 40.0+/-11.6 years, and the mean age at disease onset was 31.0+/-7.1 years. Eight (10%) of the patients had a first-degree relative with MS. The primary progressive (PP) disease course was observed only in females. Visual symptoms were the initial symptom of MS in 6 (7%) of the patients. CONCLUSIONS: Western Herzegovina is an area of moderate risk for MS, and the distribution of MS in western Herzegovina is heterogeneous. PP-MS occurred only in females, and involvement of the visual pathways as the initial symptom of MS was low.     

Prevalence of Parkinson's disease in the L'Aquila district, central Italy

OBJECTIVE: We estimated the prevalence of Parkinson's disease (PD) in the L'Aquila district. METHODS: Cases of PD were identified screening all available case sources including general practitioners and antiparkinsonian drug-users by means of pharmacy records. Prevalence of PD was computed considering the prevalence day of December 31, 2001. RESULTS: On the prevalence day, 682 patients with PD were alive and residing in the L'Aquila district. A total of 354 patients were women and 328 men. The overall crude prevalence rate was 229.3/100,000 (95% CI 212.7-247.1), without any difference between men (227.4/100,000; 95% CI 200.0-257.5) and women (231.1/100,000; 95% CI 202.2-263.1). Prevalence rates increased with age in both sexes and were higher in urban (244.5/100,000; 95% CI 213.7-278.5) than in rural residents (214.7/100,000; 95% CI 189.0-242.9) (SRR = 1.7; 95% CI 1.3-2.1). CONCLUSIONS: The prevalence of PD in the L'Aquila district was within the range of prevalence rates found in our country and steeply increased with advancing age in both sexes.     

Prevalence of multiple sclerosis in Isfahan, Iran

BACKGROUND: The prevalence of multiple sclerosis (MS) shows considerable variability all over the world. According to Kurtzke, Iran is considered to have a low prevalence. OBJECTIVE: To estimate the period prevalence and risk factors of MS in Isfahan, central part of Iran. METHODS: A cross-sectional case register study conducted between 2004 and 2005. In the province of Isfahan, Iran, all patients known to have definite MS during 2004 and 2005, being alive and resident within Isfahan as well as being a member of the Isfahan MS Association were included in the study. Demographic and case-related information was recorded. 1,391 definite MS patients (308 men and 1,083 women) from the Isfahan MS Association, Iran, have been identified. The disease was confirmed using clinical information and MRI findings by a neurologist and radiologist. The patients were evaluated by interview and a questionnaire. Population data were obtained from the year 1999 Iran Census. The mean (SD) age of the participants was 32.5 (9.3) years with a mean (SD) duration of the disease of 6.4 (5.1) years for men and 6.9 (5.3) years for women. RESULTS: The period prevalence of MS was 35.5 per 100,000 [95% confidence interval (CI) 33.6-37.3] in a population of 3,923,255, with a higher rate in women than men [54.5 (95% CI: 51.1-57.8) for women and 14.9 (95% CI: 13.3-16.6) for men]. The female/male ratio was 3.6 (95% CI: 3.2-4.1). The direct age-adjusted period prevalence was 59.5 per 100,000 (95% CI: 44.8-75.2) for women and 17.0 per 100,000 (95% CI: 8.9-25.1) for men. MS rates were highest among 30- to 39-year-olds and decreased with increasing age. Sensory and visual disturbances were the most common initial presentations with a prevalence of 51.1% (95% CI: 48.4-53.7) and 47.0% (95% CI: 44.4-49.7), respectively. CONCLUSION: Isfahan could be considered as an area with a medium to high risk of MS. This is in sharp contrast with the gradient hypothesis.     

Estimating the prevalence and incidence of multiple sclerosis in the Lorraine region, France, by the capture-recapture method

OBJECTIVE: The objective of this study was to assess the prevalence and incidence of multiple sclerosis (MS) in the Lorraine region, in France. METHODS: Data from three sources - Regional Health Insurance System, medical records departments and the Lorraine registry of MS - and a capture-recapture method with log-linear models were used to estimate the prevalence and incidence of MS. RESULTS: We identified 7193 records of reported MS corresponding to 4299 unique suspected cases of MS existing on 31 December 2008, in Lorraine. On the basis of the 4001 validated cases, the observed crude prevalence of MS was 170.9 cases per 100,000 inhabitants (95% confidence interval [CI]: 165.7; 176.3), and the observed annual crude incidence of MS was 4.4 cases per 100,000 inhabitants (95% CI: 3.6; 5.4). With the capture-recapture method, the estimated prevalence of MS was 4405.7 (95% CI: 4261.5; 4629.7), so an estimated 405 cases were not identified by the three sources. The estimated prevalence was 188.2 cases per 100,000 inhabitants (95% CI: 182.7; 193.8), and the estimated annual incidence was 8.5 cases per 100,000 inhabitants (95% CI: 7.3; 9.7). CONCLUSIONS: The capture-recapture method allowed us to estimate an additional 10.1% of unobserved prevalent cases and to anticipate 47.5% of unobserved incident cases.     

Prevalence and mortality of patients with multiple sclerosis in France in 2012: a study based on French health insurance data

Data on the prevalence of multiple sclerosis (MS) in France are scarce. National and regional updated estimates are needed to better plan health policies. In this nationwide study, we provided estimates of the prevalence of MS in France in 2012 and mortality rate in 2013. MS cases were identified in the French national health insurance database (SNIIRAM-PMSI) using reimbursement data for disease-modifying treatment, long-term disease status for MS, disability pension for MS, and hospitalisation for MS (MS ICD-10 code: G35). We identified 99,123 MS cases, corresponding to an overall crude prevalence rate of 151.2 per 100,000 inhabitants [95% confidence interval (CI) 150.3–152.2]: 210.0 per 100,000 in women (95% CI 208.4–211.5) and 88.7 per 100,000 in men (95% CI 87.6–89.7). The overall prevalence rate was 155.6 per 100,000 inhabitants (95% CI 154.7–156.6) after standardization on the 2013-European population. We observed a prevalence gradient with a higher prevalence (190–200 per 100,000) in North-Eastern France and a lower prevalence in Southern and Western France (126–140). The crude mortality rate in 2013 was 13.7 per 1,000 MS cases (11.4 in women and 20.3 in men). The standardized mortality ratio was 2.56 (95% CI 2.41–2.72). Our results revise upwards the estimation of MS prevalence in France and confirm the excess mortality of MS patients compared to the general population.     

Prevalence of multiple sclerosis in the province of Teruel, Spain

There have been few reports about the frequency of multiple sclerosis (MS) in Spain. We undertook a prevalence study in the province of Teruel, which is served by two hospitals as referral centres for a population of 143,680. We found a total of 46 patients who fulfilled Poser’s criteria for clinically definite or probable MS with a prevalence rate of 32/100,000 [95% confidence interval (CI): 22.8–41.3]. The prevalence rates for males and females were 23.5 (95% CI: 12.3– 34.7) and 40.6 (95% CI: 25.8–55.4) respectively. We found an incidence rate of 2.2/year per 100,000 in the last 5 years. The sex ratio (females/ males) was 1.7. The mean age on prevalence day was 40.6 years (range: 15–76). The clinical course was relapsing-remitting in 82% of patients, progressive in 9% and secondary progressive in the other 9%. The mean EDSS score was 3.73 (range: 1–8.5). Our results confirm the hypothesis that Spain is an area at high risk for MS. Received: 7 May 1996 Received in revised form: 17 September 1996 Accepted: 23 September 1996     

A prospective study of the incidence, prevalence and mortality of multiple sclerosis in Leeds

Objective: To establish the prospective incidence of multiple sclerosis and mortality rates of people with multiple sclerosis in Leeds Health Authority and an updated prevalence of multiple sclerosis on 31 October 1999. Methods A population based prevalence register established on 30 April 1996 was maintained by prospectively registering all new cases of multiple sclerosis, flagging all cases with the National Health Service Central Register for notification of deaths and by registering all new clinical events. General practitioners notified patients with multiple sclerosis moving into or out of the area. Results 136 incident cases were prospectively registered from 30 April 1996 living in Leeds Health Authority (with an estimated resident population of 728 840). 57 deaths were notified. 792 people with multiple sclerosis were identified living in Leeds on 31 October 1999. The mean annual incidence rate for the three-year period 1996–1998 was 6.1/10⁵ (95 % CI: 5.1–7.2). The sex ratio of incident cases was 2.3 to 1 women to men. On 31 October 1999 the prevalence of multiple sclerosis in the Leeds Health Authority was 108.7/10⁵ (95 % CI: 101.2–116.5). This compares with a prevalence of 97.3/10⁵ (95 % CI: 90.3 –104.7) on 30 April 1996. The prevalence of definite and probable multiple sclerosis was 93.3/10⁵ (95 % CI: 86.4–100.6) and of suspected multiple sclerosis was 15.4/10⁵ (95 % CI 12.7 –18.5). Crude annual mortality rates of people with multiple sclerosis for 1997 and 1998 were 1.9/10⁵ (95 % CI: 1.1 to 3.2) and 3.2/10⁵ (95 % CI: 2.0 to 4.7). Multiple sclerosis was noted as the underlying cause of death in 8 (14 %) cases. Conclusion The incidence of multiple sclerosis in the Leeds Health Authority is similar to that in the south of the United Kingdom. The difference in successive prevalence figures is less than that published in other serial studies. Multiple sclerosis was notified as the underlying cause of death in a minority of deaths in people with multiple sclerosis. Received: 5 December 2000, Received in revised form: 23 March 2001, Accepted: 10 July 2001     

Multiple sclerosis in Móstoles,central Spain

Objectives– Until relatively recently southern Europe was regarded as having a medium to low multiple sclerosis prevalence, of about 20 or less per 100,000. However, recent studies in Sardinia, Sicily, continental Italy, Cyprus and Spain have yielded higher MS prevalence rates, between 32 and 102.6 per 100,000. We present the results of a prevalence study of MS in the municipality of Móstoles, central Spain. Material and methods– To ascertain the prevalence of multiple sclerosis in Móstoles (195,979 inhabitants), an intensive study was undertaken using several sources of information. We used the Poser criteria in diagnosis. Results– There were 85 patients (53 women and 32 men) classified as definite or probable, prevalence 43.4/100,000 (95% CI, 34.7 to 53.7). The incidence rate was 3.8/100,000/year (95% CI, 2.7 to 5.3) in the last 5 years. Mean age on prevalence day was 38.8±10.9 years. Mean age at onset was 31.7±9.3 years. Mean interval between initial symptoms and diagnosis was 1.7 years. Mean duration of disease was 7.6±6.1 years. Overall, 70.6% had a relapsing–remitting course, 18.8% had a primary progressive and 10.5% had a secondary progressive. Mean EDSS score was 2.7±1.9. Conclusion– The Móstoles study confirms the conclusions of previous smaller population studies that Spain is a moderately high or medium MS risk zone.     

Increasing incidence of multiple sclerosis among women in Lorraine, Eastern France

This study aims to describe the prevalence and incidence rates of multiple sclerosis (MS) in Lorraine, France, and its secular trend from 1990 to 2002. Cases were sourced from the regional network of MS healthcare workers in the Lorraine region and include all cases with definite or probable MS according to Poser's criteria. We identified 2718 patients with MS on 31 December 2004. The prevalence rate was 120/100,000 (95% confidence interval [CI]: 119-121). Between 1990 and 2002, the average age- and sex-adjusted annual incidence rate was 5.5/100,000 (95% CI: 4.4-6.6). During this same period, there was a significant increase in overall incidence in women but not in men. The mean age at MS onset, disability score five years after onset, number of relapses during the first five years, and proportion of first attack with sequelae or polysymptomatic symptoms were not significantly different between each annual cohort during the study period. The prevalence and incidence rates of MS we found in our study were higher than in previous studies in France. The increase in incidence of MS between 1990 and 2002, mostly in women, was not related to better ascertainment of patients with mild disability.     

A prevalence survey of multiple sclerosis in Sussex.

A first survey of the Brighton and Mid-Downs health districts in Sussex showed a prevalence of multiple sclerosis of 111 per 100,000 (95% confidence interval (95% CI) 103-120) in a population of 596,594 on prevalence day, 1 July 1991. Cases were notified by multiple sources and to maximise case notification patients were not contacted. Cases were classified by hospital and family practitioner notes. The Poser criteria were used for classification. These criteria are precise and exclude cases of isolated spinal cord syndrome. The Allison and Millar criteria used in the surveys in Scotland may lack specificity and it is concluded that the high prevalence of multiple sclerosis in Scotland needs to be reassessed with the more precise criteria. Until this is done, the latitude effect within the United Kingdom remains not proved.