Increasing frequency of multiple sclerosis in Padova, Italy: a 30 year epidemiological survey

Adherence, Persistence, Switching and Costs of Injectable and Oral Therapies for Multiple Sclerosis. Real Life Analysis Over 6 Years of Treatment

Background: Adherence and persistence to treatment with disease-modifying therapies (DMTs) is a predictor of the efficacy of treatment. Aims: The objectives of the study were the analysis of adherence, persistence, switches, and costs of the drugs used in MS. Methods: This is a retrospective non-interventional pharmacological observational study of 610 patients diagnosed with Relapsing-Remitting Multiple Sclerosis (RRMS) under therapy between January 2007 and September 2022. Results: Adherence values were greater than 0.75 for all the drugs in considered for the study. The mean persistence value was 2.5 years on the analysis performed on the first-line treatment. Conclusion: In a therapy in which adherence is predominant, but not exclusive to therapy efficacy, persistence to the drug is synonymous with drug efficacy.

Multiple sclerosis epidemiological trends in Italy highlight the environmental risk factors

Italy is definitely a high-risk country for multiple sclerosis (MS). Over the last 50 years, several epidemiological studies, including longitudinal surveys, have disclosed that MS incidence and prevalence in Italy mainland and Islands (Sardinia and Sicily) have progressively increased, picturing a semi-parabolic curve. Based on the comprehensive scrutiny of 58 papers, we conclude that the latitude risk gradient does not fit to the Italian map of MS. The genetic heterogeneity of the Italian ethnicities, that likely forms the basis of MS predisposition, does not account for the dramatic increase of MS incidence and prevalence observed in Italy over the last half century that, rather, seems better explained by the effect of environmental factors.

Age and sex adjusted prevalence and annual incidence of multiple sclerosis in East-Azerbaijan, Iran

BACKGROUND

Incidence and prevalence of multiple sclerosis (MS) is postulated to be rising in recent decades. Therefore, updating and completing the information of patients is essential, especially in high population areas. East-Azerbaijan is the largest and most populous province in the northwest of Iran. This study aimed to determine the prevalence and annual incidence of MS from 2008 to 2017 in East-Azerbaijan.

METHODS

We evaluated the data of all patients who had registered at the MS center in the university hospital. The data include nearly all MS patients in the East-Azerbaijan region, because it is the only referral site in the area. All of the reported rates were calculated in 100,000 of the total population.

RESULTS

By the end of 2017, the number of MS patients was 2995 (residing in the, with 769 (25.67%) men and 2226 (74.32%) women. The prevalence rate was 75.72/100,000 (95 % CI: 73.06-78.48), 38.2 in men (95% CI: 35.5-41.0), and 114.61 for women (95% CI: 109.9-119.4), with a female to male (F/M) ratio of 3:1. The mean annual incidence rate was 7.63/100,000 (95% CI: 5.6-9.3), and this rate was higher in women than men. During the nine years, the incidence rate increased. The patients' mean age was 32.33 ± 8.92, with a peak prevalence in 25-29 years for both genders. In this study, 13.9% of patients had a positive MS family history.

CONCLUSIONS

This study showed a high prevalence of MS in the region. There is a significant increase in the incidence of MS during the nine years in East-Azerbaijan. The increment of incidence was more prominent in women. Also, considering the increasing incidence rate, it is concluded that the risk of MS is increasing in this region.

PM2.5 levels strongly associate with multiple sclerosis prevalence in the Province of Padua, Veneto Region, North-East Italy

Background:

Incidence and prevalence trends of multiple sclerosis (MS) in the Province of Padua, North-East Italy, suggest that environmental factors may be associated with increased MS risk.

Objective:

To investigate the association of PM2.5 with MS prevalence in one of the most polluted geographical area of Italy.

Methods:

In total, 1435 Italian MS patients residing in the Province of Padua were enrolled. The province surface was classified into urban areas, isolated villages, industrialized places, and countryside. Satellite-derived dust-free and sea salt-free PM2.5 concentrations (annual average 1998–2015, μg/m3) allowed the identification of 18 classes of territorial sections with statistically evaluable numbers of inhabitants. Possible correlations between residential locality types, PM2.5 concentrations, and MS prevalence were investigated.

Results:

MS prevalence was significantly ( p < 0.0001) higher in urban areas (ranging from 219 in Padua City to 169/100,000 in other urban areas) compared to isolated villages (116/100,000) or rural domains (109/100,000) and strongly correlated with the annual average concentration of PM2.5 ( r = 0.81, p < 0.001). Regression analysis further associated MS cases with PM.2.5 average concentration ( β = 0.11, p < 0.001).

Conclusion:

In the Province of Padua, MS prevalence is strongly associated with PM2.5 exposure suggesting that air pollutants may be one of the possible environmental risk factors for MS.

The nature of genetic susceptibility to multiple sclerosis: constraining the possibilities

BACKGROUND

Epidemiological observations regarding certain population-wide parameters (e.g., disease-prevalence, recurrence-risk in relatives, gender predilections, and the distribution of common genetic-variants) place important constraints on the possibilities for the genetic-basis underlying susceptibility to multiple sclerosis (MS).

METHODS

Using very broad range-estimates for the different population-wide epidemiological parameters, a mathematical model can help elucidate the nature and the magnitude of these constraints.

RESULTS

For MS no more than 8.5 % of the population can possibly be in the "genetically-susceptible" subset (defined as having a life-time MS-probability at least as high as the overall population average). Indeed, the expected MS-probability for this subset is more than 12 times that for every other person of the population who is not in this subset. Moreover, provided that those genetically susceptible persons (genotypes), who carry the well-established MS susceptibility allele (DRB1*1501), are equally or more likely to get MS than those susceptible persons, who don't carry this allele, then at least 84 % of MS-cases must come from this "genetically susceptible" subset. Finally, because men, compared to women, are at least as likely (and possibly more likely) to be susceptible, it can be demonstrated that women are more responsive to the environmental factors that are involved in MS-pathogenesis (whatever these are) and, thus, susceptible women are more likely actually to develop MS than susceptible men. Finally, in contrast to genetic susceptibility, more than 70 % of men (and likely also women) must have an environmental experience (including all of the necessary factors), which is sufficient to produce MS in a susceptible individual.

CONCLUSIONS

As a result, because of these constraints, it is possible to distinguish two classes of persons, indicating either that MS can be caused by two fundamentally different pathophysiological mechanisms or that the large majority of the population is at no risk of the developing this disease regardless of their environmental experience. Moreover, although environmental-factors would play a critical role in both mechanisms (if both exist), there is no reason to expect that these factors are the same (or even similar) between the two.

The epidemiology of multiple sclerosis: insights to a causal cascade

MS-pathogenesis involves both genetic-susceptibility and environmental determinants. Three (or more) sequential environmental-factors are implicated. The first acts near birth, the second acts during childhood/adolescence, and the third acts subsequently. Two candidate factors (vitamin D deficiency and Epstein-Barr viral infection) seem particularly well-suited to the first two environmental-events but other factors (e.g., obesity and smoking behavior) seem also to be involved in the causal scheme. MS-pathogenesis can be modeled by incorporating both the environmental and genetic-factors into a causal scheme, which can then help to explain some of the changes in MS-epidemiology (e.g., increasing disease-prevalence, changing sex-ratio, and regional-variations in monozygotic-twin-concordance-rates), which have been taking place recently. This model suggests that genetic-susceptibility is overwhelmingly the most important determinant of MS and that, at least, 92.5% of individuals (and likely much more) are, essentially, incapable of developing MS, regardless of their specific environmental-exposures. Nevertheless, the genetics is complex and the contribution of any specific gene to MS-susceptibility seems to be quite modest. Thus, even for the DRB1*1501 allele (the strongest known MS-susceptibility marker), most carriers are not in the genetically-susceptible group. Moreover, 45-50% of individuals with MS lack this allele entirely and some of the haplotypes that carry this allele don't also confer any disease-risk. Finally, because the prevalence of genetic-susceptibility seems to be so similar throughout North America and Europe, and despite the crucial importance of a person's genetic make-up to disease pathogenesis, it is the environmental-factors, which largely responsible for the observed regional variations in disease-characteristics. Thus, despite MS being more common in women, men are more likely to be genetically-susceptible. This apparent paradox seems to relate to the fact that women are much more responsive than men to the recent changes in environmental-exposure (whatever these have been). These gender-differences may help to explain changes in the sex-ratio and the increasing disease-prevalence, which have both been observed recently. The potential importance of these conclusions regarding the role of environment in MS-pathogenesis is that they open the door to the possibility of pursuing strategies for primary primary disease prevention in the future.

Onset-adjusted incidence of multiple sclerosis in the Girona province (Spain): Evidence of increasing risk in the south of Europe

BACKGROUND

Recent studies show an increasing incidence of multiple sclerosis (MS) in southern Europe. Although by its geographical location and genetic characteristics Spain is expected to be similar to other southern European regions, data on incidence are scarce. The aim of this study was to determine the onset-adjusted incidence of MS in the Girona province in Catalonia (Spain).

METHODS

A prospective incidence study pooling data from the population-based Catalonia MS Registry was performed. Incident cases were defined as patients who had the onset of symptoms compatible with a clinically isolated syndrome (CIS) suggestive of MS in 2009 and fulfilled McDonald-2005 criteria during follow-up. Age- and sex-specific incidence rates were obtained.

RESULTS

The Registry included 182 patients residing in Girona that presented a CIS from January 2009 to December 2013. Fifty one patients had the onset of symptoms in 2009, of whom 27 patients fulfilled the diagnostic criteria, giving an incidence of 3.6 per 100,000 (CI 95% 2.4-5.3) inhabitants; 4.3 (CI 95% 2.5-7.1) for women and 2.9 (CI 95% 1.4-5.2) for men. The age-adjusted incidence rate for the European population was 3.29 (CI 95% 3.2-3.3).

CONCLUSION

The incidence estimation derived in this study is consistent with recent epidemiological data of MS in southern Europe suggesting an increase in incidence in this region.

Multiple sclerosis and seizures: incidence and prevalence over 40 years

OBJECTIVES

The prevalence of multiple sclerosis (MS) is increasing worldwide. Epileptic seizures are more common in MS patients than in the general population. The aim of this study was to investigate changes in the prevalence and incidence of MS in a well-defined population over several decades and estimate the occurrence of epilepsy in the same cohort.

MATERIALS AND METHODS

Patients diagnosed with MS in the County of Vestfold, Norway in the period of 1983-2003 were identified. Point prevalence for MS and epilepsy was calculated for January 1, 2003. The average annual incidence rates were calculated in five-year periods from 1983 to 2002. These numbers were compared to previously published figures of prevalence from 1963 and incidence from 1953.

RESULTS

On prevalence day, we identified 364 patients diagnosed with MS living in Vestfold. Thus, the prevalence increased from 61.6/100,000 in 1963 to 166.8/100,000 in 2003. In the period 1983-2002, the annual incidence fluctuated between 4.2 and 7.3/100,000/year (mean 4.5, 95% CI 3.6 - 5.5). In 2003, the portion of MS patients with epileptic seizures was 7.4%, compared to 2.9% in 1963.

CONCLUSIONS

During the 40 years follow-up of this population, the incidence of MS was stable, while the prevalence of MS and the share of MS patients with epileptic seizures increased. Compared to the general population, the risk of having active epilepsy was increased fourfold. We assume that this is a consequence of an increased survival in MS patients.

The epidemiology of multiple sclerosis: insights to disease pathogenesis

The purpose of studying the epidemiology of multiple sclerosis (MS) is twofold. First, it is important to understand clearly the natural history of the illness in order to assist patients in making decisions about their future with respect to issues such as family planning, the importance of securing lifelong healthcare, their ability to get and maintain employment, and making appropriate choices of therapy for their particular circumstances. This is not to suggest that, even with the best possible information, the ultimate prognosis for any individual can be predicted with absolute accuracy. It cannot. Nevertheless, accurate information can be very helpful both to reassure patients that many individuals with MS do remarkably well in the long term (perhaps, especially, with current and future therapies) and also to empower individuals with respect to their ability to make their own life choices. Second, and arguably the more important purpose for studying the epidemiology of MS, is to gain insights to the underlying causes of the disease. Indeed, if the principal mechanisms of disease pathogenesis were to be understood clearly, then it might be possible to entertain notions of either a cure for existing disease or the primary prevention of future disease. Much of our current understanding of disease pathogenesis, as discussed in other chapters of this volume, has been derived from basic science investigations of animal models of MS such as experimental autoimmune encephalomyelitis (EAE), and these models have provided considerable insight both to the complexity of the mammalian immune system and to the mechanisms underlying its dysfunction in inflammatory autoimmune conditions. Nevertheless, MS is a disease of humans without any known, naturally occurring, counterpart in any nonhuman species. For this reason, the clues to disease pathogenesis provided by a study of basic epidemiologic facts regarding MS (and by a systematic consideration of their implications) are essential to a comprehensive understanding of the human illness we call MS.

Multiple Sclerosis in the Mount Etna region: possible role of volcanogenic trace elements

BACKGROUND

Trace elements have been hypothesised to be involved in the pathogenesis of Multiple Sclerosis and volcanic degassing is the major natural sources of trace elements. Both incidence of Multiple Sclerosis in Catania and volcanic activity of Mount Etna have been significantly increased during the last 30 years. Due to prevailing trade winds direction, volcanic gases from Etna summit craters are mostly blown towards the eastern and southern sectors of the volcano.

OBJECTIVE

To evaluate the possible association between Multiple Sclerosis and exposure to volcanogenic trace elements.

METHODS

We evaluated prevalence and incidence of Multiple Sclerosis in four communities (47,234 inhabitants) located in the eastern flank and in two communities (52,210 inhabitants) located in the western flank of Mount Etna, respectively the most and least exposed area to crater gas emissions.

RESULTS

A higher prevalence was found in the population of the eastern flank compared to the population of the western one (137.6/100,000 versus 94.3/100,000; p-value 0.04). We found a borderline significantly higher incidence risk during the incidence study period (1980-2009) in the population of the eastern flank 4.6/100,000 (95% CI 3.1-5.9), compared with the western population 3.2/100,000 (95% CI 2.4-4.2) with a RR of 1.41 (95% CI 0.97-2.05; p-value 0.06). Incidence risks have increased over the time in both populations reaching a peak of 6.4/100,000 in the eastern flank and of 4.4/100.000 in the western flank during 2000-2009.

CONCLUSION

We found a higher prevalence and incidence of Multiple Sclerosis among populations living in the eastern flank of Mount Etna. According to our data a possible role of TE cannot be ruled out as possible co-factor in the MS pathogenesis. However larger epidemiological study are needed to confirm this hypothesis.

Increased incidence of multiple sclerosis in the Veneto region, Italy

BACKGROUND

To what extent the progressive increase in the incidence of multiple sclerosis (MS) observed in the province of Padova over the period 1970-1999 was an expression of a real increased risk of developing MS remained unclear.

OBJECTIVE

The objective of this paper is to update the epidemiological figures of MS and probe whether the risk of having MS has increased in the province of Padova during the decade 2000-2009.

METHODS

All patients born in Italy and having a diagnosis of MS or possible MS identified through analysis of all available sources of information were included in the study. The incidence and prevalence rates between 2000 and 2009 were obtained and compared with our previously published data.

RESULTS

On 31 December 2009, the overall prevalence was 139.5/100,000, 192.0 ± 9.5 for females and 83.9 ± 6.3 for males. During the decade 2000-2009, the overall incidence rate of MS was 5.5 ± 0.5, 7.4 ± 0.8 for females and 3.5 ± 0.6 for males. The onset-diagnosis delay, the female/male ratio and the mean age at onset did not significantly change compared to the prior period of observation.

CONCLUSION

Our findings support the hypothesis of a real increased risk of developing MS in the province of Padova. Moreover, the actual prevalence of 1.4/1000 makes our region a high-risk geographical area for MS. The role played by exogenous factors in determining susceptibility to MS needs to be thoroughly investigated.

Incidence and prevalence of multiple sclerosis in Europe: a systematic review

BACKGROUND

Multiple sclerosis (MS) is the most common cause of neurological disability in young adults worldwide and approximately half of those affected are in Europe. The assessment of differential incidence and prevalence across populations can reveal spatial, temporal and demographic patterns which are important for identifying genetic and environmental factors contributing to MS. However, study methodologies vary and the quality of the methods can influence the estimates. This study aimed to systematically review European studies of incidence and prevalence of MS and to provide a quantitative assessment of their methodological quality.

METHODS

A comprehensive literature search was performed to obtain all original population-based studies of MS incidence and prevalence in European populations conducted and published between January 1985 and January 2011. Only peer-reviewed full-text articles published in English or French were included. All abstracts were screened for eligibility and two trained reviewers abstracted the data and graded the quality of each study using a tool specifically designed for this study.

RESULTS

There were 123 studies that met the inclusion criteria. The study estimates were highly heterogeneous, even within regions or countries. Quality was generally higher in the more recent studies, which also tended to use current diagnostic criteria. Prevalence and incidence estimates tended to be higher in the more recent studies and were higher in the Nordic countries and in northern regions of the British Isles. With rare exceptions, prevalence and incidence estimates were higher in women with ratios as high as 3:1. Few studies examined ethnicity. Epidemiological data at the national level was uncommon and there were marked geographical disparities in available data, with large areas of Europe unrepresented and other regions well-represented in the literature. Only 37% of the studies provided standardized estimates.

CONCLUSIONS

Despite the breadth of the literature on the epidemiology of MS in Europe, inter-study comparisons are hampered by the lack of standardization. Further research should focus on regions not yet studied and the evaluation of ethnic differences in MS prevalence and incidence. National-level studies using current diagnostic criteria, validated case definitions and similar age- and sex-standardization would allow better geographical comparisons.

Infodemiology and infoveillance of multiple sclerosis in Italy

Multiple Sclerosis (MS) is a chronic debilitating disease of probable autoimmune inflammatory nature, whose aetiology is not fully understood, despite the many efforts and investigations. In this manuscript, we review the concept of “Multiple Sclerosis 2.0”, that is to say the Internet usage by MS patients, for seeking health and disease-related material for self-care and self-management purposes, and we introduce a Google Trends-based approach for monitoring MS-related Google queries and searches, called MS infodemiology and infoveillance. Google Trends has already proven to be reliable for infectious diseases monitoring, and here we extend its application and potentiality in the field of neurological disorders.

Incidence of multiple sclerosis among European Economic Area populations, 1985-2009: the framework for monitoring

Background

A debate surrounding multiple sclerosis epidemiology has centred on time-related incidence increases and the need of monitoring. The purpose of this study is to reassess multiple sclerosis incidence in the European Economic Area.

Methods

We conducted a systematic review of literature from 1965 onwards and integrated elements of original research, including requested or completed data by surveys authors and specific analyses.

Results

The review of 5323 documents yielded ten studies for age- and sex-specific analyses, and 21 studies for time-trend analysis of single data sets. After 1985, the incidence of multiple sclerosis ranged from 1.12 to 6.96 per 100,000 population, was higher in females, tripled with latitude, and doubled with study midpoint year. The north registered increasing trends from the 1960s and 1970s, with a historic drop in the Faroe Islands, and fairly stable data in the period 1980-2000; incidence rose in Italian and French populations in the period 1970-2000, in Evros (Greece) in the 1980s, and in the French West Indies in around 2000.

Conclusions

We conclude that the increase in multiple sclerosis incidence is only apparent, and that it is not specific to women. Monitoring of multiple sclerosis incidence might be appropriate for the European Economic Area.

Geomagnetic disturbances may be environmental risk factor for multiple sclerosis: an ecological study of 111 locations in 24 countries

BACKGROUND

We noticed that a hypothesis based on the effect of geomagnetic disturbances (GMD) has the ability to explain special features of multiple sclerosis (MS). Areas around geomagnetic 60 degree latitude (GM60L) experience the greatest amount of GMD. The easiest way to evaluate our hypothesis was to test the association of MS prevalence (MSP) with angular distance to geomagnetic 60 degree latitude (AMAG60) and compare it with the known association of MS with geographical latitude (GL). We did the same with angular distance to geographic 60 degree latitude (AGRAPH60) as a control.

METHODS

English written papers with MSP keywords, done in Europe (EUR), North America (NA) or Australasia (AUS) were retrieved from the PubMed. Geomagnetic coordinates were determined for each location and AMAG60 was calculated as absolute value of numerical difference between its geomagnetic latitude from GM60L. By an ecological study with using meta-regression analyses, the relationship of MSP with GL, AMAG60 and AGRAPH60 were evaluated separately. MSP data were weighted by square root of number of prevalent cases. Models were compared by their adjusted R square (AR2) and standard error of estimate (SEE).

RESULTS

111 MSP data were entered in the study. In each continent, AMAG60 had the best correlation with MSP, the largest AR2 (0.47, 0.42 and 0.84 for EUR, NA and AUS, respectively) and the least SEE. Merging both hemispheres data, AMAG60 explained 56% of MSP variations with the least SEE (R = 0.75, AR2 = 0.56, SEE = 57), while GL explained 17% (R = 0.41, AR2 = 0.17, SEE = 78.5) and AGRAPH60 explained 12% of that variations with the highest SEE (R = 0.35, AR2 = 0.12, SEE = 80.5).

CONCLUSIONS

Our results confirmed that AMAG60 is the best describer of MSP variations and has the strongest association with MSP distribution. They clarified that the well-known latitudinal gradient of MSP may be actually a gradient related to GM60L. Moreover, the location of GM60L can elucidate why MSP has parabolic and linear gradient in the north and south hemisphere, respectively. This preliminary evaluation supported that GMD can be the mysterious environmental risk factor for MS. We believe that this hypothesis deserves to be considered for further validation studies.

Cost of disorders of the brain in Europe 2010

BACKGROUND

The spectrum of disorders of the brain is large, covering hundreds of disorders that are listed in either the mental or neurological disorder chapters of the established international diagnostic classification systems. These disorders have a high prevalence as well as short- and long-term impairments and disabilities. Therefore they are an emotional, financial and social burden to the patients, their families and their social network. In a 2005 landmark study, we estimated for the first time the annual cost of 12 major groups of disorders of the brain in Europe and gave a conservative estimate of €386 billion for the year 2004. This estimate was limited in scope and conservative due to the lack of sufficiently comprehensive epidemiological and/or economic data on several important diagnostic groups. We are now in a position to substantially improve and revise the 2004 estimates. In the present report we cover 19 major groups of disorders, 7 more than previously, of an increased range of age groups and more cost items. We therefore present much improved cost estimates. Our revised estimates also now include the new EU member states, and hence a population of 514 million people.

AIMS

To estimate the number of persons with defined disorders of the brain in Europe in 2010, the total cost per person related to each disease in terms of direct and indirect costs, and an estimate of the total cost per disorder and country.

METHODS

The best available estimates of the prevalence and cost per person for 19 groups of disorders of the brain (covering well over 100 specific disorders) were identified via a systematic review of the published literature. Together with the twelve disorders included in 2004, the following range of mental and neurologic groups of disorders is covered: addictive disorders, affective disorders, anxiety disorders, brain tumor, childhood and adolescent disorders (developmental disorders), dementia, eating disorders, epilepsy, mental retardation, migraine, multiple sclerosis, neuromuscular disorders, Parkinson's disease, personality disorders, psychotic disorders, sleep disorders, somatoform disorders, stroke, and traumatic brain injury. Epidemiologic panels were charged to complete the literature review for each disorder in order to estimate the 12-month prevalence, and health economic panels were charged to estimate best cost-estimates. A cost model was developed to combine the epidemiologic and economic data and estimate the total cost of each disorder in each of 30 European countries (EU27+Iceland, Norway and Switzerland). The cost model was populated with national statistics from Eurostat to adjust all costs to 2010 values, converting all local currencies to Euro, imputing costs for countries where no data were available, and aggregating country estimates to purchasing power parity adjusted estimates for the total cost of disorders of the brain in Europe 2010.

RESULTS

The total cost of disorders of the brain was estimated at €798 billion in 2010. Direct costs constitute the majority of costs (37% direct healthcare costs and 23% direct non-medical costs) whereas the remaining 40% were indirect costs associated with patients' production losses. On average, the estimated cost per person with a disorder of the brain in Europe ranged between €285 for headache and €30,000 for neuromuscular disorders. The European per capita cost of disorders of the brain was €1550 on average but varied by country. The cost (in billion €PPP 2010) of the disorders of the brain included in this study was as follows: addiction: €65.7; anxiety disorders: €74.4; brain tumor: €5.2; child/adolescent disorders: €21.3; dementia: €105.2; eating disorders: €0.8; epilepsy: €13.8; headache: €43.5; mental retardation: €43.3; mood disorders: €113.4; multiple sclerosis: €14.6; neuromuscular disorders: €7.7; Parkinson's disease: €13.9; personality disorders: €27.3; psychotic disorders: €93.9; sleep disorders: €35.4; somatoform disorder: €21.2; stroke: €64.1; traumatic brain injury: €33.0. It should be noted that the revised estimate of those disorders included in the previous 2004 report constituted €477 billion, by and large confirming our previous study results after considering the inflation and population increase since 2004. Further, our results were consistent with administrative data on the health care expenditure in Europe, and comparable to previous studies on the cost of specific disorders in Europe. Our estimates were lower than comparable estimates from the US.

DISCUSSION

This study was based on the best currently available data in Europe and our model enabled extrapolation to countries where no data could be found. Still, the scarcity of data is an important source of uncertainty in our estimates and may imply over- or underestimations in some disorders and countries. Even though this review included many disorders, diagnoses, age groups and cost items that were omitted in 2004, there are still remaining disorders that could not be included due to limitations in the available data. We therefore consider our estimate of the total cost of the disorders of the brain in Europe to be conservative. In terms of the health economic burden outlined in this report, disorders of the brain likely constitute the number one economic challenge for European health care, now and in the future. Data presented in this report should be considered by all stakeholder groups, including policy makers, industry and patient advocacy groups, to reconsider the current science, research and public health agenda and define a coordinated plan of action of various levels to address the associated challenges.

RECOMMENDATIONS

Political action is required in light of the present high cost of disorders of the brain. Funding of brain research must be increased; care for patients with brain disorders as well as teaching at medical schools and other health related educations must be quantitatively and qualitatively improved, including psychological treatments. The current move of the pharmaceutical industry away from brain related indications must be halted and reversed. Continued research into the cost of the many disorders not included in the present study is warranted. It is essential that not only the EU but also the national governments forcefully support these initiatives.

Multiple sclerosis prevalence in Malaga, Southern Spain estimated by the capture–recapture method

Background: Although not definitively proven, there is commonly accepted to be a latitudinal gradient in the distribution of multiple sclerosis (MS), which is more frequent in temperate zones. The European Mediterranean countries are situated in a zone of median frequency, although ever increasing figures have been noted in the last decades.

Objective: The objective of this study was to assess the current prevalence rate of MS in the province of Malaga, Southern Spain.

Methods: The capture–recapture method (CRM) uses independent sources of data and permits the number of non-registered cases of a given disease to be estimated, and by doing so, to avoid ascertainment bias.

Results: Use of this method showed the estimated prevalence rate of MS in the province of Malaga, Southern Spain, to be 125/105 (95% confidence interval: 102/105–169/105), higher than the figures published previously.

Conclusions: Although we recognize that these data need to be confirmed in further studies and in other areas of the country using a similar method, we believe this study is the first to find such high figure of prevalence, being very similar to the figures reported in recent years in other southern European countries.

Multiple sclerosis in Italy: cost-of-illness study

This study estimates the direct costs of multiple sclerosis (MS) in Italy from the perspective of the National Health System. Patients diagnosed with MS for ≥1 year prior to study entry were included in the analysis; neurological disability was assessed using the Expanded Disability Status Scale (EDSS). Cost variables were analyzed according to: MS phenotype, disease course over the previous year and EDSS rating. A total of 510 patients were included in the analysis. Overall costs were significantly higher for relapsing-remitting MS and secondary progressive MS than for primary progressive MS (P < 0.05). Costs were higher for EDSS scores 0.0-3.5 and 4.0-6.0 than for scores > 6.0 (P < 0.05). The extrapolated data gave an estimated annual direct cost of MS per patient of <euro>18,030. In conclusion, relapsing-remitting MS or secondary progressive MS phenotypes and lower estimated EDSS scores appear to be associated with higher costs.

Increasing frequency of multiple sclerosis in Catania, Sicily: a 30-year survey

Background and Objective: The objective of this study was to determine the prevalence and incidence of multiple sclerosis (MS) and its temporal profiles from 1975 to 2005 in the city of Catania.

Methods: The incidence of MS from 1975 to 31 December 1999 had been previously investigated by the same group. The frequency of MS in the community of Catania from 1 January 2000 to 31 December 2004 was studied in a population of 313,110 inhabitants (2001 census). All patients who satisfied Poser’s criteria were considered as prevalent and incident cases.

Results: Three hundred and ninety-eight patients with MS who had experienced the clinical onset of the disease before 31 December 2004 were found in a population of 313,110 inhabitants. The prevalence rate was 127.1/100,000 [95% confidence interval (CI) 115.1–140.4]. From 2000 to 2004, 108 patients with MS had clinical onset of the disease . The mean annual incidence was 7.0/100,000 (95% CI 5.7–13.7) and was higher in women (8.4/100,000; 95% CI 6.4–10.5) than in men (5.3/100,000; 95% CI 3.7–7.2). The mean length of time between the date of clinical onset and the date of the diagnosis was 1.4 ± 1.7 years. During the last 30 years the incidence of MS in this population increased from 1.3/100,000 during the first quinquennium (1975–9) to 7.0/100,000 during 2000–4.

Conclusions: Incidence rates have further increased in this population, suggesting that the risk of MS is still increasing.

The prevalence of multiple sclerosis in central Italy

Background: The prevalence of multiple sclerosis varies considerably throughout the world.

Objective: To better define the prevalence of MS in central Italy.

Methods: This is a population-based study conducted in the province of Frosinone, which is situated in the Lazio region, central Italy. The selected prevalence day was 1 January 2007. A total of 467 patients, with a definite diagnosis of multiple sclerosis, were considered for crude, age- and sex-specific prevalence estimation.

Results: The overall crude prevalence rate was 95.0 cases per 100,000 (95% confidence interval (CI) 86.6—104.0). A significantly higher prevalence rate was recorded in females (134.9, 95% CI 121.0—150.1) than in males (53.3, 95% CI 44.4—63.3) ( p = 0.001). Age-specific prevalence peaked in the 25—34 year, 35—44 year and 45—54 year age groups; moreover, it was found to increase up to the 35—44 year age group in males and the 45—54 year age group in females, decreasing thereafter. The female to male ratio was 2.6.

Conclusions: The results confirm that MS occurs more frequently in central Italy than might be expected on the basis of the geographic-related distribution model, thus supporting the view that this is a high-risk area for the disease.

The changing demographic pattern of multiple sclerosis epidemiology

The uneven distribution of multiple sclerosis (MS) across populations can be attributed to differences in genes and the environment and their interaction. Prevalence and incidence surveys could be affected by inaccuracy of diagnosis and ascertainment, and prevalence also depends on survival. These sources of error might play a part in the geographical and temporal variations. Our literature search and meta-regression analyses indicated an almost universal increase in prevalence and incidence of MS over time; they challenge the well accepted theory of a latitudinal gradient of incidence of MS in Europe and North America, while this gradient is still apparent for Australia and New Zealand; and suggest a general, although not ubiquitous, increase in incidence of MS in females. The latter observation should prompt epidemiological studies to focus on changes in lifestyle in females. New insights into gene-environment and gene-gene interactions complicate interpretations of demographic epidemiology and have made obsolete the idea of simple causative associations between genes or the environment and MS.

Environmental factors and their timing in adult-onset multiple sclerosis

Multiple sclerosis (MS) is a common, complex neurological disease. Epidemiological data implicate both genetic and environmental factors in the etiology of MS, with various factors interacting with one another. Environmental exposures might occur long before the disease becomes clinically evident, as suggested by the wide range in onset age. In this Review, we examine the key time periods during which the environment might contribute to MS susceptibility, as well as the potential environmental factors involved. Understanding the nature of environmental influences in MS is highly relevant to the development of public health measures that are aimed at preventing this debilitating disease.

The causal cascade to multiple sclerosis: a model for MS pathogenesis

BACKGROUND

MS pathogenesis seems to involve both genetic susceptibility and environmental risk factors. Three sequential factors are implicated in the environmental risk. The first acts near birth, the second acts during childhood, and the third acts long thereafter. Two candidate factors (vitamin D deficiency and Epstein-Barr viral infection) seem well suited to the first two environmental events.

METHODOLOGY/PRINCIPAL FINDINGS

A mathematical Model for MS pathogenesis is developed, incorporating these environmental and genetic factors into a causal scheme that can explain some of the recent changes in MS-epidemiology (e.g., increasing disease prevalence, a changing sex-ratio, and regional variations in monozygotic twin concordance rates).

CONCLUSIONS/SIGNIFICANCE

This Model suggests that genetic susceptibility is overwhelmingly the most important determinant of MS pathogenesis. Indeed, over 99% of individuals seem genetically incapable of developing MS, regardless of what environmental exposures they experience. Nevertheless, the contribution of specific genes to MS-susceptibility seems only modest. Thus, despite HLA DRB1*1501 being the most consistently identified genetic marker of MS-susceptibility (being present in over 50% of northern MS patient populations), only about 1% of individuals with this allele are even genetically susceptible to getting MS. Moreover, because genetic susceptibility seems so similar throughout North America and Europe, environmental differences principally determine the regional variations in disease characteristics. Additionally, despite 75% of MS-patients being women, men are 60% more likely to be genetically-susceptible than women. Also, men develop MS at lower levels of environmental exposure than women. Nevertheless, women are more responsive to the recent changes in environmental-exposure (whatever these have been). This explains both the changing sex-ratio and the increasing disease prevalence (which has increased by a minimum of 32% in Canada over the past 35 years). As noted, environmental risk seems to result from three sequential components of environmental exposure. The potential importance of this Model for MS pathogenesis is that, if correct, a therapeutic strategy, designed to interrupt one or more of these sequential factors, has the potential to markedly reduce or eliminate disease prevalence in the future.

Clinical and diagnostic aspects of multiple sclerosis and acute monophasic encephalomyelitis in pediatric patients: a single centre prospective study

OBJECTIVE

The purpose of the study was to compare and contrast the initial presenting demographic, clinical, neuroimaging, and laboratory features in a cohort of children affected from multiple sclerosis (MS) or acute disseminated encephalomyelitis (ADEM).

METHODS

A 12-year prospective study was conducted in 68 pediatric patients (age<or=17 years) who presented with a first episode of central nervous system inflammation suggestive of a demyelinating multifocal pathology. All patients had undergone magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) examination. The mean follow-up period, as at ending on December 31, 2007, was 6.8+/-2.7 years (range 3.2-12.6 years).

RESULTS

At clinical onset, children who developed MS during the follow-up (48 patients; 34 females, 14 males; mean age at onset: 14.4+/-2.5) significantly differed from children affected by ADEM (20 patients; 8 females, 12 males; mean age at onset: 8.1+/-3.8) for the following parameters: prevalence of females affected (female/male ratio: 2.8 versus 0.6, P=0.03); mean age at onset (P<0.001); monosymptomatic onset (73% vs 30%, P=0.002); encephalopathy-like onset (0% vs 50%, P<0.001); presence of oligoclonal IgG bands (IgGOB) in CSF (83% vs 10%, P<0.001); and periventricular (79% vs 20%, P<0.001), brain stem (12.5% vs 60%, P=0.000), and basal ganglia (10% vs 50%, P<0.001) lesions at MRI.

CONCLUSIONS

Our findings depict a pattern of demographic, clinical, neuroimaging, and laboratory findings that can help to distinguish, at clinical onset, children suffering from ADEM from those who will develop MS. Childhood-onset MS seems not to differ from adult-onset MS from both clinical and paraclinical features.

Extensive cortical inflammation is associated with epilepsy in multiple sclerosis

INTRODUCTION

Epilepsy is three to six times more frequent in MS than in the general population. Previous studies based on conventional magnetic resonance (MR) imaging have suggested a possible correlation between cortical inflammatory pathology and epileptic seizures. However, pure intracortical lesions (ICLs) are unlikely to be demonstrated with conventional MR. We applied the double inversion recovery (DIR) sequence in relapsing remitting MS (RRMS) patients with or without epileptic seizures in order to clarify the relationship between ICLs and epilepsy in MS in vivo.

METHODS

Twenty RRMS patients who had epileptic seizures (RRMS/E) during the course of the disease were studied for the presence of ICLs. A group of 80 RRMS patients with no history of seizures and matched for gender, age, disease duration, Expanded Disability Status Scale (EDSS) grading, and T2 lesion volume (T2-WMLV) was selected as reference population. ICLs were detected by applying the DIR sequence.

RESULTS

ICLs were observed in 18/20 (90%) RRMS/E and in 39/80 (48%) RRMS (p = 0.001). RRMS/E showed five times more ICLs (7.2 +/- 8.4) than RRMS (1.5 +/- 2.4; p = 0.015). The total ICLs volume was 6 times larger in RRMS/E than in RRMS (1.2 +/- 1.7 cm3 versus 0.2 +/- 0.2 cm3, p = 0.016). No significant difference was observed between RRMS and RRMS/E with regard to the number and volume of juxtacortical lesions and T2-WMLV.

DISCUSSION

Our findings indicate that RRMS/E have more extensive cortical inflammation than RRMS patients with no history of epilepsy. Inflammatory ICLs may be responsible for epilepsy in MS.

Multiple sclerosis in the Republic of San Marino: a prevalence and incidence study

Studies on the distribution of multiple sclerosis (MS) carried out in Southern Europe in the last years have shown a significant increase in the frequency of the disease. A previous descriptive survey in the Republic of San Marino, northern Italian peninsula, published in 1984 established that this area is at high risk for MS. We updated the frequency estimates of the disease by adopting a complete enumeration approach. On 31 December 2005, 50 MS patients (36 women and 14 men) yielded a crude prevalence rate of 166.7 per 100, 000 (95% CI 123.7-220), 235.3 (95% CI 165-327.4) for women and 95.2 (95% CI 52-160) for men. The average incidence from 1990 to 2005 was 7.9 (95% CI 5.3-11.1) per 100,000, 11.7 (95% CI 7.6-17.3) for women and 3.9 (95% CI 1.7-7.7) for men. We did not detect any significant temporal trend over the study period. These results confirm that in San Marino the disease occurs more frequently than that suggested in the past and support the data on MS frequency in continental Italy. The marked increase in MS prevalence ratio is partly due to the increasing survival of patients and the accumulation of new incidence cases owing to the reduction in diagnostic latency for better quality of neurological diagnostic procedures. However, an increased incidence of the disease could be considered.

Prevalence and incidence of multiple sclerosis in Salerno (southern Italy) and its province

Many multiple sclerosis (MS) prevalence studies in Italian northern and central areas, since 1980, have put Italy in a high risk zone; none concerns southern Italy. The MS registry of Salerno Center was reviewed, including the city and 16 towns at different distances (9-149 km) better connected to our Center. Population screened: 259 681 persons (Salerno = 136 678; province = 123 003). Prevalence day was December 31, 2005. Data on 186 patients were collected of which 55 were males, 131 females; crude total prevalence = 71.6263 (62.03-82.303, ranging from 50.1128 (Oliveto Citra) to 431.499 (Controne). Salerno prevalence rate is 70.9697 (57.41-86.583); standardized = 72.02. Incidence rate ranges from 2.38585 (1.6-3.39) (1991-95) to 4.31997 (3.24-5.6) (2001-05). Our data can be underestimated because some patients could have skipped the local center. This emphasizes that the results, except for Sardinia, are comparable to Italian literature data. They confirm that this territory is a high risk area for MS. There is also an indirect indication against a latitude gradient for MS.

Multiple sclerosis in the province of Ferrara : evidence for an increasing trend

BACKGROUND

Epidemiological studies on the distribution of multiple sclerosis (MS) conducted in the Mediterranean area in the last two decades have disclosed a significant increase in frequency of the disease, indicating caution when a latitude-related model of MS is accepted. Previous descriptive surveys in the province of Ferrara, northern Italy, carried out by our own epidemiological research group, have established that this area is at high risk for MS.

OBJECTIVE

To confirm the above assumption and to update MS frequency estimates in this area.

DESIGN AND SETTING

We conducted a community-based intensive prevalence and incidence study, by adopting a complete enumeration approach.

RESULTS

On December 31, 2004, 423 patients (300 women and 123 men) suffering from definite or probable MS (Poser's criteria) living in the province of Ferrara, yielded a crude prevalence rate of 120.93 (95 % CI, 110.05-134.23) per 100,000, 164.26 for women and 73.59 for men. The average incidence from 1990 to 2003 was 4.35 per 100,000 (95 % CI, 3.77-4.99), 5.91 for women and 2.63 for men. The incidence rate,which was relatively stable during the previous 25 years (1965-1989) with a mean rate of 2.3 per 100,000, increased to a value of 3.39 per 100,000 in the period 1990-1994, 4.09 per 100,000 in the period 1995-1999 and 3.84 per 100,000 in the period 2000-2003.

CONCLUSIONS

These results confirm that in Ferrara MS occurs more frequently than suggested by the geographic- related distribution model and, based on other recent national surveys, support the view that northern Italy is a high-risk area for the disease. The marked increase in MS prevalence rate, in comparison with previous investigations, is in part due to the increasing survival of patients as a result of improved supportive care and the accumulation of new incidence cases owing to the reduction in diagnostic latency for better quality of neurological diagnostic procedures. The incidence in the province of Ferrara was found to slowly change with an incremental trend,which cannot only be attributed to improvements in diagnostic ability. Environmental risk factors in genetically predisposed people over time could be considered.

The epidemiology of multiple sclerosis in Europe

Multiple sclerosis (MS) is a chronic and potentially highly disabling disorder with considerable social impact and economic consequences. It is the major cause of non-traumatic disability in young adults. The social costs associated with MS are high because of its long duration, the early loss of productivity, the need for assistance in activities of daily living and the use of immunomodulatory treatments and multidisciplinary health care. Available MS epidemiological estimates are aimed at providing a measure of the disease burden in Europe. The total estimated prevalence rate of MS for the past three decades is 83 per 100,000 with higher rates in northern countries and a female:male ratio around 2.0. Prevalence rates are higher for women for all countries considered. The highest prevalence rates have been estimated for the age group 35-64 years for both sexes and for all countries. The estimated European mean annual MS incidence rate is 4.3 cases per 100,000. The mean distribution by disease course and by disability is also reported. Despite the wealth of epidemiological data on MS, comparing epidemiological indices among European countries is a hard task and often leads only to approximate estimates. This represents a major methodological concern when evaluating the MS burden in Europe and when implementing specific cost-of-illness studies.

Bayesian mapping of multiple sclerosis prevalence in the province of Pavia, northern Italy

The geographical analysis of a disease risk is particularly difficult when the disease is non-frequent and the area units are small. The practical use of the Bayesian modelling, instead of the classical frequentist one, is applied to study the geographical variation of multiple sclerosis (MS) across the province of Pavia, Northern Italy. 464 MS-affected individuals resident in the province of Pavia were identified on December 31st 2000. The overall prevalence was 94 per 100,000 inhabitants. This estimate indicates an increasing MS prevalence in the province, in accordance with the vast majority of the Italian areas where prevalence studies have been repeated. We mapped the geographical variation of MS prevalence across the 190 communes of the province both with a classical approach and a Bayesian approach. The frequentist approach produced an extremely dishomogeneous map, while the Bayesian map was much smoother and more interpretable. Our study underlines the usefulness of Bayesian methods to obtain reliable maps of disease prevalence and to identify possible clusters of disease where to carry out further epidemiological investigations.

Multiple sclerosis and autoimmune diseases

An autoimmune background is thought to characterize the families of multiple sclerosis (MS) patients, but disease patterns and HLA-DR association seem to vary considerably among different ethnic groups. We investigated the prevalence of autoimmune diseases in 245 MS patients and 245 age- and sex-matched normal controls (NC), originating from and living in North-east Italy, and their first degree relatives, using a case-control method. Further, HLA-DRB1 expression was analysed in MS and NC. The following significant findings were observed: 1) a significant excess of autoimmunity in first-degree relatives of MS patients (p = 0.000), 2) an association of MS with Type 1 diabetes mellitus (T1DM) (p = 0.02), 3) an increase in DR4 expression (namely DRB1*0401) in MS patients from families with multiple autoimmune pathology compared with reference MS patients (p=0.02) and NC (p=0.01). We conclude that the risk of autoimmune disease is higher in first-degree relatives of MS patients and that disease association and HLA-DR expression in North-east Italy differs from other geographic regions of Europe.

The prevalence of multiple sclerosis in the north?west Italian province of Genoa

The objective of this study was to assess the prevalence of multiple sclerosis (MS), calculated as point prevalence on 31 December 1997, in the province of Genoa, North-western Italy.

METHODS

The province of Genoa is located in North-western Italy, an area of 1,835 km(2). On the point prevalence day the population consisted of 913,218 inhabitants. MS cases were identified by analysing archives of the hospitals with neurological or rehabilitation wards, neurologists serving the community, files of local chapters of the Italian MS society, all requests for oligoclonal bands analysis on CSF in the studied area. Patients included in the study were MS cases diagnosed before 31 December 1997 according to the Poser criteria resident in the province under study.

RESULTS

A total of 857 subjects were alive and residing in the province of Genoa on the prevalence day. The overall crude prevalence rate was 94 per 100,000 (95% CI 88-100); 291 were males (34%) with a crude prevalence of 67 per 100,000 (95 % CI 60-76) and 566 were females (66%) with a prevalence of 118 per 100,000 (95% CI 108-128). The female/male ratio was 1.9. When age and sex were adjusted to the Italian standard population of 1991 prevalence was 85 per 100,000. Five hundred and thirty two out of the 857 patients agreed to be interviewed. The interviewed sample was representative of the prevalence sample: sex and gender distributions were identical in the two samples. The overall mean age was 48 (+/-13) years (48 +/-12 years in males; 48+/-14 years in females). Mean disease duration was 15 (+/-10) years for males and 16 (+/-11) years for females. Two hundred and ninety one (55 %) subjects had a relapsing remitting (RR) clinical course, 150 (28%) were secondary progressive (SP) and 91 (17%) were primary progressive (PP). Mean EDSS score was 5 (+/- 2; median 5). The mean age at time of onset was 33 (+/-10) years for males and 32 (+/- 11) years for females. The disease onset was monosymptomatic in 76% (n=407) patients and polysymptomatic in 24% (n=125). The mean length of time between clinical onset and diagnosis was 5 (+/- 6) years.

CONCLUSION

We confirmed that the province of Genoa is a very high risk area for MS. We found a high rate of patients with a PP course; also the proportion of patients with high disability scores is greater compared to previous studies.

Multiple sclerosis in Nord-Trøndelag County, Norway: a prevalence and incidence study

OBJECTIVE

To calculate the prevalence and incidence of multiple sclerosis (MS) in Nord-Trøndelag County, Norway.

MATERIAL AND METHODS

The study comprised everyone diagnosed with MS according to the Poser criteria. On 1 January 2000 a total of 208 were identified: 130 women (62.5%) and 78 men (37.5%). We calculated the crude and age-adjusted annual incidence rates from 1974 to 1999.

RESULTS

The prevalence on 1 January 2000 was 163.6 of 100,000, 204.8 of 100,000 for women and 122.6 of 100,000 for men. The age-adjusted annual incidence increased from 3.9 to 5.6 per 100,000 from 1974 to 1999; women from 4.6 to 6.3 and men from 2.2 to 4.4. After 1984, the incidence among women increased most, peaking at 10.2 per 100,000 in 1984-88.

CONCLUSIONS

MS incidence is increasing in Nord-Trøndelag County. The prevalence is among the highest ever in Norway.