Increasing Incidence of Multiple Sclerosis in the Province of Sassari, Northern Sardinia

Sardinia is a high-risk area for multiple sclerosis (MS), with prevalence rates of 150 per 100,000 population. The study included 689 MS patients (female-male ratio 2.6) with disease onset between 1965 and 1999 in the province of Sassari. The mean annual incidence rate increased significantly from 1.1 per 100,000 population in 1965–1969 to 5.8 in 1995–1999, with no significant difference for gender and province sub-areas. The mean age at onset increased significantly during the same period from 25.7 to 30.6 years, while the proportion of patients with progressive initial course declined over time. The marked increase of MS incidence and the change of MS clinical phenotype over time cannot be explained by ascertainment bias only, thus pointing to a corresponding change in the distribution of exogenous risk factors in this highly genetically stable population

Sardinia, a high-risk area for multiple sclerosis: a prevalence and incidence study in the district of Alghero

Findings from small descriptive studies carried out in the last few years in Sardinia suggest that this region is now of high rather than medium risk for multiple sclerosis. It is uncertain whether this high prevalence reflects a different approach in case finding over time or a true change in disease occurrence. We report the results of a prevalence and incidence survey conducted in the district of Alghero, a community of 78,000 people in northwest Sardinia. Based on data from 31 patients, the average annual incidence for the period 1971 through 1980 was 4.1 per 100,000. On December 31, 1980, the prevalence rate was 59 per 100,000. The results support the view that Sardinia is now a high-risk area for multiple sclerosis, and further suggest a rise in the occurrence of the disease in recent years

Multiple sclerosis epidemiology in Sardinia: evidence for a true increasing risk

Objectives To update prevalence and incidence rates of MS among Sardinians. Materials and methods The present work is a "spider" kind of population based survey, conducted over the interval 1968-97, on patients with MS (Poser criteria) living in the province of Sassari, Northern Sardinia (454,904 population). Results A crude total prevalence rate of 144.4 per 100,000, an onset-adjusted prevalence rate of 149.7 per 100,000 and an average annual incidence rate of 8.2 for the period 1993-7 were found. Conclusion Repeated epidemiological assessments of MS in Sardinia over decades have shown that the island is at high risk for MS. The present work highlights that MS incidence in Sardinia has been increasing over time. Although a substantial and widely spread improvement in MS case ascertainment can be postulated as the reason for such observations, a comparison between our data and those recently reported from a more industrialized province in Northern Italy seems to prove an at least partially real increase in MS risk among Sardinians and favours the hypothesis of a MS "Sardinian focus" as related to its latitude