Prevalence of multiple sclerosis in Health District III, Murcia, Spain.

BACKGROUND: The prevalence of multiple sclerosis (MS) varies throughout the world, and available epidemiological data suggest a progressively increasing prevalence of MS in Spain. The objective of this study was to calculate MS prevalence in Health District III of the autonomous community of Murcia in Spain. METHODS: This is an observational, cross-sectional, descriptive study. The prevalence of MS in Health District III in the Region of Murcia, which includes the municipalities of Lorca, Totana, Águilas, Puerto Lumbreras and Aledo, was calculated from the total population (171,040 inhabitants), and among native Spanish citizens only (137,659 persons). Healthcare and demographic data were obtained from three sources: 1) OMI-AP: the local primary care computer system containing the medical records of all subscribers; 2) the medical record database of the Hospital Rafael Mendez (the single hospital in the district); and 3) the records of the AEMA III Multiple Sclerosis Association to which patients from this healthcare district belong. Data from these three sources were combined to check the accuracy and completeness of the patient records. RESULTS: The prevalence of MS among the general population of this district, including non-Spanish individuals, was 71.9 per 100,000 inhabitants (95% CI=60-85). Prevalence among the native Spanish population was 82.0 per 100,000 (95% CI=68-98). Considering prevalence by sex, it was 118.1 per 100,000 (95% CI: 95-146) in the female native Spanish population, and 45.4 per 100,000 (95% CI: 31-64) in the male native Spanish population. The prevalence in the native Spanish population in this district was calculated by sex and age (grouped by decades). A peak was observed among women aged between 20 and 29 years: 234.2 per 100,000 inhabitants (95% CI: 151-361). CONCLUSION: Our results suggest that the population in this healthcare district presents a risk of MS similar to that recently reported in other regions of Spain, which is higher than in previous decades.

Association study and meta-analysis of Alzheimer's disease risk and presenilin-1 intronic polymorphism.

Numerous studies have tested for associations between an intronic polymorphism (rs165932) of presenilin-1 (PS-1) gene and the risk of Alzheimer's disease (AD), but results have been conflicting. To throw light on this issue, we investigate the possible involvement of PS-1 genotype in a case-control study based on a relatively stable population in Spain and a meta-analysis of published studies. An examination was conducted of 85 patients with probable or possible AD, along with controls from the same community, by using an chi(2) test for homogeneity and a binary logistic regression model. For comparison purposes, a meta-analysis of data from all available published studies was assessed. In our patients, homozygosity of the allele 2 in the PS-1 gene increased for late-onset AD (OR 2.38, 95% CI 1.07-5.29, P<0.05). The presence of at least one allele of apoE was also associated with AD (OR 4.01, 95% CI 1.93-8.34, p<0.05). The regression model showed that, overall, the presence of the apoE epsilon 4 allele and the PS-1 2/2 genotype were independent factors for the development of AD in our sample. In our genotype-based meta-analysis, the PS-1 2/2 genotype was probably related with AD for the European sub-group (fixed effects model, OR 1.19, 95% CI 1.02-1.37, p<0.05), but there are many confusing factors between different studies. Presenilin-1 2/2 genotype is a risk factor for late onset Alzheimer disease in the Spanish population, and probably, for Europeans.