Estimated prevalence of multiple sclerosis in Italy in 2015

Abstract

Italy is a high risk area for multiple sclerosis (MS) as confirmed by the numerous prevalence and incidence studies conducted in several regions/districts of the country. Nevertheless, there are no recent published epidemiological data, nor studies about the total prevalence of MS in Italy. Our aim was to update as of 2015 the prevalence rates of MS in different geographical areas using already published epidemiological studies, and to estimate the overall prevalence of the disease in Italy. We made a search in MEDLINE database of all published studies on epidemiology of MS in Italy. Then, we applied, to the already published prevalence data, the last published incidence and mortality rates to recalculate, as of 2015, the prevalence of MS. So, we calculated the mean prevalence rate from our extrapolations, and we applied it to the population in 2015 to estimate the number of MS patients in Italy. Our prevalence extrapolations ranged from 122 to 232 cases/100,000 in the mainland and Sicily, with an average of 176/100,000, and from 280 to 317 cases/100,000 in Sardinia with an average of 299/100,000. Applying these media to the Italian population in 2015, we obtained an estimate of more than 109,000 MS patients in Italy. Our estimates were higher than the latest published rates but consistent with the annual increase of prevalence due to incidence that exceeds mortality, with the increase of survival and, maybe, with the probable increase of incidence.

The Prevalence of Multiple Sclerosis in the Metropolitan Area of Rome: A Capture-Recapture Analysis

“…A recent study [3] noted how, as of 2015, Italy is a high-risk area for MS (average prevalence 110 per 100,000) with no north-south gradient, showing a trend toward an increased prevalence, in line with similar appraisals of nationwide prevalence in other European countries and in North America. Nonetheless, most of the epidemiological data on which these conclusions have been extrapolated have been collected from the islands and in the Northern part of the country.…”

“…While there are currently no whole European-level estimates, it shall be reported that prevalence estimates in other regions of Europe are generally lower, with the notable exceptions of Southern Italy and Sardinia, Scotia, Northern Ireland, and specific regions of Scandinavia [12]. The Italian prevalence rate reported in [3] is 176 per 100,000 (when excluding Sardinia), which shall be compared with our 147.5 per 100,000 after standardization.…”

“…Several studies have been conducted to address the incidence and prevalence of MS in different cities and provinces of Italy. Differing prevalence rates have been estimated among the largest cities of the mainland, where larger prevalence rates have been identified in the northern part of the country [3-6]. It has been speculated though that the variability of prevalence is in part simply due to the limited epidemiological data available from the central-southern regions [7-10].…”

“…This leads to biased estimates even after aggregation at larger area levels (e.g., regional, national or even European). Some authors indeed clearly point out the risk of underestimation of the true prevalence rates [3, 12]. An additional widespread problem limiting the possibilities for epidemiological comparisons over time and space is that methods of data collection and analysis are often non-standardized.…”

“…Sardinia and Sicily (the largest islands of the country) are high-risk areas, with an average prevalence of 299 and 176 per 100,000 population respectively; meanwhile, the rest of the country has a prevalence of approximately 110/100,000 [3]. Several studies have been conducted to address the incidence and prevalence of MS in different cities and provinces of Italy.…”