Is frontotemporal lobar degeneration a rare disorder? Evidence from a preliminary study in Brescia county, Italy.

Frontotemporal Lobar Degeneration (FTLD) has always been considered a rare disorder, but only a few epidemiologic studies are available. The aim of the present work was to ascertain all FTLD patients in a Northern Italy area from January 2001 to December 2008, and to estimate the disease prevalence. On the census day, 213 FTD patients were still alive, resulting in an overall prevalence of 17.6 per 100,000 inhabitants. The prevalence of FTLD in patients aged 45-65 years was 22 per 100,000 inhabitants (95% CI=17-27). The prevalence of FTLD was the highest in patients aged 66-75 (78 per 100,000 inhabitants, 95% CI=56-100), and it was still high over 75 years (54 per 100,000 inhabitants, 95% CI=36-69). FTLD is a more common form of dementia than previously recognized. Our results claimed that FTLD is not only an early-onset disorder, but it is frequent in advanced age as well.