Clinical incidence of dementia with Lewy bodies

Dementia with Lewy bodies (DLB) has only relatively recently been acknowledged as an independent neurodegenerative entity. Until now few epidemiological prevalence studies have been carried out that include DLB and there are no studies about its incidence. The aim of this study is to determine the annual clinical incidence of DLB. We performed an observational retrospective study of the diagnosis of all the individuals who were attended at the UVAMID (Memory and Dementia Assessment Unit) between 1999 and 2001. The clinical assessment was performed in a standardised manner following the UVAMID protocol, which includes the medical history, obtained by interviewing the patient and a reliable informant, a general medical and neurological check up, neuropsychological exploration and a set of complementary tests. The incidence of DLB in clinical practice was found to be 26/100,000 cases per year. By age groups, a progressive increase in incidence was seen until the 80 84 year old bracket and 63% of the cases of DLB were males. The results of this study show that cases of DLB made up 2% of the total number of new annual cases. The main limitation of this study lies in the fact that, because patients were referred to clinic from primary health care centres, they do not constitute a representative sample that is clinically unbiased, and this imposes restraints on the extrapolation of results.