Subtypes of Dementia with Lewy Bodies: Clinical Features, Survival, and Apolipoprotein E Effect.

Abstract

Dementia with Lewy bodies (DLB) is a progressive neurodegenerative disease with various clinical symptoms. Limited data have described the clinical subtypes of DLB. We aimed to compare clinical subtypes of DLB according to initial symptoms and to study the effect of Apolipoprotein E (APOE) gene in DLB. We included DLB patients classified into three groups based on initial symptoms: non-motor onset (cognitive and/or psychiatric) (NMO-DLB), motor onset (parkinsonism and/or gait disorders) (MO-DLB), and mixed onset (non-motor and motor symptoms) (MXO-DLB). Clinical and APOE genotype associations and survival were analyzed. A total of 268 patients were included (NMO-DLB = 75%, MXO-DLB = 15.3%, MO-DLB = 9.7%). Visual hallucinations were more frequent (p = 0.025), and attention was less commonly impaired in MXO-DLB (p = 0.047). When adjusting with APOE ɛ4 status (APOE genotype performed in 155 patients), earlier falls and frontal lobe syndrome were more common in MXO-DLB (p = 0.044 and p = 0.023, respectively). The median MMSE decline was 2.1 points/year and the median FAB decline was 1.9 points/year, with no effect of clinical subtypes. Median survival was 6 years. It was similar in DLB subtypes (p = 0.62), but shorter for patients with memory symptoms at onset (p = 0.04) and for males (p = 0.0058). Our study revealed a few differences between DLB clinical subtypes. APOE ɛ4 appears to be associated with earlier falls and a higher prevalence of frontal syndrome in MXO-DLB. However, DLB clinical subtypes did not impact on survival. Nevertheless, survival analysis identified other poor prognosis factors, notably inaugural memory impairment and male gender.