Sleep disturbances and @entity73 are common non-motor manifestations of @entity191 ( @entity191 ). Recent studies suggest that sleep spindles and slow waves play a role in brain plasticity mechanisms and are associated with cognitive performance. However, it remains unknown whether these sleep parameters could serve as markers of @entity73 in @entity191 . Therefore, we examined whether alterations in sleep spindles and slow waves at baseline visit were associated with increased likelihood of developing @entity303 at follow-up in @entity191 . Sixty-eight nondemented @entity191 @entity1 (64.9    8.8  years old; 46 @entity1 ) participated in the study, along with 47 healthy individuals (65.0    10.6  years old; 30 @entity1 ). All @entity1 underwent baseline polysomnographic recording and a comprehensive neuropsychological assessment. Sleep spindles (12-15  Hz) and slow waves (>75   V and <4  Hz) were automatically detected on all-night non-rapid eye movement sleep electroencephalography. At follow-up (mean: 4.5  years later), 18 @entity191 @entity1 developed @entity303 (70.2    7.6  years old; 13 @entity1 ) and 50 remained @entity303 -free (63.0    8.5  years old; 33 @entity1 ). Sleep spindle density and amplitude were lower in @entity191 @entity1 who converted to @entity303 compared with both @entity1 who remained @entity303 -free and controls, mostly in posterior cortical regions (p < 0.05). @entity303 -free @entity191 @entity1 were intermediate between @entity303 @entity1 and controls, with lower baseline sleep spindle density in all cortical areas compared with controls (p < 0.01). In @entity191 @entity1 , lower sleep spindle amplitude in parietal and occipital areas was associated with poorer visuospatial abilities. Although slow wave amplitude was lower in @entity191 @entity1 compared with controls (p < 0.0001), no difference was observed between those who developed or did not develop @entity303 . Results demonstrate non-rapid eye movement sleep electroencephalographic abnormalities in @entity191 @entity1 . Sleep spindle activity was particularly impaired in @entity191 @entity1 who developed @entity303 , with a more posterior topographic pattern. Sleep spindle alterations are associated with later development of @entity303 in @entity191 , and thus may serve as an additional marker of @entity73 in these @entity1 .

Sleep spindles in @entity191 may predict the development of XXXX .

@entity303 :: ('MESH:D003704', 'Disease') :: ['Dementia', 'dementia'] @entity73 :: ('MESH:D003072', 'Disease') :: ['cognitive impairment', 'cognitive decline'] @entity1 :: ('9606', 'Species') :: ['participants', 'patients', 'men'] @entity191 :: ('MESH:D010300', 'Disease') :: ["Parkinson's disease", 'demented PD', 'PD']
@entity303 :: (MESH:D003704,Disease) :: ['dementia']
