RT Journal Article
SR Electronic
T1 Poor attentional function predicts cognitive decline in patients with non-demented Parkinson’s disease independent of motor phenotype
JF Journal of Neurology, Neurosurgery & Psychiatry
JO J Neurol Neurosurg Psychiatry
FD BMJ Publishing Group Ltd
SP 1318
OP 1323
DO 10.1136/jnnp.2008.147629
VO 79
IS 12
A1 J-P Taylor
A1 E N Rowan
A1 D Lett
A1 J T O’Brien
A1 I G McKeith
A1 D J Burn
YR 2008
UL http://jnnp.bmj.com/content/79/12/1318.abstract
AB Background: Postural instability gait difficulty (PIGD) motor phenotype in Parkinson’s disease (PD) is associated with a faster rate of cognitive decline than in tremor dominant cases and may be a risk factor for incident dementia. People with PD display attentional deficits; however, it is not clear whether attentional deficits in patients with non-demented PD are associated with (i) PIGD phenotype and/or (ii) subsequent cognitive decline. Aims: (i) To examine rates of cognitive decline (Mini-Mental State Examination (MMSE) and Cambridge Cognitive Examination (CAMCOG)) over 3 years in subjects with non-demented PD aged over 65 years, (ii) using Cognitive Drug Research computerised assessment test battery, determine the rate of change in power of attention (PoA) scores over time (sum of mean choice reaction time, simple reaction time and digit vigilance reaction time scores), (iii) determine whether the PIGD phenotype is associated with changes in PoA and (iv) establish whether baseline PoA is associated with subsequent cognitive decline. Results: 14 subjects (38%) were classified as PIGD motor phenotype at baseline. Cognitive decline was greater in PIGD compared with non-PIGD subjects (p⩽0.02). PIGD phenotype was not associated with baseline PoA score although it was associated with subsequent worsening in PoA (mean PoA increase/year: non-PIGD subjects 11.4 ms; PIGD subjects 244.0 ms; p = 0.01). Higher baseline PoA scores were associated with greater cognitive decline (MMSE, p = 0.03; CAMCOG, p = 0.05) independent of PIGD status. Conclusion: PIGD phenotype and attention deficits are independently associated with a greater rate of cognitive decline in patients with non-demented PD. We propose that subtle attentional deficits in patients with non-demented PD predict subsequent cognitive impairment.