take) MIBG myocardial scintigraphy suggest ing sympathetic denervation; and prominent
slow-wave activity on the electroencephalo gram with temporal lobe transient waves.
Functional Consequences of Major or Mild 
Neurocognitive Disord er With Lewy Bodies
Individuals with NCDLB are more  functionally impaired than would be expected for their
cognitive deficits when contrasted to individuals with other neurodegenerative diseases,
such as Alzheimer’s disease. This is largely a result of motor and autonomic impairments,
which cause problems with toileting, transfer ring, and eating. Sleep disorders and prom-
inent psychiatric symptoms may also add to functional di fficulties. Consequently, the qual-
ity of life of individuals with NCDLB is often significantly worse than that of individuals
with Alzheimer’s disease.
Differential Diagnosis 
Major or mild neurocognitive diso rder due to Parkinson’s disease. A key differenti-
ating feature in clinical diagnosis is the tempor al sequence in which the parkinsonism and
the NCD appear. For NCD due to Parkinson’s disease, the individual must develop cog-
nitive decline in the context of established Parkinson’s disease; by convention, the decline
should not reach the stage of major NCD until at least 1 year after Parkinson’s is diagnosed.
If less than a year has passed since the onset of motor symptoms, the diagnosis is NCDLB.
This distinction is clearer at the major NCD level than at the mild NCD level. 
The timing and sequence of parkinsonism an d mild NCD may be more difficult to de-
termine because the onset and clinical presentation can be ambiguous, and unspecified
mild NCD should be diagnosed if the othe r core and suggestive features are absent.