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 and 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 other core and suggestive features are absent.
Lewy body pathology frequently coexists with Alzheimer’s disease and cerebrovascular disease pathology, particularly among the oldest age groups. In Alzheimer’s disease, there is concomitant synuclein pathology in 60% of cases (if amygdala-restricted cases are in- cluded). In general, there is a higher rate of Lewy body pathology in individuals with de- mentia than in older individuals without dementia.
A. The criteria are met for major or mild neurocognitive disorder.
B. The clinical features are consistent with a vascular etiology, as suggested by either of the following: 1. Onset of the cognitive deficits is temporally related to one or more cerebrovascular events.
2. Evidence for decline is prominent in complex attention (including processing speed) and frontal-executive function.
C. There is evidence of the presence of cerebrovascular disease from history, physical examination, andlor neuroimaging considered sufficient to account for the neurocog- nitive deficits.
D. The symptoms are not better explained by another brain disease or systemic disorder.
Probable vascular neurocognitive disorder is diagnosed if one of the following is pres- ent; otherwise possible vascular neurocognitive disorder should be diagnosed: 1. Clinical criteria are supported by neuroimaging evidence of significant parenchymal in- jury attributed to cerebrovascular disease (neuroimaging-supported).
2. The neurocognitive syndrome is temporally related to one or more documented cere- brovascular events.
3. Both clinical and genetic (e.g., cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) evidence of cerebrovascular disease is present.
Possible vascular neurocognitive disorder is diagnosed if the clinical criteria are met but neuroimaging is not available and the temporal relationship of the neurocognitive syn- drome with one or more cerebrovascular events is not established.
Coding note: For probable major vascular neurocognitive disorder, with behavioral dis— turbance, code 290.40 (F01.51). For probable major vascular neurocognitive disorder, without behavioral disturbance, code 290.40 (F01.50). For possible major vascular neuro- cognitive disorder, with or without behavioral disturbance, code 331.9 (631.9). An addi- tional medical code for the cerebrovascular disease is not needed.
For mild vascular neurocognitive disorder, code 331.83 (631.84). (Note: Do not use an additional code for the vascular disease. Behavioral disturbance cannot be coded but should still be indicated in writing.)
The diagnosis of major or mild vascular neurocognitive disorder (NCD) requires the es- tablishment of an NCD (Criterion A) and the determination that cerebrovascular disease is the dominant if not exclusive pathology that accounts for the cognitive deficits (Criteria B and C). Vascular etiology may range from large vessel stroke to microvascular disease; the presentation is therefore very heterogeneous, stemming from the types of vascular lesions and their extent and location. The lesions may be focal, multifocal, or diffuse and occur in various combinations.