Sibling codes

• G31.80 – Leukodystrophy, unspecified
• G31.81 – Alpers disease
• G31.82 – Leigh's disease
• G31.83 – Neurocognitive disorder with Lewy bodies
• G31.85 – Corticobasal degeneration
• G31.86 – Alexander disease
• G31.87 – Primary progressive apraxia of speech
• G31.89 – Other specified degenerative diseases of nervous system

Excludes1

• age related cognitive decline (R41.81)
• altered mental status (R41.82)
• cerebral degeneration (G31.9)
• cerebrovascular diseases (I60-I69)
• change in mental status (R41.82)
• cognitive deficits following (sequelae of) cerebral hemorrhage or infarction (I69.01-, I69.11-, I69.21-, I69.31-, I69.81-, I69.91-)
• cognitive impairment due to intracranial or head injury (S06.-)
• dementia (F01.-, F02.-, F03.-)
• mild neurocognitive disorder due to a known physiological condition (F06.7-)
• neurologic neglect syndrome (R41.4)
• personality change, nonpsychotic (F68.8)

Inclusion terms

• Mild cognitive disorder NOS
• Mild neurocognitive disorder of uncertain or unknown etiology

Use additional code

• code to identify presence of:
• alcohol abuse and dependence (F10.-)
• exposure to environmental tobacco smoke (Z77.22)
• history of tobacco dependence (Z87.891)
• hypertension (I10-I1A)
• occupational exposure to environmental tobacco smoke (Z57.31)
• tobacco dependence (F17.-)
• tobacco use (Z72.0)

Inherited from G31: Other degenerative diseases of nervous system, not elsewhere classified