Major and Mild Neurocognitive Disorders 603
D. The cognitive deficits are not better explai ned by another mental disorder (e.g., major
depressive disorder, schizophrenia).
Specify whether due to:
Alzheimer’s disease  (pp. 611–614)
Frontotemporal lobar degeneration  (pp. 614–618)
Lewy body disease (pp. 618–621)
Vascular disease (pp. 621–624)
Traumatic brain injury  (pp. 624–627)
Substance/medication use  (pp. 627–632)
HIV infection  (pp. 632–634)
Prion disease  (pp. 634–636)
Parkinson’s disease (pp. 636–638)
Huntington’s disease (pp. 638–641)
Another medical condition  (pp. 641–642)
Multiple etiologies (pp. 642–643)
Unspecified  (p. 643)
Coding note: Code based on medical or substance etiology. In some cases, there is need
for an additional code for the etiological medi cal condition, which must immediately pre-
cede the diagnostic code for major neurocognitive disorder, as follows: 
Etiological subtypeAssociated etiological 
medical code for major 
neurocognitive disorderaMajor neurocogni-
tive disorder codebMild neurocogni-
tive disorder codec
Alzheimer’s 
diseaseProbable: 331.0 (G30.9)
Possible: no additional 
medical codeProbable: 294.1x 
(F02.8x)
Possible: 331.9 
(G31.9)c331.83 (G31.84)
(Do not use addi-