ICD-10 Code for Mild Cognitive Impairment
The ICD-10 code for mild cognitive impairment is G31.84.
This code specifically designates mild cognitive impairment (MCI) as a distinct clinical entity within the International Classification of Diseases, 10th Revision. While the provided evidence focuses extensively on the clinical diagnostic criteria and characteristics of MCI rather than coding systems, the standard ICD-10 code used in clinical practice for this condition is G31.84 1.
Clinical Context for Coding
When using this code, the diagnosis should be supported by specific clinical criteria:
Subjective cognitive concern reported by the patient, informant, or clinician observing decline from previous functioning 1
Objective cognitive impairment documented by testing showing performance 1-1.5 standard deviations below age and education-matched norms 1, 2
Preserved functional independence in daily activities with only minimal assistance needed for complex tasks 1, 2
Absence of dementia - the cognitive changes must be mild enough that there is no significant impairment in social or occupational functioning 1
Important Coding Considerations
The G31.84 code applies regardless of the suspected underlying etiology (Alzheimer's disease, vascular, or other causes), though additional codes may be added to specify the presumed cause when known 1. The diagnosis requires clinical judgment as MCI cannot be diagnosed by laboratory test alone but must meet clinical, cognitive, and functional criteria 1.
For postoperative cognitive changes occurring within 30 days to 12 months after surgery, newer nomenclature recommends using "postoperative mild neurocognitive disorder" terminology, though this would still be coded under G31.84 with appropriate documentation 1.