That is a very good question. "Major neurocognitive disorder" is, in fact, the new designation used in the international classification as a synonym for "dementia". In Quebec, it is increasingly being used in clinical practice. The committee may need to include these two terms in its documents, since the expression "major neurocognitive disorder" is now used as an equivalent to "dementia" in most fields of practice.
On October 21st, 2022. See this statement in context.