In contrast to schizophrenia, delusional disorder is relatively uncommon. Onset is generally involutional, occurring in middle or late adult life. Psychosocial functioning is not as impaired as it is in schizophrenia, and impairments usually arise directly from the delusional belief.

https://www.msdmanuals.com/professio...ional-disorder

the part about relatively uncommon needs to be amended in the case of maga