Yes those with an ND disorder will more than likely have comorbid MH disorders. ND is considered a divergence in brain function but that is a theory, and like any disorder and condition like that it has criteria that has changed over years, diagnosis has changed over years.
Schizophrenia has been like that, its an umbrella term really for a number of differering symptoms and types and there continues to be flux in how that is diagnosed and whether that is the correct diagnosis for someone.
To say someone is ND is considering a number of traits and symptoms under an umbrella, it used to be divided into levels of severity, some countries still do this, I suspect it will change back again.