Veterans with PTSD have 2x More Dementia

The incidence of dementia is increasing even faster than the incidence of cancer!!
This won't help one bit.

Headline:
PTSD Linked to 2-fold Increased Risk for Dementia in Veterans
Caroline Cassels
( from Medscape, on the first study re this question )

Germinal Layers

A human embryo starts out as three layers of tissue known as the ectoderm, mesoderm and endoderm. Most of us know, if we know anything about embryology at all, that the ectoderm becomes the nervous system and skin, the mesoderm becomes the bones and muscle, and the endoderm becomes the gut. But let's get more specific.

What layer originates the parenchyma of the tonsils and thymus?
Ectoderm? Mesoderm? or Endoderm??
( Go ahead, guess. You have a one in three chance. )