Post-traumatic dysphoria was a psychological condition.
Six months after the incident aboard the USS Ibn Majid, Commander Cristóbal Rios was discharged from Starfleet. The reason cited for the discharge was post-traumatic dysphoria. (PIC: "Broken Pieces")
Dysphoria is defined as "a state of unease or generalized dissatisfaction with life", so post-traumatic dysphoria can be determined to mean "a state of unease or generalized dissatisfaction with life following trauma"