I have had PTSD and non allergic asthma for 42-years after a chemical explosion in vietnam. I do not think of the injury or have nightmares odd smells initiate asthma attacks from explosion.The smooth muscles in my airways and stomach swell from the overproduction of histamines(PTSD). I can assure you that mental disease has nothing whatsoever to do with PTSD it is intrinsic reversible and curable with pulmonary function and histamine challenge testa along with complete physical. A doctor told me that a psychologist knows as much about PTSD as a used car saleman. I totally agree. Asthma is from allergies and not linked to military service non allergic asthma is from the sights sounds smells and injuries of war is intrinsic and curable with medication and understanding.  Fred Rowles