The potential role of hypocortisolism in the pathophysiology of PTSD and psoriasis

Different physical, chemical and psychological stressors can. provoke a uni que but different endocrine response involving activation of the hypothalam o-pituitary-adrenal (HPA) axis. Inability of adequate compensatory reaction can lead to many disorders. The aim of our study was comparison of cortiso l values in diseases provoked by various stressors. Our investigation inclu ded 34 posttraumatic stress disorder (PTSD) patients, as an example of diso rder caused by extremely strong, acute stressful stimulus, 19 psoriatic pat ients, as art example of chronic stress stimulus and 17 healthy volunteers. In each patient we determined 24-hour urinary cortisol, serum cortisol at 8 a.m. and 5 p.m., and cortisol in dexamethasone suppression, test by the s tandard radioimmunoassay (RIA) method. PTSD patients showed lower urinary 2 4-hour cortisol values, (361 +/-28 nmol/24(h)), "stronger" circadian. rhyth m of serum cortisol (595+/-57 nmol / l at 8 a.m. and 242+/-23 nmol / l at 5 p.m.) and attenuated suppression of cortisol in dexamethasone suppression, test (197+/-45 nmol/l) in. comparison to healthy volunteers (590+/-87 nmol / 24h urine, 590+/-32 nmol/l at 8 a.m., 402+/-31 nmol / l, and < 86 nmol / l in dexa test). Psoriatic patients showed markedly lower 24-hour cortisol values (150+/-98 nmol/24h), even in comparison, to PTSD patients, then seru m cortisol values (404+/-138 nmol / l at 8 a.m., 187+80 nmol / l at 5 p. m. ) and enhanced suppression of cortisol (23+/-5 nmol / I). The model of atte nuated feedback inhibition in PTSD patients shows that they are unusually r eactive to stress and represents an alternative model of acute stress react ion to extremely strong stressful stimulus. Unusually Low cortisol values i n psoriatic patients correlate to our hypothesis that in chronic stress-rel ated disease, as psoriasis is, exists, by still undefined mechanism, altere d HPA axis function which is obviously incompetent to realise its immunoreg ulatory function, so consequentially, clinical signs of psoriasis persist.