Disturbed function of the growth hormone axis and the HPA axis in obsessive compulsive disorder

Information on the function of the growth hormone axis and the HPA axis in obsessive compulsive disorder is scarce. In this study, 9 inpatients with a DSM-IV diagnosis of OCD without comorbid major depression (Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score >15; HAMD-21 total score <17) and 9 healthy matched controls were included. Blood of patients (7 males) 31.8±9.3 years, Y-BOCS: 27.3±4.3, HAMD-21: 13.3±1.9) and controls (7 males, 31.6±9.1 years) was drawn every 20min between 2300h and 0700h. Mean plasma GH levels peaked at 0040h, however this peak was significantly blunted in patients (maximum 4.3±1.5ng/ml) compared to controls (maximum 12.3±4.0ng/ml; p<0.05). In patients but not controls two other, smaller peaks were observed (0220h and 0620h). Secretion patterns of cortisol and ACTH were similar in both groups, in OCD, however, at a higher level. Area under the curve plasma concentrations of both ACTH (p<0.05) and cortisol (p<0.005) were significantly greater in patients with OCD (ACTH: 674.3±57.4; cortisol: 2148.4±271.7) than in controls (ACTH: 460.2±61.0; cortisol: 1191.2±124.1). In conclusion, our findings suggest that the activity of the growth hormone axis in patients with OCD is suppressed and the activity of the HPA axis is increased.