White blood cells and cortisol after sleep deprivation and recovery sleep in humans

Sleep deprivation (SD) has enriched our treatment programme for major depre ssion. SD has been demonstrated to modify different host defence activities . There is some evidence that there are reciprocal relationships between im mune function and increased hypothalamic-pituitary-adrenocortical (HPA) axi s activity in depression. We therefore investigated the number of leukocyte s, granulocytes, monocytes, lymphocytes, B cells, T cells. helper T cells, cytotoxic T cells, NK cells and salivary cortisol in 10 healthy men before and after total SD (TSD) as well as after recovery sleep. Blood samples wer e drawn on 3 consecutive days at 7 am, 1 pm and 7 pm, respectively. Compari son of the 7 am values by contrast analysis yielded significant differences for granulocytes (p = 0.044) and NK cells (p = 0.001) after SD and recover y sleep. NX cells decreased and granulocytes increased after SD and after r ecovery sleep. Significant differences between single points in time across the day were found for granulocytes (p = 0.022), monocytes (p = 0.031). T cells (p = 0.005), helper T cells (p = 0.001), cytotoxic T cells (p = 0.005 ) and NK cells (p = 0.017). No significant difference could be detected for leukocytes, Ivmphocytes and B cells counts. These results favour the thesi s that SD and recovery sleep lead to changes in the distribution of periphe ral leukocytes, especially in a reduction of NK cells after SD and recovery sleep. The cortisol rhythm was affected neither by SD nor recovery sleep.