Association of IL-6, hypothalamus-pituitary-adrenal axis function, and depression in patients with cancer.
BACKGROUND
Evidence suggests that cytokines (IL-6) and alteration of the hypothalamic-pituitary-adrenal (HPA) axis play a crucial role in the etiology of depression. Patients with cancer show elevated prevalence rates for depression. The objective of this cross-sectional study was to investigate the associations between these abnormalities and depression.


METHODS
Plasma concentrations of IL-6 and cortisol were measured in cancer patients with (N = 31) and without depression (N = 83). The relative diurnal variation of cortisol (cortisol VAR), expressed in percentage, was calculated.


RESULTS
There was a significant difference in median plasma concentration of IL-6 between the patients with depression and those without (18.7 vs 2.7 pg/mL; P < .001). Relative cortisol VAR was decreased in depressed patients as compared with patients without depression (11.72% vs 60.6%, P = .037). A positive correlation between the depressive symptoms and IL-6 concentration was found (r = 0.469, P < .001). Negative correlations were found between cortisol VAR versus depressive symptoms and cortisol VAR versus IL-6 (r = -0.6, P < .001 and r = -0.52, P < .001, respectively). IL-6 (odds ratio [OR] = 1.1; 95% confidence interval [CI] = 1.0-1.2; P = .006) and cortisol VAR (OR = 1.3; 95%CI = 1.0-1.4; P = .02) are independently associated with depression.


CONCLUSIONS
Depression in cancer is associated with increased plasma IL-6 concentrations and dysfunction of the HPA axis.
Jehn
Christian Friedrich
CF
Department of Oncology and Hematology, University Hospital Charité, Berlin, Germany. christian.jehn@charite.de
Kühnhardt
Dagmar
D
Bartholomae
Andrea
A
Pfeiffer
Sebastian
S
Schmid
Peter
P
Possinger
Kurt
K
Flath
Bernd Christian
BC
Lüftner
Diana
D
D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism; D000368:Aged; D002940:Circadian Rhythm; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood; D003863:Depression / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology*; D003866:Depressive Disorder / Q000503:physiopathology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism / Q000503:physiopathology*; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000503:physiopathology; D009490:Neurosecretory Systems / Q000378:metabolism / Q000503:physiopathology; D010913:Pituitary-Adrenal System / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales
D016207:Cytokines; D015850:Interleukin-6; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone