Altered Hypothalamus-Pituitary-Adrenal Axis Function: A Potential Underlying Biological Pathway for Multiple Concurrent Symptoms in Patients With Advanced Lung Cancer.

OBJECTIVE:Patients with advanced cancer commonly experience multiple symptoms that present as groups or clusters. The present study aimed to examine whether hypothalamus-pituitary-adrenal (HPA) axis dysfunction underlies the concurrent multiple symptoms in patients with advanced cancer. METHODS:Patients' cortisol levels were determined in saliva samples collected after awakening (0, 30, and 60 minutes after awakening) and at nighttime (21:00-22:00 PM) from 46 patients with lung cancer (15.2% women), with a mean (standard deviation) age of 64.3 (9.2) years and 47 healthy participants (53.2% women; age = 62.0 [4.6] years). Cancer-related symptoms were measured using the M.D. Anderson Symptom Inventory (MDASI). RESULTS:Compared with healthy participants, patients showed a significantly reduced cortisol awakening response (F(1,364) = 46.2, p < .001) and had flatter diurnal slope of cortisol (larger β values) (mean [standard error of the mean] = -0.64 [0.06] versus -0.18 [0.05], p < .001). Altered HPA axis function was significantly and adversely associated with performance status and burden of symptoms (all p values < .01). However, each MDASI item varied widely in the degree of association with the HPA axis function. Hierarchical clustering analysis based on Spearman's rank correlation with complete linkage identified that nausea was clustered with vomiting, numbness, and dry mouth, whereas the other nine MDASI core symptoms associated with altered HPA axis function were clustered together. CONCLUSIONS:Altered HPA axis function may be a possible biological pathway that can explain the concurrence of core symptoms in patients with advanced lung cancer.