Nighttime salivary cortisol as a biomarker of stress and an indicator of worsening quality of life in patients with head and neck cancer: A cross‐sectional study

BACKGROUND: Head and neck cancer (HNC) is a generic term defined on an anatomical–topographic basis to describe malignant tumors located in the oral cavity, pharynx, larynx, and thyroid. A situation commonly presented by individuals with cancer is stress, with evidence indicating a close relationship between stress, behavior, and the immune system with the development and progression of cancer. AIM: To assess the association between stress levels and quality of life among individuals with HNC. METHODS: This was a cross‐sectional study involving 72 HNC patients. The University of Washington Quality of Life Questionnaire was used to assess the quality of life, while the Perceived Stress Scale and salivary cortisol were used to evaluate stress levels. RESULTS: A negative association was found between quality of life and stress levels as indicated by both the PSS and nighttime salivary cortisol. Nighttime salivary cortisol showed the best accuracy estimated by the area under the receiver operating characteristic curve, slightly better than that of PSS. CONCLUSION: Among the time points for saliva sampling, nighttime cortisol was found to have the best accuracy, which was similar to that of the PSS, for the detection of patients with the worst quality of life.