Relationship between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone

BACKGROUND: In university health care settings, students with psychosomatic complaints often have chronotypic problems. For this reason, we investigated a potential connection between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone. METHODS: Fifteen healthy students between 21 and 22 years of age were examined for physiological parameters of chronotypes based on melatonin and growth hormone secretion patterns, using a fluorescence enzyme immunoassay. Salivary samples were collected from subjects at home five times each day (20:00, 24:00, 04:00, 08:00, and 12:00 h). In addition, the subjects rated their psychosomatic symptoms twice (at 08:00 and 20:00 h). RESULTS: A group with irregular circadian rhythm of melatonin (ICR) showed more psychosomatic complaints than a group with the regular circadian rhythm (RCR), especially for anxiety. CONCLUSION: Psychosomatic symptoms, particularly anxiety, may be associated with irregularity in melatonin and growth hormone rhythms, which can be altered by basic lifestyle habits even in healthy students.