The association of acute and chronic somatic disease, depressive symptoms and neurotransmitter precursor monamine levels

• Published in: Journal of psychosomatic research Vol. 109; p. 108
• Main Authors: Hüfner, K., Fuchs, D., Blauth, M., Sperner-Unterweger, B.
• Format: Journal Article
• Language: English
• Published: London Elsevier Inc 01.06.2018; Elsevier Science Ltd
• Subjects: Amino acids; Antidepressants; Antipsychotics; Anxiety; C-reactive protein; Catabolites; Change agents; Comorbidity; Correlation analysis; Enzyme-linked immunosorbent assay; High-performance liquid chromatography; Hydroxylase; Inflammation; Inflammatory diseases; Injuries; Mental depression; Mental disorders; Mental health; Metabolites; Neopterin; Neurotransmitters; Orthopedic surgery; Orthopedics; Phenylalanine; Phenylalanine 4-monooxygenase; Serotonin; Serum; Severity; Somatic symptoms; Surgery; Symptoms; Trauma; Tryptophan
• ISSN: 0022-3999; 1879-1360
• DOI: 10.1016/j.jpsychores.2018.03.071

Aims: Somatic inflammatory conditions are known to influence neurotransmitter precursor amino acids, such changes can lead to depressive symptoms. Not much is known about the possible differences in acute and chronic somatic conditions. In this prospective study we investigated neurotransmitter precursor amino acids in serum of patients with acute and chronic somatic disease and evaluated their association with depressive symptoms. Methods: 177 subjects with and without chronic medical comorbidity (factor: chronic somatic disease) admitted to the trauma and orthopaedic surgery ward for an intervention (factor: acute somatic disease) were included in the analysis. Chronic medical comorbidity was scored using Carlson Index, trauma severity using Injury Severity Score and depressive and anxiety symptoms using the Hospital Anxiety and Depression Scale (HADS). C-reactive protein (CRP), neopterin, kynurenine/tryptophan and phenylalanine/tyrosine were analysed by HPLC or ELISA prior to surgery and at discharge. Mixed Model as well as correlation analyses were performed. Results: CRP and neopterin levels were influenced by the factors "acute somatic disease" (ps<0.001) and "chronic somatic disease" (p=0.041, p=0.001 respectively). The phenylalanine/tyrosine ratio (index of phenylalanine hydroxylase activity) was related to the factors "acute somatic disease" (p<0.001) and associated with "mental health-depression" (p=0.005), while kynurenine/tryptophan (index of the serotonin pathway) was influenced by "chronic somatic disease" (p=0.005). No significant effects of "mental health-anxiety" or interactions of these factors were found. Gender or the intake of antidepressants or antipsychotics had no effect. Differences in HADS depression values correlated with changes in phenylalanine/tyrosine levels. Conclusion: In conclusion, alterations in phenylalanine/tyrosine pathway were induced by acute somatic disease and related to depressive symptoms, while changes in kynurenine/tryptophan were associated with chronic somatic disease and possibly further downstream catabolites of the measured metabolites, not investigated here, are associated with mental health. The observed effects are probably mediated by inflammation associated with the somatic disease.