Effect of Toxoplasmosis on Melatonin and Cortisol in Smoking Addiction

Abstract

Background: Toxoplasma gondii infection can cause changes in neurotransmitter levels in the brain, which can affect anindividual's behavior. Objectives: The aim of this study was to investigate the relationship between latent toxoplasmosis and cigarette addictionand its effect on cortisol and melatonin levels, which are known to be associated with nicotine addiction. Methods: The patient group consisted of 90 smokers who applied to the Alcohol and Substance Addiction Treatment andEducation Center Unit of the Health Sciences University Training and Research Hospital. Individuals with any substanceaddiction other than smoking were excluded from the study. The control group included 82 volunteers who had not used anysubstances in the last year. Toxoplasmagondii positivity, as well as cortisol and melatonin levels, were investigated via enzyme-linked immunosorbent assay of the serum samples taken from the study participants. The Z test and Fisher's exact test wereused to determine statistical significance at P < 0.05. The independent-samples Kruskal-Wallis t-test was used to determine therelationship between cortisol and melatonin levels and T.gondii positivity. Results:Toxoplasmagondii immunoglobulin G was detected in 52 (57.8%) of the smokers and 23 (28%) of those in the controlgroup. A statistically significant relationship was found between T.gondii positivity and smoking (P = 0.001). In the statisticalevaluation, no relationship was found between T.gondii positivity and cortisol and melatonin in smokers. Conclusions: There is an association between T.gondii infection and smoking addiction, but this association is independent ofmelatonin and cortisol levels.