Establishment of corticosterone immunoassay test and its correlation with stress parameters in shift workers

Aim: Aim of this thesis is validating corticosterone test for saliva and assess its association with stress parameters including cortisol, alpha-amylase, heart rate variability (HRV) and anxiety questionnaires in shift worker women. Additionally, effects of shift works on vital parameters, hematological parameters, some hormones and cytokine levels were also determined. Materials and Methods: Following validation of corticosterone test in the saliva, blood and saliva samples were taken and HRV was assessed (by 5 min electrocardiogram recording) in shift worker health care women personnel. In that regards, effects of whole or half-night shifts (Experiment I); alternating shift system (daytime-night, night-daytime, Experiment II) and long uninterrupted shift system (32 h, Experiment III) were investigated. Blood samples were used to analyze hematological parameters in addition to hormones (leptin, melatonin, estrogen, progesterone) and cytokines (TNF-alpha, IL-1beta and IL-6) while saliva samples were used to measure corticosterone, cortisol, alpha-amylase levels. All participants also filled in sleep and anxiety questionnaires and executed an attention test. Results: In shift worker women, it has been observed that stress parameters were influenced at varying levels depending on the type of shift (increased cortisol in Experiment I, increased corticosterone in Experiment II and increased HRV but decreased alpha-amylase in Experiment III); and that, in general, leucocyte ratio, cytokines (TNF-alpha, IL-1beta, IL-6), leptin and reproductive hormones were altered; and that sleep parameters were negatively influenced but vital parameters were not affected. There were significant positive correlations among the stress parameters. Sonuç: In addition to validation of salivary corticosterone test, it was revealed that shift types negatively affect the body and, that complex and interactive stress system operates differently depending on the types of shifts.