Determination of Appropriate Sampling Time for Job Stress Assessment: the Salivary Chromogranin A and Cortisol in Adult Females / 예방의학회지

ABSTRACT

OBJECTIVES: This study was conducted to determine the appropriate sampling time of the salivary stress markers, chromogranin A (CgA) and cortisol as objective indices of job stress assessment in adult females. METHODS: The subjects were 20~39-year-old women (13 office workers, 11 sales-service workers, and 11 college students) who were eligible for the study and free of acute and chronic medical conditions. Salivary CgA and cortisol levels were determined by enzyme-linked immunosorbent assay (ELISA). Saliva samples were collected (2ml each) at 700, 800, 1030, 1200, 1730, and 2230 on a typical day. Salivary CgA and cortisol levels, according to sampling time, were compared among the three groups using general linear model. The full version of the Korean Occupational Stress Scale (KOSS), which includes socioeconomic characteristics, health behavior, work-related characteristics, and BMI, was used to access the subjects' job stress. Multiple regression analysis of the job stressors identified by the KOSS was performed on salivary CgA and cortisol levels. RESULTS: The salivary CgA level peaked at 700 (time of awakening), then decreased and were maintained at a low level throughout the day, and increased slightly at 1730. The salivary cortisol level increased steeply within the 1st hour after awakening, followed by a gradual decrease by 1200, and was then maintained at a low level throughout the day. The salivary cortisol levels of subjects who worked < or =5 days per week and graduated from the university were significantly lower at 800 (p=0.006). The salivary cortisol levels of non-smokers were significantly lower at 700 (p=0.040) and 800 (p=0.003) compared to smokers. There were no significant differences in salivary CgA and cortisol levels at 1030 and 1200 in general characteristics. The regression coefficients on salivary CgA level were significant with interpersonal conflict at 1730 and job insecurity at 2230. Regression coefficients on salivary cortisol level were significant with organizational system and total job stressors at 1730. CONCLUSIONS: We suggest that the appropriate sampling times for the salivary stress markers, CgA and cortisol, are at 700 (time of awakening), 800 (1 hour after awakening), 1730 (early evening), and 2230 (before sleep).