Concentrations of sodium, potassium and cortisol in saliva, and self-reported chronic work stress factors

One hundred and fifteen electronics factory employees completed questionnaires relevant to work stress, and gave unstimulated saliva samples. As previously found, Perceived Coping Incapacity correlated very significantly with self-reported emotional upset and psychosomatic complaints. Salivary [Na+] correlated significantly with Perceived Coping Incapacity (rho = -0.30, p < 0.01), and also with emotional upset (rho = -0.19, p < 0.05). Raised [K+] tended to be associated with reduced fatigue (rho = -0.21, p < 0.05) and lower self-medication (rho = -0.21, p < 0.05) together with a greater perceived personal work responsibility (rho = 0.19, p < 0.05)-all consistent with the perception of work demands as positive challenges rather than stressors. Self-reported fatigue and emotional upset at work gave higher correlations with [K+] and [Na+] than either did on its own. Salivary [cortisol] was uncorrelated with self-reported work stress indices, and with [K+] and [Na+].