Association of perceived stress and coping strategies with the renal function in middle-aged and older Japanese men and women

Elucidating the risk factors for chronic kidney disease is important for preventing end-stage renal disease and reducing mortality. However, little is known about the roles of psychosocial stress and stress coping behaviors in deterioration of the renal function, as measured by the estimated glomerular filtration rate (eGFR). This cross-sectional study of middle-aged and older Japanese men (n = 31,703) and women (n = 38,939) investigated whether perceived stress and coping strategies (emotional expression, emotional support seeking, positive reappraisal, problem solving, and disengagement) were related to the eGFR, with mutual interactions. In multiple linear regression analyses adjusted for age, area, lifestyle factors, and psychosocial variables, we found a significant inverse association between perceived stress and the eGFR in men (P(trend) = 0.02), but not women. This male-specific inverse association was slightly attenuated after adjustment for the history of hypertension and diabetes and was more evident in lower levels of emotional expression (P(interaction) = 0.003). Unexpectedly, problem solving in men (P(trend) < 0.001) and positive reappraisal in women (P(trend) = 0.002) also showed an inverse association with the eGFR. Perceived stress may affect the eGFR, partly through the development of hypertension and diabetes. The unexpected findings regarding coping strategies require the clarification of the underlying mechanisms, including the hormonal and immunological aspects.