UC Irvine

End-stage renal disease is a chronic, terminal condition in which the kidneys retain less than 5% of their normal capacity for filtering wastes and fluids from the bloodstream. Kidney failure represents a significant and costly public health problem, especially for Hispanic patients. While there are no known direct psychosocial causes of kidney failure, sociobehavioral factors play a crucial role in determining the capacity for survival for the end-stage renal disease patient; in addition to taking on dialysis treatment, in which an artificial kidney filters waste products from the body, patients must take dozens of medications and monitor and restrict their diet and fluid intake, resulting in high disease burden, high cognitive demand, and high risk for morbidity and mortality. Additionally, changes in cognitive and psychosocial functioning over the course of the dialytic cycle may be crucial in determining treatment outcomes for these patients. The purpose of the present study was to examine the interrelationships between cognitive functioning, general and disease-specific social support, and the length of the interdialytic interval on adherence to treatment in a sample of patients on hemodialysis. The study was the first to explore these relationships using a sophisticated electronic diary system.

Participants included 22 (female n = 11; Mean age 44 years) English- and Spanish-speaking, primarily Hispanic patients being treated for kidney failure at the UC Irvine Medical Center. Overall, levels of social support in this sample were high, and reports of cognitive dysfunction were minimal. Some aspects of social support, particularly diet-related support, were associated with improved adherence to treatment, but in general, support did not substantially influence engagement in behaviors of disease self-management. Additionally, contrary to hypotheses, cognitive functioning was greater over two-day interdialytic intervals than shorter one-day intervals, and was not found to mediate the relationship between length of the interdialytic interval and disease self-management. Likewise, the effect of cognitive functioning on treatment adherence was not buffered by social support. Such findings provide some limited support for an osmotic theory of cognitive dysfunction resulting from hemodialysis, but should interpreted with caution pending recruitment of a larger sample and a higher degree of compliance with the ecological momentary assessment protocol.