Predictors of patient treatment preferences and spouse substituted judgments: The case of dialysis continuation

Objectives. To examine the factors predicting preferences for continued hemodialysis treatment among patients with end-stage renal disease (ESRD) and to compare these factors to those predicting their spouses' predictions of patients' preferences (substituted judgments). Design. Descriptive, cross-sectional. Participants. Total of 291 hemodialysis patients, aged 55 years and older. and their spouses. Measurement. Hypothetical scenarios were designed to elicit preferences for dialysis continuation Under various health conditions. Other measures included the Philadelphia Geriatric Center Negative Affect Scale, Kidney Disease Symptoms Scale, Brief Multidimensional Measure of Religiousness, single-item global subjective health and quality-of-life measures, 2-item fear of end-of-life suffering measure, and selected demographics. Results. Patients' preferences and spouses' judgments were only moderately correlated (r = 0.33). Multiple regression analyses revealed that patients' preferences to continue dialysis were positively related to education, subjective quality of life, and religious participation and negatively related to months of ESRD treatment and fear of end-of-life suffering (R-2 = 0.15). Spouses' substituted judgments regarding patients' dialysis continuation preferences were positively related to African American race and spouses' perceptions of patients' quality of life and negatively related to months of ESRD treatment, spouses' perception of patients' negative affect, and spouses' own fear of end-of-life suffering. Conclusion. Patients and surrogates used different criteria in formulating judgments about continuation of life-sustaining treatment and had different perceptions about the patients' condition. Furthermore, the substituted judgments of Spouses were influenced by their own characteristics. These processes may explain inaccurate substituted judgments.