Predicting 12-Month Mortality for Peritoneal Dialysis Patients Using the “Surprise” Question

BACKGROUND: Studies in hemodialysis patients suggest that the "surprise" question can help to identify a group of patients with a high mortality risk who should receive priority for palliative care interventions. However, the same instrument has not been tested in peritoneal dialysis (PD) patients. METHOD: We studied 367 prevalent PD patients from a single dialysis center. Three clinicians independently answered the "surprise" question (Would I be surprised if this patient died within the next 12 months?) according to their clinical impression of the individual patient. Patients are then classified into "yes" (yes, surprised) and "no" (no, not surprised) groups. All patients were followed for 12 months. RESULTS: In this cohort, 109 patients (29.7%) were allocated to the "no" group, and 258 (70.3%), to the "yes" group. Patients in the "no" group were older and had high prevalences of pre-existing ischemic heart disease, cerebrovascular disease, and peripheral vascular disease. The "no" group had a higher score on the Charlson comorbidity index and a higher malnutrition-inflammation score. At 12 months, 44 patients had died. Mortality was 24.8% in the "no" group and 6.6% in the "yes" group. Multivariate analysis showed that an opinion of "Not surprised if dies in the next 12 months" was an independent predictor of 12-month mortality, with an associated 3.594 excess mortality risk (95% confidence interval: 1.411 to 9.151; p = 0.007). The positive predictive value of this opinion was 24.8%, and its negative predictive value was 93.4%. CONCLUSIONS: The "surprise" question has the potential to help identify a group of PD patients with high short-term mortality. Its use may contribute to a decision to refer PD patients for early palliative care assessment.