Revisiting the Palliative Performance Scale: Change in scores during disease trajectory predicts survival

Background: The Palliative Performance Scale (PPS) on admission is a predictor of survival. However, it is not highly discriminating for mid-range scores. 'PPS Change' between two time points considers the disease trajectory, and may improve the scale's utility. Aim: The aim of this study is to determine if a change in PPS scores between two significant time points predicts survival. Design: This prospective cohort study examined 'Change on Admission', 'Change at Week 1', and 'Change at Week 2'. We followed patients until death or 6 months, whichever was earlier. Cox regressions were used to determine if the Change scores were predictors of survival, adjusting for age, sex, diagnosis category, Charlson Index, and Do-Not-Resuscitate order. Setting/Participants: The sample consisted of patients referred to the palliative care service. Results: All three Change scores were independent predictors of survival. The greater the change, the poorer the prognosis. At week 1, when compared to 'PPS Change <= 10%', 'Change 11% -30%' and 'Change > 30%' increased the hazard ratios by 1.70 (95% CI 1.10-2.63) and 3.14 (95% CI 1.77-5.59), respectively. At week 2, when compared to 'PPS Change <= 10%', 'Change 11% -30%' and 'Change > 30%' increased the hazard ratios by almost 3- and 8-fold, respectively. The same magnitude of Change scores also has higher hazard ratios as patients' hospitalization progressed. Conclusions: The magnitude of change in PPS score during the disease trajectory is associated with one's survival and is a potentially useful prognostication tool. Further research is needed to extend on our work.