Distinct Patterns of Conjoint Symptom Distress and Functional Impairment in the Last Year of Life Predict Terminally Ill Cancer Patients' Survival

Abstract

Context/ObjectivesOur study addressed important knowledge gaps about trajectories of distinct conjoint symptom-functional states, that is, patterns for different levels of combined symptom distress and functional impairment, over cancer patients' last year and their ability to predict survival. MethodsWe identified distinct symptom-functional states and explored their changes over 317 terminally ill cancer patients' last year by a transition model using hidden Markov modeling. These distinct symptom-functional states' ability to predict current survival probability, measured in the previous assessment, was evaluated by multivariate Cox regression models. ResultsWe identified five worsening, conjoint symptom-functional states: 1) mild symptom distress with high functioning, 2) moderate symptom distress with mild functional impairment, 3) severe symptom distress with moderate functional impairment, 4) moderate symptom distress with severe functional impairment, and 5) profound symptom distress and functional impairment. Trajectories of these five states differed substantially by direction (downward vs. upward) and speed. Participants in States 1–4 had substantially lower risk of subsequent death than those in State 5 (adjusted hazard ratios [95% CI] ranged from 0.048 [0.028–0.081] to 0.434 [0.316–0.579]). The risk of subsequent death differed significantly between patients in any two distinct symptom-functional states, except between those in States 3 and 4. ConclusionOur identification of five distinct symptom-functional states and their unique transition patterns and prediction of mortality provides all stakeholders with guides for end-of-life care. Goals of end-of-life care should change toward palliative care and effective symptom management for patients with at least moderate symptom distress and substantial functional impairment.