Context/ObjectiveTemporal changes have not been examined in patient-caregiver agreement on life-sustaining treatment (LST) preferences at end of life (EOL). We explored the extent of and changes in patient-caregiver agreement on LST-preference patterns for two independent cohorts of Taiwanese cancer patient-family caregiver dyads recruited a decade apart. MethodsWe surveyed preferences for cardiopulmonary resuscitation, intensive care unit care, cardiac massage, intubation with mechanical ventilation, intravenous nutritional support, tube feeding, and dialysis among 1049 and 1901 dyads in 2003–2004 and 2011–2012, respectively. LST-preference patterns were examined by multi-group latent class analysis. Extent of patient-caregiver agreement on LST-preference patterns was determined by percentage agreement and kappa coefficients. ResultsFor both patients and family caregivers, we identified seven distinct LST-preference classes. Patient-caregiver agreement on LST-preference patterns was poor to fair across both study cohorts, indicated by 24.4%–43.5% agreement and kappa values of 0.06 (95% CI: 0.04, 0.09) to 0.27 (0.23, 0.30), and declined significantly over time. Agreement on LST-preference patterns was most likely when both patients and caregivers uniformly rejected LSTs. When patients disagreed with caregivers on LST-preference patterns, discrepancies were most likely when patients totally rejected LSTs but caregivers uniformly preferred LSTs or preferred nutritional support but rejected other treatments. ConclusionPatients and family caregivers had poor-to-fair agreement on LST-preference patterns, and agreement declined significantly over a decade. Encouraging an open dialogue between patients and their family caregivers about desired EOL care would facilitate patient-caregiver agreement on LST-preference patterns, thus honoring terminally ill cancer patients' wishes when they cannot make EOL-care decisions.