Evaluating Advance Care Planning in Patients with a Glioma: A Systematic Review of Patient, Clinical, and Health Care Outcomes

Abstract Background Advance care planning (ACP) aims to align future care with people’s preferences and values. Timely ACP is crucial in patients with a glioma due to the progressive neurological decline, which affects health-related quality of life and decision-making capacity. Robust methods to evaluate ACP in patients with a glioma are lacking, and documentation alone has been shown to be an inadequate measure of successful ACP. This systematic review identifies and categorizes the outcomes reported in studies evaluating ACP in patients with a glioma. Methods A systematic literature search was conducted in six databases to identify articles published between January 1990 through May 2025. Data were extracted on study characteristics and reported outcomes. Outcomes were categorized into six domains: patient-reported outcomes, patient-reported experiences, structure, process, health care utilization, and clinical outcomes. Results Twenty-one studies met the inclusion criteria, reporting a total of 102 outcomes (median 5 [range 1-11]). Most outcomes reflected what was done in providing care and included advance directive documentation (process outcomes). No studies reported outcomes reflecting the organization of care (structure outcomes). Outcomes were obtained through questionnaires (n = 60/102, 59%), medical records (n = 39/102, 38%), or interviews (n = 2/102, 2%). Ten studies together reported 25 unique validated questionnaires, of which only three were used in multiple studies. Conclusions Studies evaluating ACP in patients with a glioma are highly heterogeneous and predominantly report process outcomes rather than outcomes aligned with the goals of ACP. Future research should prioritize person-centered outcomes to better capture the impact of ACP.