ObjectiveThis study aimed to examine group-based trajectories of hospital service use by people with chronic kidney disease (CKD) in the last 12months of life.MethodsA retrospective cohort study was conducted using hospital admission and mortality data in New South Wales, Australia. Individuals aged ≥18years who were hospitalised during 2014-2021 and who died during 2015-2021 were included. A group-based trajectory analysis was conducted including all-cause admissions and unplanned-only admissions. Multinomial logistic regression examined predictors of trajectory group membership.ResultsThere were 10,653 adults who had at least one CKD hospital admission 12months prior to death. Four group-based trajectories of hospital service use were identified for all-cause admissions (i.e. Very-Low, Low, Moderate, High) and three group-based trajectories for unplanned-only admissions (i.e. Low, Moderate, High). The study identified associations between frequent hospitalisations and key patient characteristics and health conditions. Individuals in the High hospitalisation group were more likely to have cancer (OR 4.55; 95% CI: 2.54-8.16). Additionally, the High unplanned hospitalisation group showed increased likelihoods of being adults aged 18-64years (OR 1.94; 95% CI: 1.32-2.84) and having diagnosis of congestive heart failure (OR 1.80; 95% CI: 1.26-2.55), cancer (OR 2.25; 95% CI: 1.49-3.40), mental disorders (OR 1.88; 95% CI: 1.35-2.62) or smoking (OR 2.01; 95% CI: 1.49-2.70) compared with the Low hospitalisation group.ConclusionsGroup-based trajectory analysis revealed specific patterns in hospital service usage. Understanding these patterns helps in devising targeted strategies to decrease unplanned hospitalisations among these high-risk patients.