Participants were originally included during admission for acute hip fracture (October 2013-June 2015) at Sahlgrenska University Hospital, Mölndal, Sweden, and underwent lumbar CSF sampling at spinal anesthesia induction. Cognitive status prior to the fracture was assessed using CDR. Mortality will be ascertained through Swedish national registries. The follow-up extends survival assessment to approximately 10 years after surgery. Analyses will compare survival across baseline cognitive status categories and biomarker-defined groups (e.g., normal vs abnormal Aβ42/Aβ40 ratio), and may adjust for baseline covariates (e.g., age, sex, ASA class / hip fracture risk scores if available from original dataset).