Objectives Among primary prevention-type adults not on lipid-lowering therapy, conflicting results exist on the relationship between low-density lipoprotein cholesterol (LDL-C) and long-term mortality. We evaluated this relationship in a real-world evidence population of adults. Design Retrospective cohort study. Setting Electronic medical record data for adults, from 4 January 2000 through 31 December 2022, were extracted from the University of Pittsburgh Medical Center healthcare system. Participants Adults without diabetes aged 50–89 years not on statin therapy at baseline or within 1 year and classified as primary prevention-type patients. To mitigate potential reverse causation, patients who died within 1 year or had baseline total cholesterol (T-C) ≤120 mg/dL or LDL-C <30 mg/dL were excluded. Main exposure measure Baseline LDL-C categories of 30–79, 80–99, 100–129, 130–159, 160–189 or ≥190 mg/dL. Main outcome measure All-cause mortality with follow-up starting 365 days after base