The study design was a retrospective cross-sectional observational cohort study. The study was performed at Uppsala University Hospital, which is an academic care center serving a primary population of approximately 300 000 people with 59 151 patient admissions per year. Serum glucose levels are analyzed as part of routine hospital procedures and stored in the database of the biochemical laboratory at Uppsala University Hospital. The study was approved by the central ethics committee in Sweden, and the need for informed consent was waived.