Postoperative risks of type 2 diabetes in elderly hip fracture patients: a propensity score-matched study.

Introduction: Type 2 diabetes is associated with an increased risk of fragility fractures, even in individuals with normal or high bone mineral density. However, the impact of type 2 diabetes on postoperative outcomes after hip fracture surgery in elderly Japanese patients remains unclear. This study evaluated the association between type 2 diabetes and postoperative complications, including in-hospital mortality, using a nationwide database in Japan.

Materials and methods: A retrospective cohort study was conducted using the Diagnosis Procedure Combination (DPC) database from April 2016 to March 2022. Patients aged ≥ 65 years who underwent hip fracture surgery were included. Propensity score matching (1:1) was performed to adjust for confounders. Logistic regression analyses were used to assess associations between type 2 diabetes and outcomes.

Results: Of the 474,293 eligible patients included in this study, 18.5% were identified as having comorbid type 2 diabetes. Following 1:1 propensity score matching, the final analytic cohorts each comprised 83,283 patients. Although statistically significant, the presence of type 2 diabetes was associated with only modest increases in the risks of postoperative myocardial infarction (risk difference [RD]: 0.0007), cognitive dysfunction (RD: 0.0029), and in-hospital mortality (RD: 0.0045), with all comparisons yielding p-values of less than 0.0001. Additionally, the length of hospital stay was longer among patients with type 2 diabetes.

Conclusions: Although the absolute risk differences were small, type 2 diabetes remains an independent risk factor for adverse postoperative outcomes following hip fracture surgery in elderly Japanese patients. Tailored perioperative strategies may help optimize outcomes in this vulnerable population.