Association between preoperative persistent hyperglycemia and postoperative length of hospital in geriatric hip fracture patients

TL;DR

High blood sugar before hip surgery in elderly patients is linked to longer hospital stays, with a 12% increased risk for each unit increase in glucose.

Contribution

This study identifies a dose-response relationship between preoperative hyperglycemia and prolonged hospitalization in geriatric hip fracture patients.

Findings

Persistent preoperative hyperglycemia is significantly associated with prolonged hospital length of stay.

Each 1 mmol/L increase in glucose raises the risk of longer hospitalization by 12%.

The association is stronger in females and patients with diabetes.

Abstract

Metabolic disorders play a significant role in determining the length of hospital stay following hip fracture surgery in elderly patients. Therefore, it is crucial to conduct an in-depth investigation into the relationship between stress-induced hyperglycemia—one of the manifestations of metabolic disorders—and hospitalization duration in this patient population.

This retrospective cohort study analyzed medical records of patients who underwent hip fracture surgery at a tertiary medical institution between January 2017 and November 2024. LASSO regression identified covariates for multivariate logistic regression. Propensity score matching minimized bias. Standardized mean differences assessed group balance. Logistic regression, restricted cubic splines, and dose-response analyses examined associations between blood glucose levels and LOS. Subgroup and threshold analyses evaluated robustness.

A total of 1,279 patients were included, with 673 (52.6%) having persistent preoperative hyperglycemia. The mean age was 74.7 ± 9.6 years, with 39.7% male and 60.3% female. Persistent hyperglycemia was significantly associated with prolonged LOS. Multivariate logistic regression showed a 12% increase in LOS for each unit increase in preoperative glucose (OR = 1.12, 95% CI: 1.07–1.18). Propensity score matching confirmed this association, with a significant linear trend (P < 0.001). Subgroup analyses revealed interactions with gender, hypertension, cerebrovascular disease, and diabetes mellitus.

Preoperative blood glucose levels are significantly associated with prolonged LOS in elderly hip fracture patients, showing a nonlinear dose-response relationship. Each 1 mmol/L increase in glucose raises LOS risk by 12%, with stronger correlations in females and diabetics. Timely intervention is critical above 6.16 mmol/L.

The online version contains supplementary material available at 10.1186/s12877-025-06116-z.

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