The Association Between Socioeconomic Position and Infection Risk After Hip Fracture Surgery: A Nationwide Cohort Study of 54,853 Patients.

PURPOSE: We examined the association between socioeconomic position (SEP) and risk of any infection after surgery for hip fracture, and whether markers of poor health modify this.

METHODS

Individual-level data on SEP markers (education, liquid assets, marital status, and cohabitation) were obtained from Danish registries for hip fracture patients undergoing surgery (2010-2018). We computed cumulative incidences of any hospital-treated infection within one month after surgery. Using Cox regression we estimated adjusted hazard ratios (aHRs) with 95% confidence intervals. Analyses were stratified by comorbidity clusters based on latent class analysis, body mass index (BMI), pre-fracture mobility, and residence type.

RESULTS

The incidences of infection were: 17% for low vs 16% for high education (aHR 1.10, 1.02-1.18), 19% for low vs 16% for high liquid assets (aHR 1.21, 1.15-1.28), 18% for divorced vs 16% for married (aHR 1.24, 1.15-1.32), and 18% for living alone vs 15% for cohabiting (aHR 1.16, 1.06-1.28). The incidence of infection was highest among patients with diabetic-renal comorbidity, underweight, poor mobility, or nursing home residency. The magnitude and direction of associations were modified by comorbidity clusters, BMI, mobility, and residence type.

CONCLUSION

We observed socioeconomic inequalities in 30-day risk of infection after hip fracture surgery. Health modified the observed inequalities but could not fully explain them.