1b - Disparity in surgical site infection risk according to ethnicity and Index of Multiple Deprivation in England, Jan 2010 – Dec 2019.

Background : The role of ethnicity and socio-economic status in surgical outcomes has been implicated in several studies. The UK Health Security Agency (UKHSA) SSI Surveillance Service (SSISS) data from National Health Service (NHS) hospitals in England were used to assess the evidence for differential risk of surgical site infection (SSI).

Methods : SSISS data following hip replacement, knee replacement, large bowel, breast, coronary artery bypass graft (CABG) and cardiac (non-CABG) surgery between 2010 and 2019 were matched to Hospital Episode Statistics (HES) on NHS number to ascertain patient ethnicity and Index of Multiple Deprivation (IMD). Patients were prospectively followed up for up to 30 days or 1 year (if an implant is used) to detect inpatient and re-admission SSIs based on international standard case definitions. Multivariable logistic regression analyses were carried out to investigate association between the risk of SSI and ethnicity and IMD (white ethnicity being the reference group) adjusting for patient and surgery related risk factors.

Results : Ethnicity and IMD data were available for 87.4% and 86.1% of 972,422 SSISS records, respectively. Patients with mixed ethnicity had increased adjusted odds of SSI following large bowel (aOR=2.04; 95%CI: 1.10-3.76) and breast surgery (aOR=4.53; 1.04-19.78); no significant difference in SSI risk was observed for other groups of ethnicity nor other surgical categories.Living in most deprived areas (IMD decile 1) was associated with increased adjusted odds of infection in breast surgery versus IMD 10 (aOR=3.78; 1.37-10.41). A crude association was observed in hip and knee replacement and cardiac (non-CABG) surgery; however these associations did not persist after adjustment.

Conclusions : These preliminary results provide suggestive evidence of the association between social determinants of health and SSI risk in some surgical categories.