Universal Haemoglobin A1c screening reduce periprosthetic joint infection in primary total knee arthroplasty

Abstract

Introduction: Diabetes mellitus is an established modifiable risk factor for periprosthetic joint infection (PJI). Haemoglobin A1c (HbA1c) is a glycaemic marker that correlates with diabetic complications and PJI. As diabetes and pre-diabetes are frequently asymptomatic and increasing evidence to suggest linkage with osteoarthritis, it is reasonable to provide HbA1c screening before total knee arthroplasty (TKA). With HbA1c screening, we aimed to investigate the prevalence of undiagnosed dysglycaemia in TKA patients, and whether such practice can reduce PJI. Methods: All TKAs from March 2017 to May 2019 had HbA1c screening were reviewed. Pre-diabetes and diabetes were defined according to the American Diabetes Association. Patients with HbA1c ≥7.5% were referred to an endocrinologist for optimisation before TKA. The PJI rates were compared with histological control with no HbA1c screening. All PJIs were defined according to the Musculoskeletal Infection Society working group in 2011. Results: In total, 729 patients (934 TKAs) had HbA1c screening before TKA. Prevalence of known pre-diabetes and diabetes was 2.3% and 25.2%, respectively, while 36.4% and 1.6% had undiagnosed pre-diabetes and diabetes. We only needed to screen three patients during pre-TKA assessment to detect one patient with undiagnosed dysglycaemia. Periprosthetic joint infection rates were significantly lower in HbA1c screening TKAs (0.2% vs 1.0%, p=0.018). Conclusion: In all, 38% of patients scheduled for TKA had undiagnosed diabetes or pre-diabetes. Haemoglobin A1c screening before TKA provides a cost-effective opportunity to identify undiagnosed dysglycaemia. Universal HbA1c screening and optimisation before TKA was effective in reducing PJI.