Patients with poorly controlled diabetes have an elevated risk of complications and death following total joint arthroplasty. Some centers set a threshold hemoglobin A1c (HbA1c) value above which surgery is delayed pending better glycemic control. The purpose of this study was to examine how many diabetic patients scheduled for primary total joint arthroplasty underwent a delay because of an HbA1c value of >7.0%, how many subsequently achieved this goal, and how much time was necessary to achieve this goal.
The study involved a retrospective chart review at one Veterans Affairs medical center. Patients with an HbA1c of >7.0% were referred to their primary care provider for better diabetic control. Unless reduction of the HbA1c to ≤7.0% was deemed medically inadvisable, surgery proceeded only after the patient returned with an HbA1c of ≤7.0%.
A total of 404 diabetic patients were scheduled for total joint arthroplasty. In fifty-nine cases, the surgery was delayed because of an HbA1c of >7.0%. Thirty-five of these patients were able to reduce the HbA1c level to ≤7.0% after a median of 141 days (range, seven to 1043 days), and twenty-four failed to achieve this goal. If an HbA1c goal of ≤8.0% had been used, the surgery would have been delayed in thirty cases, and twenty-one of these patients would have subsequently achieved the goal.
When establishing a goal designed to reduce perioperative risks, there should be an expectation that the goal is achievable. Overall, an HbA1c of ≤7.0% was achieved by 380 of the 404 diabetic patients (94%; 95% confidence interval [CI], 91% to 96%), but it was achieved by only thirty-five (59%; 95% CI, 46% to 72%) of the fifty-nine patients presenting with an HbA1c of >7.0%. An HbA1c of 8.0% was achieved by 395 (98%; 95% CI, 96% to 99%) of the diabetic patients and by twenty-one (70%; 95% CI, 50% to 85%) of the thirty patients presenting with an HbA1c of >8.0%. Achieving an HbA1c value of ≤7.0% may not be possible for certain diabetic patients, and such a requirement may risk access to total joint arthroplasty treatment.