Preoperative hyperglycemia within 24 hours of surgery is associated with adverse outcomes after rotator cuff repair

Background: Rotator cuff repair (RCR) is a common orthopedic procedure that relies on proper tendon healing for good outcomes. While hyperglycemia is known to worsen outcomes in other surgeries, its effects on RCR remain underexplored. We investigated whether preoperative hyperglycemia is associated with increased complication rates following RCR using a large, multi-institutional database. Methods: Using the TriNetX Research Network, we identified patients who underwent primary RCR between May 2005 and May 2024. Patients were divided into two cohorts based on preoperative glucose within 24 hours of surgery: hyperglycemia (≥180 mg/dL) and normoglycemia (70–179 mg/dL). Patients without a recorded glucose value, or with hypoglycemia, prior shoulder fracture, prior RCR, or shoulder arthroplasty were excluded. Propensity score-matched cohorts were balanced for demographics, comorbidities, diabetes status, hemoglobin A1c (HbA1c), glucose-lowering medications, and surgical factors. Complications were assessed at 90 days and 1 year. P-values were adjusted using Benjamini-Hochberg false discovery rate correction. Results: The final matched cohorts comprised 5,839 patients per group. At 90 days, hyperglycemia was associated with significantly higher rates of sepsis, acute kidney injury, myocardial infarction, postoperative infection, and pain. At 1 year, hyperglycemic patients had higher rates of stress fracture and frozen shoulder. No differences were observed in revision surgery, shoulder replacement, or hardware removal between groups. Findings were largely consistent in a sensitivity analysis restricting the normoglycemic group to 70–139 mg/dL. Conclusions: Preoperative hyperglycemia is associated with higher short- and long-term complication rates following RCR. Elevated preoperative glucose appears to be an important factor influencing both systemic and musculoskeletal outcomes after RCR. Level of evidence: III.