Poster 222. Hyperlipidemia Increases the Risk of Secondary Procedures in Patients Undergoing Arthroscopic Rotator Cuff Repair: A Database Study of 144,555 Patients

Objective: Hyperlipidemia (HLD) has been implicated as a potential risk factor for impaired tendon-to-bone healing after arthroscopic rotator cuff repair (RCR). Statin therapy may attenuate this risk, but findings remain inconsistent. Large-scale population data also suggest an increased incidence of rotator cuff disease in hyperlipidemic patients, with possible protective effects of statins. Given this conflicting evidence and the multifactorial nature of cuff healing, further investigation in large, diverse patient populations is warranted. It was hypothesized that HLD will be associated with higher rates of both repeat RCR and total shoulder arthroplasty. Methods: We conducted a retrospective cohort study using the TriNetX Research Network, a federated, de-identified electronic health record database comprising over 120 million patients from multiple healthcare organizations. Adults undergoing primary arthroscopic rotator cuff repair between October 1, 2015, and August 1, 2020, were identified using CPT code 29827. Patients were categorized into three cohorts: (1) no diagnosis of hyperlipidemia, (2) hyperlipidemia without perioperative statin use, and (3) hyperlipidemia with perioperative statin use. Hyperlipidemia was defined by ICD-10 codes E78.* within 12 months prior to surgery. Perioperative statin use was defined as an active prescription from 90 days before to 90 days after surgery. A separate analysis was run comparing groups based on total cholesterol and LDL levels. The primary outcome was subsequent rotator cuff repair identified by CPT 29827. Secondary outcomes included arthroscopic debridement for cuff pathology, conversion to total shoulder arthroplasty, repeat rotator cuff repair, removal of foreign body, lysis of adhesions, and manipulation under anesthesia. Outcomes were assessed at 6 months, 1 year, 2 years, and 5 years postoperatively. Propensity score matching (1:1 nearest neighbor, caliper 0.1) was performed between cohorts on demographics, comorbidities, and surgical factors. Risk ratios (RR) with 95% confidence intervals (CI) were calculated, and Kaplan-Meier survival analysis with log-rank testing was used for time-to-event comparisons. Significance was set at p < 0.05. Results: Following propensity matching, there were 40,430 patients in the HLD and control groups. Across 6-month to 5-year follow-up, patients with HLD had higher risks of repeat rotator cuff repair (RCR) and shoulder debridement at all time points (p < 0.05), with additional increased risks for lysis of adhesions (LOA) at 1 (p = 0.049), 3 (p = 0.030), and 5 (p = 0.008) years, arthroplasty at 3 (p = 0.024) and 5 (p < 0.001) years, and removal of foreign implant/body at 5 (p = 0.012) years. Cholesterol category comparisons (<200 vs. 200-239 or >240 mg/dl) showed no significant differences in complications, except for higher manipulation under anesthesia (MUA) risk in the 200-239 mg/dl group (p = 0.016). Among patients with low cholesterol, statin use was associated with increased 3-year risks of repeat RCR (p = 0.014) and arthroplasty (p = 0.008). LDL category comparisons revealed no differences for <100 vs. >=160 mg/dl, while <100 mg/dl vs. 100-160 mg/dl showed mixed findings, including lower repeat RCR risk at 3 years (p = 0.027) but higher arthroplasty risk at 5 years in the low LDL group (p = 0.015). Conclusions: Hyperlipidemia was consistently associated with higher rates of revision RCR, conversion to total shoulder arthroplasty, and select secondary procedures up to 5 years after surgery. Cholesterol and LDL levels alone were not reliable predictors, and even patients with low cholesterol on statins showed elevated risks, highlighting the complexity of lipid metabolism in tendon healing. These findings suggest that lipid status and statin use may significantly influence postoperative outcomes after RCR and should be considered in perioperative risk management and patient counseling. Given the high prevalence of hyperlipidemia and the mixed evidence on statin effects, further studies are needed to clarify the biological impact of dyslipidemia on tendon-to-bone healing.