Factors associated with dysfunction of autogenous arteriovenous fistula in patients with secondary hyperparathyroidism after parathyroidectomy.

Background: Secondary hyperparathyroidism (SHPT) is a prevalent chronic complication in patients undergoing hemodialysis. Parathyroidectomy (PTX) is crucial for reducing mortality and improving the prognosis in the treatment of refractory hyperparathyroidism. However, it is often associated with a number of postoperative complications such as postoperative hypotension, hyperkalemia, and hungry bone syndrome. A previous study demonstrated that low blood pressure influences the patency of autogenous arteriovenous fistulas (AVF). Few studies have examined AVF dysfunction following PTX. This study aimed to identify and describe the risk variables associated with AVF dysfunction after PTX.

Methods: Cases of AVF dysfunction after PTX between 2015 and 2021 were studied. Four controls were identified for each patient and were matched for sex and age. Biochemical parameters and blood pressure of the patients before and after PTX were recorded. Risk factors for AVF dysfunction after PTX were identified using conditional logistic regression analysis.

Results: Sixteen patients and 64 controls were included in this study. Baseline demographic and laboratory data were compared. Patients in the AVF dysfunction group had lower levels of postoperative calcium than the controls. After surgery, calcium levels decreased more in patients with AVF dysfunction than in the control group. The decrease in systolic blood pressure (ΔSBP) after PTX was greater in the AVF dysfunction group than that in the control group. For each 1 mmHg increment in ΔSBP, the risk of AVF dysfunction after surgery increased by 11.6% (OR = 1.116, 95% CI, 1.005-1.239, p = .040). The likelihood of developing AVF dysfunction after surgery was twelvefold higher in diabetic patients than in non-diabetic patients (OR = 12.506, 95% CI, 1.113-140.492, p = .041). Among patients with ΔSBP > 5.8 mmHg after PTX, the AVF failure rate was significantly greater in patients with diabetes than in those without diabetes. Patients with a history of AVF failure had a nine-fold higher risk of developing AVF dysfunction (OR = 9.143, 95% CI, 1.151-72.627, p = .036). Serum albumin, hemoglobin, ΔiPTH, and age were not independent predictors of AVF dysfunction. The cutoff value for SBP was 5.8 mmHg, as determined by the Youden index of the receiver operating characteristic curve.

Conclusion: Decreased systolic blood pressure (ΔSBP) after PTX, diabetes, and AVF failure history were risk factors for AVF dysfunction following PTX in patients with SHPT. Diabetes patients with ΔSBP > 5.8 mmHg were more prone to AVF dysfunction after PTX.