Readmission and Cost of Parathyroidectomy By Admission Status in Secondary Hyperparathyroidism

Key Points Among patients with kidney failure treated with dialysis, 37% underwent parathyroidectomy in the outpatient setting. Significant differences exist between patients selected for inpatient versus outpatient parathyroidectomy. Risk-adjusted readmission rates are similar after inpatient or outpatient parathyroidectomy for secondary hyperparathyroidism. Background Outpatient parathyroidectomy for secondary hyperparathyroidism of kidney disease is increasing. Reduced length of stay is often associated with higher rates of readmission. The safety of outpatient parathyroidectomy in this population must be evaluated given the morbidity and higher risk of post-parathyroidectomy hungry bone syndrome associated with kidney failure. In this study, we compare parathyroidectomy outcomes and costs by admission status in dialysis-dependent patients with secondary hyperparathyroidism. Methods Adult patients on dialysis who underwent elective parathyroidectomy for secondary hyperparathyroidism were identified in the Healthcare Cost and Utilization Project State Inpatient and State Ambulatory Surgery Databases from five geographically diverse states (2013–2019). Patients were classified by admission status: inpatient and outpatient (overnight or same-day). The primary outcome was 30-day readmission. Secondary outcomes were parathyroidectomy-related complications and cost. Outcomes were compared by admission status using chi-squared tests and costs using median quantile regression. Balancing weights were used for adjustment. Forward selection with logistic regression was used to identify factors associated with readmission among outpatients. Results Among 1267 study participants, 63% were inpatients. Among outpatients, 40% underwent overnight stay and 42% underwent same-day discharge. Inpatients were more likely to be younger, Black race, have nonprivate insurance, and increased comorbidities than outpatients ( P < 0.05). Overall readmission rate was 19%. Readmission was higher among inpatients (Inpatient: 22% versus Outpatient: 15%; P = 0.002). After balancing weights, adjusted 30-day readmission rate was similar between inpatients and outpatients (14% versus 15%; P = 0.79). Readmission was similar between overnight stay and same-day discharge (Unadjusted: 12% versus 15%; P = 0.47. Adjusted: 15% versus 15%; P = 0.97). Outpatients with parathyroid autotransplantation, anxiety disorder, autoimmune conditions, congestive heart failure, and moderate/severe liver failure had significantly increased odds of readmission after parathyroidectomy. Adjusted median costs varied significantly (Adjusted Inpatient: $9615 [Interquartile range (IQR), $6463–12,963] versus Outpatient: $6357 [IQR, $4966–8153]; P < 0.001; Adjusted Overnight: $6453 [IQR, $5551–7850] versus Same-day: $5526 [IQR, $4346–7187]; P < 0.001). Conclusions Select patients with secondary hyperparathyroidism may undergo outpatient parathyroidectomy safely with reduced costs.