Abstract: Objective To evaluate the effect of parathyroidectomy (PTX) on blood pressure in maintenance hemodialysis (MHD) patients, to understand the correlation between serum calcium and blood pressure, and to compare the incidence of intradialytic hypotension before and after PTX. Methods A total of 31 MHD patients treated with PTX due to secondary hyperparathyroidism (SHPT) were enrolled in this study. Laboratory parameters, predialytic and intradialytic blood pressure, and the incidence of intradialytic hypotension were compared before and after PTX. The correlation between blood pressure difference and serum calcium difference before and after PTX was analyzed. Results Systolic blood pressure (SBP) after PTX for 1, 2, 4 and 8 weeks was significantly lower than that before operation in a week (156.81±28.27 mmHg; LSD-t=5.992, P<0.001 after PTX for one week; LSD-t=6.621, P<0.001 after PTX for 2 weeks; LSD-t=7.318, P<0.001 after PTX for 4 weeks; LSD-t=9.210, P<0.001 after PTX for 8 weeks). SBP decreased gradually after PTX and to the nadir after PTX for 8 weeks (117.37±12.16 mmHg). There was significant difference in SBP after PTX for one week (130.38±16.65 mmHg) and that after PTX for 8 weeks (LSD-t=3.268, P=0.002). Diastolic blood pressure (DBP) after PTX for 4 and 8 weeks was significantly lower than that after PTX for one week (LSD-t=4.046, P=0.002 after PTX for 4 weeks; LSD-t=6.421, P<0.001 after PTX for 8 weeks). DBP decreased to the nadir after PTX for 8th weeks (67.52±8.38 mmHg). There was significant difference in DBP after PTX for one week (79.83±11.17 mmHg) and that after PTX for 8 weeks (LSD-t=4.678, P＜0.001). The in-cidence of hypotension was 1.8% in the 558 hemodialysis sessions in the 6 weeks before PTX, and the incidence was 8.6% in the 558 hemodialysis sessions in the 6 weeks after PTX (χ2=26.260, P<0.001). The change of serum calcium was positively correlated with the change of SBP before and after PTX (r=0.630, P=0.006). The change of serum calcium was also positively correlated with the change of DBP but without statistical significance (r=0.331, P=0.070). Conclusion PTX effectively ameliorates SHPT with the decrease of iPTH, serum calcium, serum phosphorus, and blood pressure in MHD patients. SBP decreased more than DBP after PTX. The decrease of SBP was positively correlated with the decrease of serum calcium. However, the incidence of intradialytic hypotension increased after PTX.

Key words: Parathyroidectomy, Blood pressure, Hemodialysis, serum calcium