Pre-operative Cinacalcet Administration Reduces Immediate Post-operative Hypocalcemia Following Total Parathyroidectomy in Severe Renal Hyperparathyroidism

Abstract

<h3>Background</h3><p>In severe renal hyperparathyroidism (RHPT), whether administrating Cinacalcet before total parathyroidectomy can reduce post-operative hypocalcemia remains unclear. We compared post-operative calcium kinetics between those who took Cinacalcet before surgery (Group I) and those who did not (Group II).</p><h3>Methods</h3><p>Patients with severe RHPT (defined by PTH ≥ 100 pmol/L) who underwent total parathyroidectomy between 2012 and 2022 were analyzed. Standardized peri-operative protocol of calcium and vitamin D supplementation was followed. Blood tests were performed twice daily in the immediate post-operative period. Severe hypocalcemia was defined as serum albumin-adjusted calcium < 2.00 mmol/L.</p><h3>Results</h3><p>Among 159 patients who underwent parathyroidectomy, 82 patients were eligible for analysis (Group I, <em>n</em> = 27; Group II, <em>n</em> = 55). Demographics and PTH levels before Cinacalcet administration were comparable (Group I: 169 ± 49 pmol/L vs Group II: 154 ± 45, <em>p</em> = 0.209). Group I had significantly lower pre-operative PTH (77 ± 60 pmol/L vs 154 ± 45, <em>p</em> < 0.001), higher post-operative calcium (<em>p</em> < 0.05), and lower rate of severe hypocalcemia (33.3% vs 60.0%, <em>p</em> = 0.023). Longer duration of Cinacalcet use correlated with higher post-operative calcium levels (<em>p</em> < 0.05). Cinacalcet use for > 1 year resulted in fewer severe post-operative hypocalcemia than non-users (<em>p</em> = 0.022, OR 0.242, 95% CI 0.068–0.859). Higher pre-operative ALP independently correlated with severe post-operative hypocalcemia (OR 3.01, 95% CI 1.17–7.77, <em>p</em> = 0.022).</p><h3>Conclusion</h3><p>In severe RHPT, Cinacalcet led to significant drop in pre-operative PTH, higher post-operative calcium levels, and less frequent severe hypocalcemia. Longer duration of Cinacalcet use correlated with higher post-operative calcium levels, and the use of Cinacalcet for > 1 year reduced severe post-operative hypocalcemia.<br></p>