Influence of vitamin D deficiency on theelevated level of parathyroid hormone after surgical treatment of primary hyperparathyroidism in patients with mild disease

Abstract

Purpose – to determine the effect of vitamin D deficiency on the dynamics of parathyroid hormone (PTH) concentration after successful surgical treatment of patients with mild primary hyperparathyroidism (PHPT).Materials and methods. Postoperative laboratory data were analyzed in 169 patients with mild PHPT (without substantial damage to target organs), operated within 2010–2012. Serum levels of PTH, ionized calcium and vitamin D were analyzed in 1, 3, 6, 12 months after parathyroidectomy. Depending on the correction of vitamin D deficiency, which was held by cholecalciferol, patients were divided into 2 groups: 1st – retrospective (113 patients, operated in 2010–2011 without correction of vitamin D), including subgroup with vitamin D deficiency (87 persons; 77%) and those without vitamin D deficiency (26 persons; 33%); 2nd group – prospective (56 patients with PHPT and deficiency of vitamin D, operated during 2012), which were treated with vitamin D, starting 2–3 months before and 6 months after surgery.Results and discussion. In all cases, after the surgery, we observed normalization of PTH and calcium within the first 1–2 days. The level of PTH increased after 1-6 weeks after surgery and remained elevated for 3–12 months after surgery 73 (83.9%) patients with a retrospective of vitamin D deficiency and 4 (15.3%) patients without retrospective of deficiency of vitamin D. Treatment of vitamin D deficiency in 1st group with cholecalciferol and calcium was effective for PTH normalization in the postoperative period in 82 (94.3%) patients and 19 (73%) respectively. Symptomatic hypocalcemia was observed in 55 (63.2%) patients with vitamin D deficiency and in 11 (42.3%) patients without deficiency of vitamin D. All patients of prospective group (56 people) with mild PHPT and vitamin D deficiency cholecalciferol starting 2-3 months before surgery and till 6 months after surgery. After 1 month after surgery elevated levels of PTH was observed only in 8 (14.3%) patients. Symptomatic hypocalcemia was observed only in 13 (23.2%) patients, that is significantly less than among both retrospective groups (p<0.05).Conclusions. In patients with PHPT correction of vitamin D deficiency with cholecalciferol, starting 2–3 months before surgery can not only differentiate primary and secondary hyperparathyroidism, but also contribute to more rapid rehabilitation of patients after surgery and avoid prolonged increase of PTH in the postoperative period in most patients.