ORIGINAL ARTICLE BMD improvements after operation for primary hyperparathyroidism Lars Rolighed & Peter Vestergaard & Lene Heickendorff & Tanja Sikjaer & Lars Rejnmark & Leif Mosekilde & Peer Christiansen Received: 29 June 2012 / Accepted: 23 October 2012 / Published online: 7 November 2012 # Springer-Verlag Berlin Heidelberg 2012 Abstract Purpose This study aims to quantify bone mineral density (BMD) changes following surgery in patients with primary hyperparathyroidism (PHPT) and to assess their relationship with clinical and biochemical variables. Methods A historic cohort of 236 PHPT patients with DXA scans pre- and 1-year postoperatively, clinical data, and biochemical data was analyzed. Results The mean age was 60 years (range 19–86) and 81 % of the patients were women. A significant postoperative 2.6 % (95 % CI, 2.1; 3.1) increase in lumbar spine BMD was seen. The increase in BMD was positively associated with preoperative plasma PTH (p 0 0.002), Ca 2+ (p <0.001), and alkaline phosphatase (p 0 0.014). Hip BMD increased 1.5 % (1.1; 1.9). The increase in BMD was positively associated with preoperative plasma PTH (p 0 0.005) and Ca 2+ (p <0.001) and inversely associated with plasma creat- inine (p 0 0.004) and age (p 0 0.018). Total forearm BMD did not change significantly (-0.2 % (-0.5; 0.1)). An increase in forearm BMD was seen in 38 % of all patients, and the changes were positively associated with plasma PTH (p <0.001) and Ca 2+ (p 0 0.009). In all 91 patients with mild PHPT (plasma Ca 2+ <1.45 mmol/l), there was a significant postop- erative increase in spine BMD (1.9 % (1.2; 2.7)) and in hip BMD (1.0 % (0.4; 1.6)), but not in the forearm BMD (-0.3 % (-0.7; 0.2)). The postoperative BMD gain was higher in the hip and forearm in patients operated for adenomas compared with patients treated for hyperplasia. Conclusions We found significant postoperative BMD improvements both at the hip and the spine. BMD improve- ments were also significant in mild cases. At all scan sites, there were positive associations between preoperative plasma PTH levels and postoperative BMD increases. The measured BMD changes may mainly be due to a decrease in PTH- induced bone turnover with refilling of the remodeling space. Keywords Primary hyperparathyroidism . Surgery . PTH . BMD . Parathyroidectomy Introduction In primary hyperparathyroidism (PHPT), the choice be- tween surgery and medical follow-up relies primarily on symptoms, complications, biochemical variables, and bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) [1]. Notably, the management of patients with asymptomatic PHPT has been discussed wide- ly for several years, both in published articles [2, 3] and at three international workshops [1, 4, 5]. It is obvious that the definitive treatment of PHPT is parathyroidectomy (PTX) with excision of pathologic parathyroid glands [2]. After introduction of modern routine preoperative imaging tech- niques (SestaMIBI scintigraphy and ultrasound), PTX is often performed as a minimally invasive procedure with low morbidity and high cure rate [6]. However, apparently, This study was presented at the ESES Congress, Gothenburg on May 25–26, 2012. L. Rolighed (*) : P. Christiansen Department of Surgery P, Aarhus University Hospital, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark e-mail: larsrolighed@gmail.com P. Vestergaard : T. Sikjaer : L. Rejnmark : L. Mosekilde Department of Internal Medicine and Endocrinology MEA, Aarhus University Hospital, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark L. Heickendorff Department of Clinical Biochemistry, Aarhus University Hospital, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark Langenbecks Arch Surg (2013) 398:113–120 DOI 10.1007/s00423-012-1026-5