Copyright © AE&M all rights reserved. 394 original article Arch Endocrinol Metab. 2019;63/4 Prediction of bone mass changes after successful parathyroidectomy using biochemical markers of bone metabolism in primary hyperparathyroidism: is it clinically useful? Monique Nakayama Ohe 1 https://orcid.org/0000-0003-4900-7185 Teresa Cristina Piscitelli Bonanséa 1 Rodrigo Oliveira Santos 2 Murilo Catafesta das Neves 2 https://orcid.org/0000-0002-8094-6298 Livia Marcela Santos 1 Marcello Rosano 2 https://orcid.org/0000-0002-3026-466X Ilda Sizue Kunii 1 Marise Lazaretti Castro 1 https://orcid.org/0000-0001-9186-2834 José Gilberto Henriques Vieira 1 ABSTRACT Objective: To measure type 1 serum amino-terminal propeptide procollagen (P1NP) and type 1 cross-linked C-terminal telopeptide collagen (CTX) before parathyroidectomy (PTX) in PHPT patients, correlating these measurements with bone mineral density (BMD) changes. Subjects and methods: 31 primary hyperparathyroidism (HPTP) were followed from diagnosis up to 12-18 months after surgery. Serum levels of calcium, parathyroid hormone (PTH) vitamin D, CTX, P1NP, and BMD were measured before and 1 year after surgery. Results: One year after PTX, the mean BMD increased by 8.6%, 5.5%, 5.5%, and 2.2% in the lumbar spine, femoral neck (FN), total hip (TH), and distal third of the nondominant radius (R33%), respectively. There was a significant correlation between BMD change 1 year after the PTX and CTX (L1-L4: r = 0.614, p < 0.0003; FN: r = 0.497, p < 0.0051; TH: r = 0.595, p < 0.0005; R33%: r = 0.364, p < 0.043) and P1NP (L1-L4: r = 0,687, p < 0,0001; FN: r = 0,533, p < 0,0024; TH: r = 0,642, p < 0,0001; R33%: r = 0,467, p < 0,0079) preoperative levels. The increase in 25(OH)D levels has no correlation with BMD increase (r = -0.135; p = 0.4816). On linear regression, a minimum preoperative CTX value of 0.331 ng/mL or P1NP of 37.9 ng/mL was associated with a minimum 4% increase in L1-L4 BMD. In TH, minimum preoperative values of 0.684 ng/mL for CTX and 76.0 ng/ mL for P1NP were associated with a ≥ 4% increase in BMD. Conclusion: PHPT patients presented a significant correlation between preoperative levels of turnover markers and BMD improvement 1 year after PTX. Arch Endocrinol Metab. 2019;63(4):394-401 Keywords Biochemical markers of bone turnover; parathyroid-related disorders; DXA; PTH; osteoporosis Correspondence to: Teresa Cristina Piscitelli Bonanséa Rua Borges Lagoa, 800 04032001 – São Paulo, SP, Brasil tebonanse@hotmail.com Received on Jan/15/2017 Accepted on Nov/8/2017 DOI: 10.20945/2359-3997000000154 1 Departamento de Endocrinologia e Metabolismo, Escola Paulista de Medicina, Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brasil 2 Departamento de Otorrinolaringologia, Cabeça e Pescoço, EPM-Unifesp, São Paulo, SP, Brasil