Potential utility of high preoperative levels of serum type I collagen markers in postmenopausal women with primary hyperparathyroidism with respect to their short-term variations after parathyroidectomy.

We evaluated short-term changes in serum amino-terminal procollagen propeptide (P1NP) and cross-linked C-terminal telopeptide (betaCTX) of type I collagen after parathyroidectomy (PTX) in 41 postmenopausal women with primary hyperparathyroidism (PHPT). Serum levels of 25-hydroxyvitamin D, intact PTH, calcium, phosphate, albumin, creatinine, P1NP, and betaCTX were measured before and 2 days after PTX. Their P1NP and betaCTX levels were compared with those measured in 41 normally menstruating and 30 postmenopausal controls. Fifteen of these 41 women had both pre-surgery P1NP and betaCTX concentrations above the upper limit noted in our postmenopausal controls [high turnover (HT) subgroup], while betaCTX levels were solely above the upper limit lastly mentioned in 11 women [high bone resorption (HBR) subgroup]. In addition, these two markers were within the postmenopausal control range in 12 of them [normal turnover (NT) subgroup]. A more significant decrease in postoperative betaCTX levels was observed in the 15 HT compared with the 12 NT PHPT women. The significant postoperative increase in P1NP levels observed in the 15 HT as well as in the 11 HBR was no longer significant in the 12 NT women. In conclusion, higher pre-surgery P1NP and betaCTX levels in post-menopausal PHPT women are associated with a preferential activation of bone formation over bone resorption after PTX.