Impairment of bone turnover in elderly women with hip fracture

Abstract

Hip fracture is one of the most severe consequences of osteoporosis affecting aged women. However, abnormalities of bone turnover responsible for bone loss in this condition have not been clearly defined. To further evaluate the bone metabolic status of women sustaining hip fracture, we have prospectively measured serum osteocalcin as a marker of bone formation and urinary excretion of pyridinoline (Pyr) and deoxypyridinoline (D-pyr) cross-links as markers of bone collagen degradation in 174 independently living women (80 +/- 8 years) within a few hours after a hip fracture. Comparison was made with 77 age-matched controls (80 +/- 5 years) and 17 premenopausal women (39 +/- 3 years). In addition 15 of the patients were followed with daily measurements during the first postoperative week. At the time of admission osteocalcin was 20% lower in the fractured women compared to the elderly controls (7.6 +/- 3.8 vs. 9.5 +/- 4.5 ng/ml, P = 0.001). Pyr and D-pyr were 36% and 40% higher, respectively (P = 0.0001), than in elderly controls and 85% and 76% higher than in premenopausal controls (P = 0.0001). Serum osteocalcin did not correlate with the cortisol level measured at the same time (r = 0.03, ns), nor with serum albumin and creatinine. Serum osteocalcin remained unchanged within 18 hours after fracture, whereafter it progressively decreased until the third postoperative day. No correlation was noted between the excretion of pyridinoline cross-links and the time elapsed from fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical application of biochemical markers of bone turnover

“…It is now widely accepted that the accelerated rate of bone loss seen after the menopause is mainly due to an uncoupling in bone turnover and an increase in bone resorption (26,27). Studies employing specific bone markers indicate that bone turnover continues to be increased (and to be associated with bone loss) during late menopause (28)(29)(30)(31)(32)(33). In some postmenopausal women (34), but particularly in the very elderly (35)(36)(37), this increase in bone turnover is often, but not always, found to be due to vitamin D and/or calcium deficiency and secondary hyperparathyroidism.…”

“…In retrospective population-based studies, Akesson and co-workers (28,29,43,44) have demonstrated that previous fractures were associated with abnormal bone turnover. After adjustment for age and BMD, women with fractures occurring within six years prior to the study were characterised by lower serum levels of OC and PICP, but normal rates of bone resorption.…”

Biochemical markers of bone turnover:A review

“…On the other hand, using more sensitive biochemical markers, the osteocalcin level was 20 percent lower in women with hip fracture, whereas the bone resorption, as measured by the pyridinoline excretion, was 40 percent higher. Thus, elderly women with hip fracture presented biochemical evidence of an imbalance of bone turnover with decreased formation and increased resorption, a bone metabolic deficiency which may play a role in the development of a low bone mass (134). However, the ability to increase the bone turnover in response to the fracture-healing process was intact; osteocalcin and ALP were increased at 3-7.5 months after the fracture (133).…”

Serum Concentrations of Cross-Linked N-Telopeptides of Type I Collagen: New Marker for Bone Resorption in Hemodialysis Patients

“…Bone mineral density (BMD) is widely used to estimate bone fracture risk. In addition, evaluation of bone turnover rate is established as an independent predictor for bone fracture (2,3 ) and future bone loss (4 ), and measurements of bone metabolic markers are increasingly used to complement BMD measurements (5,6 ). Bone resorption markers are assumed to be superior to bone formation markers for predicting future changes in bone mass, well in advance of detection of BMD reductions (7 ).…”