Fragility Fracture Incidence in Chronic Obstructive Pulmonary Disease (COPD) Patients Associates With Nanoporosity, Mineral/Matrix Ratio, and Pyridinoline Content at Actively Bone-Forming Trabecular Surfaces

Abstract

Chronic obstructive pulmonary disease (COPD) is associated with low areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) and altered microstructure by bone histomorphometry and micro-computed tomography. Nevertheless, not all COPD patients sustain fragility fractures. In the present study, we used Raman microspectroscopic analysis to determine bone compositional properties at actively forming trabecular surfaces (based on double fluorescent labels) in iliac crest biopsies from 19 postmenopausal COPD patients (aged 62.1 ± 7.3 years). Additionally, we analyzed trabecular geometrical centers, representing tissue much older than the forming surfaces. Eight of the patients had sustained fragility fractures, and 13 had received treatment with inhaled glucocorticoids. None of the patients had taken oral glucocorticoids. The monitored parameters were mineral/matrix ratio (MM), nanoporosity, and relative glycosaminoglycan (GAG), lipid, and pyridinoline contents (PYD). There were no significant differences between the glucocorticoid-treated patients and those who did not receive any. On the other hand, COPD patients sustaining fragility fractures had significantly lower nanoporosity and higher MM and PYD values compared with COPD patients without fragility fractures. To the best of our knowledge, this is the first study to discriminate between fracture and non-fracture COPD patients based on differences in the material properties of bone matrix. Given that these bone material compositional differences are evident close to the cement line (a major bone interface), they may contribute to the inferior bone toughness and coupled with the lower lumbar spine bone mineral density values result in the fragility fractures prevalent in these patients. © 2016 American Society for Bone and Mineral Research.

Fructus Ligustri Lucidi preserves bone quality through the regulation of gut microbiota diversity, oxidative stress, TMAO and Sirt6 levels in aging mice

“…Thus, we inferred that FLL might delay the bone matrix aging process. In addition, deterioration of bone material composition and microstructure leads to the decreased bone strength [55]. Intriguingly, we illustrated that FLL treatment improved ultimate load, bending strength, and elastic modulus.…”

Bone quality changes associated with aging and disease: a review

“…In addition to lupus and rheumatoid arthritis, asthma, and other conditions in which glucocorticoids are used for extended periods, fracture risk is increased in individuals with COPD taking inhaled steroids. While life‐style features leading to COPD also affect bone turnover and fracture risk, there is a single study comparing bone quality in newly formed and older bone of individuals with COPD who did and did not sustain fragility fractures on the basis of Raman spectroscopy. Interestingly, no differences were noted between the glucocorticoid‐treated individuals with COPD and those who were not treated with glucocorticoids.…”

“…[5][6][7] Bone turnover is generally measured by histomorphometry, 8 although it can be approximated from urinary turnover-markers. 9 Macroscopic cortical porosity has been measured by microcomputed tomography (microCT) 10 MRI; 11 however, newer methods exist on the basis of Raman spectroscopy 12,13 and short-wave infrared Raman spectroscopy 14 that have also been applied to measure water content. Damage has been assessed by basic Fuschin staining 15 and more recently by synchrotron radiation transmission X-ray microscopy with an X-ray negative stain.…”

Differences in bone density on chest CT according to smoking status in males without chronic obstructive lung disease

“…In many previous studies, CTBD has been shown to be an effective method of demonstrating bone mineral loss and has shown good correlation with DEXA-BMD 1,5,7,9,11–16 . Recently, it was also reported that CTBD reflects bone mineral loss more sensitively than DEXA, although CTBD measures were calibrated using specific formulas 12 .…”