title: Subtle changes in bone mineralization density distribution in most severely affected patients with chronic obstructive pulmonary disease.
abstract: Chronic obstructive pulmonary disease (COPD) is associated with low aBMD as measured by DXA and altered microstructure as assessed by bone histomorphometry and microcomputed tomography. Knowledge of bone matrix mineralization is lacking in COPD. Using quantitative backscatter electron imaging (qBEI), we assessed cancellous (Cn.) and cortical (Ct.) bone mineralization density distribution (BMDD) in 19 postmenopausal women (62.1 ± 7.3 years of age) with COPD. Eight had sustained fragility fractures, and 13 had received treatment with inhaled glucocorticoids. The BMDD outcomes from the patients were compared with healthy reference data and were correlated with previous clinical and histomorphometric findings. In general, the BMDD outcomes for the patients were not significantly different from the reference data. Neither the subgroups of with or without fragility fractures or of who did or did not receive inhaled glucocorticoid treatment, showed differences in BMDD. However, subgroup comparison according to severity revealed 10% decreased cancellous mineralization heterogeneity (Cn.CaWidth) for the most severely affected compared with less affected patients (p=0.042) and compared with healthy premenopausal controls (p=0.021). BMDD parameters were highly correlated with histomorphometric cancellous bone volume (BV/TV) and formation indices: mean degree of mineralization (Cn.CaMean) versus BV/TV (r=0.58, p=0.009), and Cn.CaMean and Ct.CaMean versus bone formation rate (BFR/BS) (r=-0.71, p<0.001). In particular, those with lower BV/TV (<50th percentile) had significantly lower Cn.CaMean (p=0.037) and higher Cn.CaLow (p=0.020) compared with those with higher (>50th percentile) BV/TV. The normality in most of the BMDD parameters and bone formation rates as well as the significant correlations between them suggests unaffected mineralization processes in COPD. Our findings also indicate no significant negative effect of treatment with inhaled glucocorticoids on the bone mineralization pattern. However, the observed concomitant occurrence of relatively lower bone volumes with lower bone matrix mineralization will both contribute to the reduced aBMD in some patients with COPD.
authors.affiliation: Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria. Electronic address: barbara.misof@osteologie.at.
authors.forename: B M
authors.initials: BM
authors.lastname: Misof
authors.affiliation: Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Roschger
authors.affiliation: Department of Nephrology, School of Medicine, University of Sao Paulo, SP, Brazil.
authors.forename: V
authors.initials: V
authors.lastname: Jorgetti
authors.affiliation: Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Klaushofer
authors.affiliation: Endocrine Division (SEMPR), Department of Internal Medicine, Clinical Hospital of the Federal University of Parana, Curitiba, PR, Brazil.
authors.forename: V Z C
authors.initials: VZ
authors.lastname: Borba
authors.affiliation: Endocrine Division (SEMPR), Department of Internal Medicine, Clinical Hospital of the Federal University of Parana, Curitiba, PR, Brazil.
authors.forename: C L
authors.initials: CL
authors.lastname: Boguszewski
authors.affiliation: Department of Medicine, Division of Endocrinology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: A
authors.initials: A
authors.lastname: Cohen
authors.affiliation: Department of Medicine, Division of Endocrinology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: E
authors.initials: E
authors.lastname: Shane
authors.affiliation: Regional Bone Center, Helen Hayes Hospital, West Haverstraw, New York, USA.
authors.forename: H
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Pathology, Columbia University College of Physicians and Surgeons, New York, NY, USA; Regional Bone Center, Helen Hayes Hospital, West Haverstraw, New York, USA.
authors.forename: D W
authors.initials: DW
authors.lastname: Dempster
authors.affiliation: Endocrine Division (SEMPR), Department of Internal Medicine, Clinical Hospital of the Federal University of Parana, Curitiba, PR, Brazil.
authors.forename: C A
authors.initials: CA
authors.lastname: Moreira
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000502:physiology*; D001851:Bone Diseases, Metabolic / Q000453:epidemiology; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D002113:Calcification, Physiologic / Q000502:physiology*; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D010024:Osteoporosis / Q000453:epidemiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology; D055114:X-Ray Microtomography
keywords: Bone matrix mineralization; Chronic obstructive pulmonary disease; Quantitative backscatter electron imaging; Transiliac bone biopsy