Bone Abstracts

Introduction: Diabetes mellitus may affect bone via bone structure, bone density, and biochemical markers of bone turnover. The aim of this meta-analysis was to examine biochemical markers of bone turnover in diabetics compared to non-diabetics.

Methods: A systematic literature search was conducted using Pubmed, Embase, Cinahl, and Svemed+ with the search terms: ‘Diabetes mellitus’, ‘Diabetes mellitus type 1’, ‘Insulin dependent diabetes mellitus’, ‘Diabetes mellitus type 2’, ‘Non insulin dependent diabetes mellitus’, ‘Bone’, ‘Bone and Bones’, ‘Bone diseases’, ‘Bone turnover’, ‘Hemoglobin A Glycosylated and ‘HbA1c’. After removing duplicates from this search 1188 records were screened by title and abstract and 75 records were assessed by full text for inclusion. After screening, 22 records fulfilled the criteria for the meta-analysis. Revman was used in the data analysis.

Results: From the pooled data in the meta-analysis the bone markers, osteocalcin (P<0.01), and CTX (P<0.01) were significantly lower among diabetics than non-diabetics, however, bone specific alkaline phosphatase (P=0.53), deoxypyridinoline (P=0.99), NTX (P=0.06) and C1CP (P=0.54) did not differ. Alkaline phosphatase (P<0.01) was increased in diabetics. I relation to calcitropic hormones; 25-hydroxy vitamin D was lower in diabetics (P=0.02), while PTH (P=0.56) and serum calcium (P=0.54) remained unchanged. All markers displayed very high heterogeneity by I² statistics. No publication bias was present (analyses by funnel plot).

Conclusion: A dissociative pattern of biochemical bone markers of formation and bone resorption was present in diabetics. We speculate that this could point to a measurement error caused by glycation of bone markers, which may alter the configuration of some of the markers thus disrupting the measurement of these.