Cross-sectional assessment of age-related bone loss in men: The MINOS study

There are few data on osteoporosis in men, but cross-sectional studies have shown that age-related bone loss in men is of loner magnitude than in wome n. To elucidate some controversies related partially to methodological aspe cts, we measured bone mineral density (BMD) by dual energy X-ray absorptiom etry (DEXA) at various skeletal sites (spine, hip, and whole body using a H ologic QDR-1500 device; forearm using an Osteometer DTX 100 device) in a la rge cohort of 1040 men, aged 19-85 years. The final investigation was perfo rmed on 934 men, aged 19-85 years, after exclusion of 106 men with disease or treatment known to affect bone metabolism. Peak BMD was achieved at 25 a nd 29 years at the lumbar spine and hip, respectively, but only at 40 and 3 7 Sears at the distal forearm and whole body, respectively, The magnitude o f bone loss between peak bone mass and 80 years of age was linear at most s ites and averaged 13%-18%; that is, SD of 1.1-1.8 from peak BMD, except for Ward's triangle, which showed a marked bone loss of 43% (i.e., 2.5 SD), an d for the lumbar spine. In the entire cohort, increase of the average lumba r spine BMD after the age of 55 years was related to the development of ost eoarthritis, because, in men without severe arthritis, lumbar spine BMD con tinued to decrease. Height-adjusted partial correlations indicate that both the mineral content and the area of long bones of tbe limbs increased with age up to 50 years, followed by a significant decrease of BMD without chan ge of bone surface. SD of mean BMD increased significantly with age at most skeletal sites. Tn summary, age-related change of BR ID varied according t o skeletal site in men with peak bone mass achieved earlier at sites rich i n trabecular bone than at those rich in cortical bone. Bone loss varied acc ording to skeletal site from 14% to 43%, The variability of BMD increased w ith age, which mag reflect interindividual variability of age-related bone loss. (C) 2000 by Elsevier Science Inc, All rights reserved.