Changes in Bone Mineral Density with Age in Men and Women: A Longitudinal Study

Abstract

We performed a prospective study to evaluate the normal changes in bone mineral density (BMD) in the forearm, hip, spine and total body, and to study the agreement between changes in BMD estimated from cross-sectional data and the actual longitudinal changes. Six hundred and twenty subjects (398 women, 222 men; age 20-89 years) without diseases or medication known to affect bone metabolism undertook baseline evaluations, and 525 (336 women, 189 men) completed the study. BMD was measured twice 2 years apart by dual-energy X-ray absorptiometry. From cross-sectional evaluations the only premenopausal bone loss (<0.003 g/cm2/year) was found in the hip. In women after menopause and in men an age-related bone loss (0.002-0.006 g/cm2/year) was found at all sites. The data from the longitudinal evaluation showed a small bone loss in women before menopause at the hip and lumbar spine (<0.4%/year (<0.004 g/cm2/year)); this bone loss nearly tripled in the early postmenopausal years (<10 years since menopause), and thereafter decreased to the premenopausal rate for the hip, and to zero for the lumbar spine. The most pronounced bone loss after menopause occurred in the forearm (1.2%/year (0.006 g/ cm2/year)), and it remained constant throughout life. In men there was a small longitudinal bone loss in the hip throughout life, and a small bone loss in the distal forearm after the age of 50 years. In all groups, except for the early postmenopausal women, we found a small increase in total body BMD with age. When comparing the changes in BMD estimated from cross-sectional data with the longitudinal changes, only the hip and forearm generally displayed agreement, whereas the changes in the total body and spine generally were incongruous. In conclusion, the hip and forearm appear to be the sites with the best agreement between the cross-sectional estimated and the longitudinal age-related changes in BMD.

Genetic influences on bone loss in the San Antonio Family Osteoporosis study

“…While the cumulative influence of genes on ΔBMD is large, the contribution of environmental factors is also important; measured covariates accounted for 10% to 28% of phenotypic variation. Associations with BMD of several of the environmental correlates identified in this study, including age, female sex, postmenopausal status, low body weight, and weight loss, have been detected in previous studies [11][12][13]37]. Interestingly, we observed differences in magnitude and direction for ΔBMD across skeletal sites, as has been observed by others, although not always for the same sites [9][10][11].…”

“…Cross-sectional study designs cannot sufficiently distinguish between processes leading to peak BMD acquisition versus loss with age, and this has been a persistent limitation of cross-sectional epidemiological and genetic studies of BMD, particularly those carried out in older individuals since such studies cannot allow for variation in rates of change in BMD during aging. Longitudinal studies have shown that weight, interim change in weight, alcohol consumption, smoking, sex, estrogen replacement therapy, menopausal status, exercise, calcium intake, and serum vitamin D level may affect change in BMD over time, and that rates of BMD change may differ among skeletal sites [9][10][11][12][13]. Rate of bone loss as a risk factor for fracture independent of bone mass has recently been reported in a cohort of postmenopausal women (mean age of 62 years) [14], reinforcing the clinical importance of change in BMD for bone health.…”

Muscle strength is a determinant of bone mineral content in the hemiparetic upper extremity: Implications for stroke rehabilitation

“…Bone mineral levels in the upper extremity normally decline with age [51]. However, we did not find such a correlation in our study.…”

Integration of ‘omics’ data in aging research: from biomarkers to systems biology

“…Dozens of clinical phenotypes, such as Parkinson's (Reeve et al ., 2014), AD (McAuley et al ., 2009), body mass index, blood pressure (Mungreiphy et al ., 2011) and bone mineral density (Warming et al ., 2002), as well as lifestyle parameters, such as nutrition (Wieser et al ., 2011), smoking and physical activity, are strongly related to age (Harman, 1988; Wang et al ., 2009). Composite measures such as the Rockwood frailty index (Rockwood & Mitnitski, 2007) combine several of those clinical traits to form a more homogenous phenotype – frailty – from its diverse appearance.…”

“…In contrast, biological age is a broader concept that takes the individual physical and mental health into account, thus capturing individual differences of the aging process. Most aging studies search for associations of chronological age with clinical and molecular phenotypes (Warming et al ., 2002). However, several studies used phenotypes, such as lung function, grip strength or bone mineral density, as proxies to investigate molecular changes in biological aging (Jackson et al ., 2003; Bell et al ., 2012; Levine, 2013).…”