Metacarpal bone mineral density, body mass index and lifestyle among postmenopausal Japanese women: relationship of body mass index, physical activity, calcium intake, alcohol and smoking to bone mineral density: the Hizen-Oshima study.
ABSTRACT The present study was designed to investigate the influence of modifiable risk factors (body weight and lifestyle) for bone loss on bone mineral density (BMD). We examined age-specific changes in metacarpal BMD, and its associations with body mass index and lifestyle among 532 community-dwelling postmenopausal Japanese women. Measurements of the second metacarpal BMD were obtained from the hand radiographs using computer-assisted radiographic absorptiometry. Body height and weight were measured, and body mass index (BMI) was calculated. Physical activity index was calculated using validated questionnaire. Daily calcium intake and amount of ingested alcohol were estimated by semiquantitative food frequency questionnaire. Current smoking status was obtained by questionnaire. Metacarpal BMD decreased significantly with increasing age. Simple correlation analysis indicated that metacarpal BMD correlated significantly with BMI and physical activity index. On the other hand, metacarpal BMD did not correlate with calcium intake and alcohol drinking. Metacarpal BMD in current smokers was not different from that in nonsmokers. Multiple regression analysis showed that increasing age was associated with decreased metacarpal BMD and greater BMI increased metacarpal BMD. However, physical activity, calcium intake, alcohol drinking and current smoking were not significant determinants of metacarpal BMD. Our findings suggest that maintenance of adequate body mass (prevention for leanness) is important for prevention of postmenopausal bone loss.
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ABSTRACT: The aim of this study was to examine the association of exercise frequency and calcium intake (CI) with change in regional and total bone mineral density (BMD) in a group of postmenopausal women completing 4 years of progressive strength training. One hundred sixty-seven calcium-supplemented (800 mg/day) sedentary women (56.1+/-4.5 years) randomized to a progressive strength training exercise program or to control were followed for 4 years. Fifty-four percent of the women were using hormone therapy (HT) at baseline. At 1 year, controls were permitted to begin the exercise program (crossovers). The final sample included 23 controls, 55 crossovers, and 89 randomized exercisers. Exercisers were instructed to complete two sets of six to eight repetitions of exercises at 70-80% of one repetition maximum, three times weekly. BMD was measured at baseline and thereafter annually using dual-energy X-ray absorptiometry. Four-year percentage exercise frequency (ExFreq) averaged 26.8%+/-20.1% for crossovers (including the first year at 0%), and 50.4%+/-26.7% for exercisers. Four-year total CI averaged 1,635+/-367 mg/day and supplemental calcium intake, 711+/-174 mg/day. In adjusted multiple linear regression models, ExFreq was positively and significantly related to changes in femur trochanter (FT) and neck (FN), lumbar spine (LS), and total body (TB) BMD. Among HT users, FT BMD increased 1.5%, and FN and LS BMD, 1.2% (p<0.01) for each standard deviation (SD) of percentage ExFreq (29.5% or 0.9 days/week). HT non-users gained 1.9% and 2.3% BMD at FT and FN, respectively, (p<0.05) for every SD of CI. The significant, positive, association between BMD change and ExFreq supports the long-term usefulness of strength training exercise for the prevention of osteoporosis in postmenopausal women, especially HT users. The positive relationship of CI to change in BMD among postmenopausal women not using HT has clinical implications in light of recent evidence of an increased health risk associated with HT.Osteoporosis International 01/2006; 16(12):2129-41. · 4.58 Impact Factor