Relationship of Body Fat and Its Distribution With Bone Mineral Density in Indian Population

Obesity has been associated with increased bone mineral density (BMD). There is evidence of differential effect of regional fat on BMD. Hence, we undertook this study to evaluate the correlation between total body fat and its distribution with BMD in nonobese (mean body mass index: 25.0 ± 4.7 kg/m²) Indian adult volunteers. A total of 2347 participants (men: 39.4% and women: 60.6%) included in this cross-sectional study were divided according to sex and age. Fasting blood samples were drawn for biochemical parameters. Percent total body, truncal, and leg fat and BMD at lumbar spine, femur, and forearm were measured by dual-energy X-ray absorptiometry. The BMD at all sites (radius, femur, and spine) increased from lowest to highest quartiles of percent body fat. Percent truncal fat was positively correlated with BMD at all sites in both sexes, except for femoral neck in men, where it had negative correlation. Percent leg fat was positively related with BMD at all sites in premenopausal women, and spine and radius BMD in postmenopausal women. However, in men, it had negative correlation with femoral neck BMD. On multiple regression analysis, regional fat had positive association with BMD at all sites after adjusting for age, sex, lean mass index, 25-hydroxyvitamin D, and intact parathyroid hormone levels. Leg-to-total body fat ratio was negatively associated with BMD at all sites in men and pre- and postmenopausal women. Percent total body and regional fat have positive association with BMD at all sites in men and women.     

Body composition and bone density in Canadian White and Aboriginal women: the First Nations Bone Health Study

Ethnic variation in soft tissue composition may contribute to observed ethnic differences in bone mineral density (BMD). This analysis was performed to determine whether ethnic differences in body composition affect differences in BMD between Canadian White and Aboriginal women. An age-stratified population-based sample of 206 Aboriginal women and 177 White women underwent multisite bone density measurements and total body soft tissue composition analysis. In univariate analyses, each kg of additional lean mass was associated with a greater increase in BMD than an equal amount of fat mass (p < .01). When models simultaneously evaluated both soft tissue measurements, lean mass (but not fat mass) was positively correlated with BMD at all measurement sites (p < .001). Aboriginal women had significantly lower weight-adjusted BMD than White women for two sites (calcaneus, p = .019; total body, p = .026) and lower BMI-adjusted for BMD three sites (calcaneus, p = .0076; distal forearm, p = .047; total body, p = .022). The ratio of lean mass to fat mass was lower in Aboriginal than White women (p < .001). When BMD was adjusted for body composition variables no significant difference was seen between Aboriginal and White women. Apparent ethnic differences in weight- and BMI-adjusted BMD between Canadian White and Aboriginal women were explained by a lower ratio of lean mass to fat mass in Aboriginal women, combined with a smaller increment in BMD from fat mass versus lean mass in both populations.     

Bone mineral density measured by dual-energy X-ray absorptiometry in healthy finnish women

Summary A cross-sectional study of 351 healthy Finnish women aged 20–76 years was done to establish reference values of bone mineral density (BMD) using dual-energy X-ray absorptiometry (DEXA). The effects of age and of several physical and lifestyle factors on BMD of the lumbar spine and proximal femur (femoral neck, trochanter, and Ward's triangle area) were investigated. Altogether 58 women were excluded from the final analysis due to significant spinal osteoarthritis or other diseases or drugs known to influence calcium or bone metabolism. The precision of the method was 0.9, 1.2, 2.7, and 2.4% in the lumbar, femoral neck, Ward's triangle and trochanter area, respectively. Lumbar BMD was increased by 30% (P<0.001) in 15 patients with osteoarthritis (21% of women 50 years or older), but it was apparently unaffected in 5 cases with aortic calcification. Except for the trochanter area, BMD diminished along with age, and this was significant after the menopause. The peak of mean BMD was observed at the age of 31–35 years in the spine and at the age of 20–25 years in the femoral neck and Ward's triangle. BMD was in a positive relationship to weight both in premenopausal and postmenopausal women and to the use of oral contraceptives in premenopausal women and to that of estrogen replacement therapy in postmenopausal women. Labors and pregnancies had a weak positive effect on BMD in premenopausal women. As compared with nonusers premenopausal women who had used alcohol showed a slightly decreased BMD of Ward's triangle. In postmenopausal women there was a positive correlation between alcohol intake and BMD.     

Bone mineral density and body composition in adult patients with cystic fibrosis.

BACKGROUND--Cystic fibrosis is a multisystem disease characterised by chronic pulmonary sepsis and malnutrition. To ascertain whether osteoporosis is a feature of cystic fibrosis in adult patients, total body and regional bone mineral density (BMD) was measured in a group of eight men and eight women aged 17-42 years. METHODS--Total body and regional BMD (lumbar spine L2-L4, femoral neck, trochanteric, and Ward's triangle), as well as total body fat and lean mass, were measured by dual energy x ray absorptiometry. A range of biochemical, lifestyle, and anthropometric variables was also assessed. RESULTS--Patients with cystic fibrosis had significantly reduced bone density at all sites compared with normal young adults. The mean reductions ranged from 7% at Ward's triangle to 13% at the trochanter. Body mass index (BMI) was positively correlated with BMD at four sites and disease severity negatively correlated with BMD at two sites. Other biochemical and anthropometric variables were not predictive of bone density. Total body fat mass was reduced by 30% compared with normal young adults. CONCLUSIONS--Bone density is decreased in adult patients with cystic fibrosis and BMI and disease severity are independent predictors of bone density.     

Effects of isoflavone and exercise on BMD and fat mass in postmenopausal Japanese women: a 1-year randomized placebo-controlled trial.

The combined intervention of isoflavone intake and walking exercise over 1 year in postmenopausal Japanese women exhibited a trend for a greater effect on prevention of bone loss at the total hip and Ward's triangle regions. INTRODUCTION: The additive effects of isoflavones and exercise on bone and lipid metabolism have been shown in estrogen-deficient animals. In this study, we determined the effects of isoflavone intake, walking exercise, and their interaction on bone, fat mass, and lipid metabolism over 1 year in postmenopausal Japanese women. MATERIALS AND METHODS: A total of 136 postmenopausal women at <5 years after the onset of menopause were randomly assigned to four groups: (1) placebo, (2) walking (45 minutes/day, 3 days/week) with placebo, (3) isoflavone intake (75 mg of isoflavone conjugates/day), and (4) combination of isoflavone plus walking. BMD, fat mass, serum lipid, and serum and urinary isoflavone concentrations were assessed. RESULTS: A significant main effect of isoflavone on the reduction in trunk fat mass was obtained at 12 months. Significant main effects of walking on the reduction in fat mass in the whole body and the trunk were observed at 3, 6, and 12 months and that in the legs and arms at 6 and 12 months. Serum high-density lipoprotein (HDL)-cholesterol concentration significantly increased by 12 months after the walking and the combined intervention. After 12 months, a significant main effect of isoflavone on BMD was observed only at Ward's triangle. Walking prevented bone loss at the total hip and the Ward's triangle to significant degrees. The effect of the combined intervention on BMD at total hip and Ward's triangle regions was greater than that of either alone. No significant interaction was observed between isoflavone and walking in any measurements recorded during the study. CONCLUSIONS: Our study suggest that combined intervention of 75 mg/day of isoflavone intake and walking exercise 3 times/week for 1 year showed a trend for a greater effect on BMD at total hip and Ward's triangle regions than either alone. Intervention with isoflavone in postmenopausal Japanese women showed a modest effect on BMD compared with those in Westerners. Further studies over longer treatment duration that include assessment of BMD at various regions are necessary to ascertain the clinical significance of the combined intervention of isoflavone plus walking in postmenopausal women.     

探讨体重指数对绝经后老年妇女不同部位骨密度的影响

目的分析不同体重指数患者的腰椎和股骨近端、股骨颈、Ward’s三角区的骨密度及T值评分,探讨体重指数对绝经老年妇女不同部位骨密度的影响。方法以我院225例年龄均为60以上的绝经老年妇女为研究对象,计算体重指数将患者分为体瘦组、正常组和肥胖组,检测患者腰椎和股骨近端、股骨颈、Ward’s三角区的骨密度,分析各部位骨密度变化与体重指数的关系。结果体瘦组的患者各部位骨密度明显低于正常和肥胖组的患者,体瘦组与正常组或肥胖组比较,腰椎(L1～L4)、股骨颈、股骨近端、Ward’s三角区的骨密度均有显著的差异(P<0.01);正常组与肥胖组比较,仅L3和L4的骨密度有显著的差异(P<0.05),其余部位的骨密度无显著的差异(P>0.05)。结论体重和体重指数是影响骨密度的一个重要因素,体重和体重指数与绝经老年妇女不同部位的骨密度存在一定的相关性,低体重指数的绝经老年妇女,骨丢失而引起的骨量减少明显,易发生骨质疏松。     

Serum uric acid plays a protective role for bone loss in peri- and postmenopausal women: A longitudinal study

ObjectiveOxidative stress has been linked to osteoporosis. Serum uric acid (UA), a strong endogenous antioxidant, has been associated with higher bone mineral density (BMD), lower bone turnover and lower prevalence of fractures in a large cross-sectional study of men. Whether this relationship is present in women and how UA relates to changes in BMD longitudinally has not been examined.MethodsA sample of 356 peri- and postmenopausal women, mean age 60.5 years was studied. Each individual had baseline BMD and body composition measurements by dual energy x-ray absorptiometry (DXA) and at least one repeat measure, on average 9.7 years later. Annual rate of change in BMD (A%ΔBMD) was calculated. UA was measured at each DXA visit. Calciotropic hormones and bone turnover markers were measured at the final visit only.ResultsCross-sectional data analyses revealed that women with higher UA levels had significantly higher absolute BMD measures at all skeletal sites. These women also had higher measures of body weight and its components such as lean mass (LM) and fat mass (FM). Results of multiple regression analyses showed a positive association between UA and BMD that remained significant even after accounting for possible confounders including LM and FM. Regression analyses of the longitudinal BMD data demonstrated significant associations between serum UA levels and annual rates of change in BMD at all skeletal sites. After adjustment associations remained significant for lumbar spine, forearm and whole body BMD but not for hip BMD.ConclusionHigher serum UA levels appear to be protective for bone loss in peri- and postmenopausal women and this relationship is not affected by changes in body composition measures.     

Bone mass and body composition in normal women.

The interrelationships between measurements of bone mass and total-body bone mineral were examined in a cross-sectional study of normal healthy women aged 17-82 years. In addition we evaluated the relationship between measures of body composition, estimated by four independent techniques, and bone mass in the same population. Considering the group as a whole, bone mass at all sites correlated with each other and with total-body bone mineral (TBBM). Cancellous and cortical sites could predict TBBM equally well. As expected, all measurements of bone mass were significantly lower in postmenopausal women in comparison to premenopausal women. Declines in bone mass were only seen in premenopausal women in the femoral neck and Ward's triangle, not in lumbar spine, radius, or skeleton as a whole. In postmenopausal women bone mass correlated negatively with age and years from menopause equally at all sites. TBBM was significantly related to height and weight in both premenopausal and postmenopausal women. In premenopausal and postmenopausal women TBBM also correlated with fat mass, but TBBM was much better correlated with percentage body fat in premenopausal than postmenopausal women. TBBM was a constant proportion of lean body mass in premenopausal women, but the fraction of lean mass occupied by the skeleton declined with age in postmenopausal women. Correction of TBBM for lean mass did not change the relationship between TBBM and percentage fat in premenopausal women but eliminated the relationship in postmenopausal women. Regional measurements, which are at least partially corrected for body size by dividing mass by area, correlated less well with height and weight and with any index of obesity, especially in postmenopausal women.     

Correlation of Bone Density to Strength and Physical Activity in Young Men with a Low or Moderate Level of Physical Activity

The objective of this study was to evaluate the relationship among bone mineral density (BMD), physical activity, muscle strength, and body constitution, in young men with a low or moderate level of physical exercise. Another aim was to investigate whether the head is unaffected by physical activity. The subjects consisted of 33 Caucasian healthy men, mean age 24.8 ± 2.3 years. BMDs of the total body, lumbar spine (L2-L4), femoral neck, Ward's triangle and trochanter, humerus, and head were measured using dual-energy-X-ray absorptiometry (DXA). Bivariate correlations were measured among the different BMD sites and age, weight, height, body mass index (BMI), fat mass, lean body mass, amount of physical activity (hours/week), hamstrings strength, and quadriceps strength. Significant predictors were found for all BMD sites except the head. Using all these variables, only 6% of the variation in BMD of the head could be explained, whereas 46% (total body), 31% (humerus), 17% (lumbar spine), 38% (femoral neck, Ward's), and 41% could be explained for the trochanter. Physical activity and muscle strength were found to be independent significant predictors of BMD of the total body and the sites at the proximal femur. These results suggest that at the time of peak bone mass attainment, physical activity is an important predictor of the clinically relevant proximal femur in young men with a low or moderate level of physical activity. Furthermore, since head BMD was not related to the level of physical activity, we suggest that head BMD may be used as an internal standard, to control for selection bias, in studies investigating the effect of physical activity on bone mass. Received: 5 February 1996 / Accepted: 24 September 1996     

Contribution of Android and Gynoid Adiposity to Bone Mineral Density in Healthy Postmenopausal Thai Women

Dual-energy X-ray absorptiometry (DXA) is one of the major tools for assessing the whole body and regional body composition and body adiposity. Various body composition parameters including android fat mass (AFM), gynoid fat mass (GFM), and android-to-gynoid fat ratio (AG fat ratio) obtained from whole body DXA can be used as a reliable surrogate marker for regional body composition analysis. This study aimed to explore the contribution of android and gynoid adiposity to bone mineral density (BMD) in healthy postmenopausal Thai women. This cross-sectional study enrolled 1448 healthy Thai women, ages 40–90 without medication history or known disease affecting the BMD. Lumbar spine (LS), total femur, and femoral neck BMDs, AFM, GFM, and AG fat ratio were measured by DXA. To evaluate the contribution of android and gynoid adiposity with various measures of BMDs, univariable and multivariable linear regression analyses were used to estimate the regression coefficients. AFM, GFM, and AG fat ratio had a significant positive association with BMD of all measured sites (p < 0.001) in the univariate analysis. The strongest association was found between AG fat ratio and LS BMD (β = 0.156, p ≤ 0.001). In multivariate linear regression analysis, the results continued to show a positive association between AFM and GFM at all skeletal sites after adjusting for age, height, and total body lean mass. Relationship between AG fat ratio and BMD was found only in LS region. GFM had a strongest positive effect with BMD at the LS, total femur, and femoral neck regions. Higher android and gynoid adiposity was associated with higher BMD. GFM rather than AFM shows the strongest positive association with BMDs in postmenopausal Thai women.     

Negative Association between Metabolic Syndrome and Bone Mineral Density in Koreans, Especially in Men

Cardiovascular disease and osteoporosis are thought to share common risk factors, and metabolic syndrome (MS) is composed of major risk factors for cardiovascular disease. This study was performed to investigate the relationships between specific MS components and bone mineral density (BMD). BMD was measured at the femoral neck of Korean men aged 40 years or more (n = 1,780) and postmenopausal women (n = 1,108) using dual-energy X-ray absorptiometry. We identified subjects with MS as defined by two criteria, International Diabetes Federation (IDF) and American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI). Body fat and lean mass were measured via bioimpedance analysis. The prevalence of MS was 19.8% and 7.7% in men and 20.8% and 11.6% in postmenopausal women according to the AHA/NHLBI definition and the IDF definition, respectively. After multivariate adjustment, femoral neck BMD was significantly lower in subjects with MS regardless of diagnostic criteria. BMD decreased as the number of MS components increased (P < 0.001 for trends in both sexes). Among MS components, waist circumference was the most important factor in this negative association. When multiple linear regression models were applied to each 5-kg weight stratum to test for a linear trend, waist circumference and fat mass were negatively associated with BMD and lean mass was positively associated with BMD in men but not in women. MS was associated with a lower BMD in Korean men and postmenopausal women, suggesting that visceral fat may lead to bone loss, especially in men.     

Role of serum leptin, insulin, and estrogen levels as potential mediators of the relationship between fat mass and bone mineral density in men versus women

Although fat mass is related to bone mineral density (BMD), the potential mechanism(s) of this effect remain to be defined. Thus, we assessed the role of the candidate hormones, leptin, insulin, and estrogen in mediating fat mass effects on the skeleton. Specifically, we related these hormones and fat mass to BMD at the total hip, mid-lateral spine, and mid-distal radius in a sample of 137 premenopausal women (age range 21-54 years), 165 postmenopausal women (34-93 years), and 343 men (23-90 years) recruited from the general population. Fat mass and BMD were significantly related in pre- and postmenopausal women at multiple sites, whereas this relationship was only weakly present in men at the total hip. Serum leptin levels were also significantly related to BMD in the women, but not in the men. Insulin was associated with hip BMD in the women, and bioavailable estradiol (E2) was correlated with BMD at all sites in men and in postmenopausal women. In the women, adjusting for leptin reduced the strength of the association between fat mass and BMD, with further adjustments for insulin or bioavailable E2 having no additional effects. Adjusting for leptin in the men had no consistent effect on the relationship between fat mass and BMD. Collectively, these data suggest that there is a sexual dimorphism in the relationship of fat mass and leptin to BMD, with both being positively associated with BMD in women but not in men. In women, leptin may also mediate at least part of the protective effect of fat mass on the skeleton.     

Analysis of factors affecting increase in bone mineral density at lumbar spine by bisphosphonate treatment in postmenopausal osteoporosis

Bisphosphonate is an effective drug to reduce fracture risk in osteoporotic patients; however, factors affecting the efficacy of bisphosphonate treatment are not fully known, especially in Japanese patients. In the present study, we examined the relationships between an increase in lumbar spine bone mineral density (BMD) by bisphosphonates and several pretreatment parameters, including biochemical, bone/mineral, and body composition indices, in 85 postmenopausal osteoporotic patients treated with alendronate or risedronate. BMD increase was measured by dual-energy X-ray absorptiometry at the lumbar spine before and 2 years after treatment. BMD increase at the lumbar spine was observed as independent of age, height, weight, body mass index, and fat mass, although lean body mass seemed slightly related. On the other hand, fasting plasma glucose (FPG) levels were significantly and positively related to BMD increase at the lumbar spine. In multiple regression analysis, FPG levels were not significantly related to BMD increase at the lumbar spine when lean body mass was considered. As for bone/mineral parameters, BMD increase at the lumbar spine was not significantly related to serum levels of calcium, parathyroid hormone (PTH), and alkaline phosphatase or urinary levels of deoxypiridinoline and calcium excretion. As for BMD parameters, Z-scores of BMD at any site and bone geometry parameters obtained by forearm peripheral quantitative computed tomography were not significantly related to BMD increase at the lumbar spine. BMD increases at the lumbar spine were similar between groups with or without vertebral fractures. In conclusion, BMD increase at the lumbar spine by bisphosphonate treatment was not related to any pretreatment parameters, including body size, body composition, and bone/mineral metabolism in postmenopausal Japanese women with primary osteoporosis, although FPG correlated partly to BMD through lean body mass.     

High bone-mass density as a marker for breast cancer in post-menopausal women

Bone mass has been proposed as a marker of cumulative exposure to oestrogen in women. We have studied the association between bone mass and breast cancer in postmenopausal women. In 126 cases of breast cancers and 126 controls, the bone mineral density (BMD) of the lumbar spine (L2-L4), femoral neck, trochanter and Ward's triangle was measured by dual-energy X-ray absorptiometry. All cases of cancer were confirmed by pathological reports. A questionnaire including information on reproductive history and other variables was collected. BMD was significantly higher among breast cancer patients than controls at all sites, except at the femoral neck where BMD was increased in the cancer group, but not significantly. After adjustment for potential confounding factors, the estimated relative risk of breast cancer in the highest quartile of BMD compared to the lowest quartile ranged from 2.5 to 4.8 for various sites of measurement. These results confirm that bone-mass density is a strong predictor for breast cancer in postmenopausal women. Women in the lowest quartile of bone mass appear to be protected against breast cancer. The mechanisms underlying this relation may be explained by cumulative exposure to oestrogen.     

The Associations of Body Composition and Fat Distribution With Bone Mineral Density in Elderly Italian Men and Women

This study aimed to investigate the associations of body composition and fat distribution with bone mineral density (BMD) in elderly Italian subjects. In 866 women (age 64.2 ± 6.5 yr) and 168 men (age 65.1 ± 6.1 yr), we measured BMD at lumbar spine, at femur, at the total body, and at the right hand. In all subjects, we also measured sex hormones, 25-hydroxyvitamin D, bone markers, and calcium intake. In both men and women, all body composition parameters had significant positive correlations with BMD at all sites after adjusting for age only; after adjusting also for body weight only lean mass (LM) remained positively associated with BMD at all sites except BMD at lumbar spine. In males, LM was associated with BMD at all sites, whereas android fat was associated with BMD at lumbar spine, at femur, and at whole body. In females, fat mass (FM) was positively and age inversely associated with BMD at all sites, whereas gynoid fat and alkaline phosphatase were inversely associated with BMD at lumbar spine and at femur. In conclusion, the role of LM seems more important in males, whereas in women the role of FM prevails with negative associations between gynoid fat and BMD.     

Gender-Specific Associations of Appendicular Muscle Mass with BMD in Elderly Italian Subjects

Currently used diagnostic measures for sarcopenia are based on the evaluation of appendicular skeletal muscle mass (ASMM) divided by height-squared (ASMMI). This study aimed to investigate the associations between different operational definitions of appendicular muscle mass and BMD at different skeletal sites in aging Italian men and women. In 1199 consecutive healthy Italian subjects, aged 55 years or more (854 women, age 64.2 ± 6.4 years and 165 men, age 65.3 ± 6.1 years), we measured BMD at the lumbar spine (LS-BMD), at femoral neck (FN-BMD),at total hip (TH-BMD), at total body (WB-BMD) and at the right hand (H-BMD) and body composition parameters [ASMM, ASMMI, ASMM/Weight, total lean mass and total fat mass by DXA]. In all subjects, we also measured sex hormones, 25-hydroxyvitamin D and bone turnover markers. In men, both ASMM and ASMMI were positively correlated with BMD at all sites, whereas in women, ASMM and ASMMI did not show any significant correlation with BMD. In men, multiple regression analyses showed that ASMM was positively associated (p < 0.01) with FN-BMD, TH-BMD and H-BMD; however, these associations were no longer present when lean mass was included. In women, both fat mass and lean mass were found positively associated with BMD at all sites. In conclusion, among the different operational measures of the ASMM, only ASMM was significantly associated with BMD in elderly men, but not in elderly women.     

Menopause-related changes in bone mineral density in Japanese women: A longitudinal study on lumbar spine and proximal femur

We investigated 2-year longitudinal changes of bone mineral density (BMD) in lumbar spine and proximal femur in 64 Japanese women aged 38–67. Forty subjects were premenopausal (mean age 44.9) and 24 postmenopausal (mean age 54.6) at enrollment of the study. Six subjects experienced menopause during the 2-year study period and were defined as the perimenopausal group. Measurements of BMD were performed using dual-energy X-ray absorptiometry at L2–4, femoral neck, greater trochanter, and Ward's triangle. Paired t test revealed no significant decrease in BMD at any site in the premenopausal group. Significant annual decrease in BMD was observed in the perimenopausal group at L2–4, femoral neck, and greater trochanter. A similar tendency was observed in Ward's triangle, but did not reach statistical significance. In the postmenopausal group, significant decrease in BMD was found at the proximal femur, but not at L2–4. Significant inverse correlation between age and change rate of BMD was found at L2–4, but not at the proximal femur, in premenopausal women. In postmenopausal women, there was a significant association between body weight (BW) change and change rate in BMD at L2–4, femoral neck, or greater trochanter. This association was not found in the premenopausal group. These results suggest that effect of menopause on BMD may be different in individuals and sites of the skeleton. BW change may affect change in BMD in postmenopausal women. However, the limited variability in both BW and BMD changes among premenopausal women in this study may explain the poor association between change in BW and change in BMD in the premenopausal group. As individual differences in each group is considerably large, annual measurements of BMD may be necessary to find possible candidates for early intervention.     

Bone mass of overweight affluent Indian youth and its sex-specific association with body composition

Summary

The study assessed whether overweight is associated with better bone densities in healthy youth. It was observed that overweight individuals had better BMDs at the hip but not at other sites after controlling for the bone area. Lean body mass was an important determinant of BMDs in men, but both lean and fat mass were important for BMDs in women.

Introduction

The study assessed the relationship of overweight and obesity to the bone mass in young men and women consuming adequate calcium.

Methods

Bone and body composition parameters were measured using dual energy X-ray absorptiometry in overweight men (n?=?74) and women (n?=?77) in the age group of 20–35 years and compared with controls having normal body mass index (BMI). Biochemical parameters of bone metabolism were also assessed.

Results

After adjustment for whole body bone area, bone mineral densities (BMDs) at femoral neck and hip were significantly higher in overweight individuals when compared with controls. However, BMD at lumbar spine, forearm, and whole body were not significantly different in the two BMI groups. Overweight women had lower vitamin D and higher parathormone levels than controls. Regression analyses indicated that height was an important determinant of BMD at most of the skeletal sites in both men and women. Lean body mass was an important determinant of BMDs in men, but both lean and fat mass were important for BMDs in women.

Conclusion

Overweight may be associated with better BMDs at the hip but not at other sites after controlling for the bone area. Body composition parameters may have sex-specific associations with BMD.     

Bone mass after long-term euthyroidism in former hyperthyroid women treated with (131)I influence of menopausal status.

The objective of this study was to assess bone mineral density (BMD) and bone markers in former hyperthyroid females after long-term euthyroidism (>4 yr) following (131)I therapy, as well as the potential influence of the timing of menopause. Twenty-six females ages 57 +/- 8 yr previously diagnosed with hyperthyroidism and treated with (131)I who were euthyroid for a minimum of the last 4 yr (10 +/- 5 yr) were studied. Eighteen patients (69%) were on levothyroxine (LT(4)) replacement therapy for 9 +/- 4 yr. BMD (g/cm(2) and Z-score) was measured by dual X-ray absorptiometry in the lumbar spine, femoral neck, and Ward's triangle. BMD (Z-score) was lower than the normal reference values for the Spanish population in all sites (lumbar spine: -0.65 +/- 1.13; femoral neck: -0.47 +/- 0.95; Ward's triangle: -0.37 +/- 0.88). No differences were found between BMD values according to the etiology of the hyperthyroidism or current LT(4) therapy. Current postmenopausal patients (n = 21) showed lower BMD than current premenopausal patients in the lumbar spine and femoral neck (p < 0.05). Those women who were postmenopausal at the time of the (131)I therapy (n = 15) also had lower lumbar spine BMD than premenopausal patients (p = 0.01), while no significant difference in BMD was seen according to the menopausal status when hyperthyroidism was diagnosed. Former hyperthyroid patients after long-term euthyroidism following (131)I therapy showed reduced BMD at the lumbar spine and proximal femur. Menopausal women showed a greater reduction in bone density. The menopausal status at the time of diagnosis did not seem to have long-term effects in bone density; nevertheless, an early therapeutic intervention in premenopause is suggested to reduce bone loss.     

Spine and femur BMD by DXA in patients with varying severity spinal osteoporosis

Summary Bone mineral density (BMD) at the lumbar spine, femoral neck, trochanteric region, and Ward's triangle was measured using dual-energy X-ray absorptiometry (DXA) in 118 women with osteoporotic vertebral collapse (average age 65 years), divided into four groups according to numbers and SD of vertebral deformation below norms: group 1:-3SD deformations only; group 2: one-4SD deformation; group 3: two-four-4SD deformations; and group 4: 5 or more-4SD deformations. There were no significant differences between the groups. Results were compared with those from 80 premenopausal (average age 32 years, range 20–40 years) and 109 postmenopausal normal women (average age 64, range 60–70 years). Mean BMD in osteoporotic group 1 was lower than premenopausal normal women by 32% at the lumbar spine, 31% femoral neck, 30% trochanteric region, and 44% at Ward's triangle, and postmenopausal controls by 17% lumbar spine, 16% femoral neck, 17% trochanter, and 14% Ward's triangle. There was a clear trend to reduction in mean BMD between osteoporotic groups 1 and 4 at all four measured sites with significant differences at the spine of 0.102 g/cm² (P<0.01) and Ward's triangle 0.059 g/cm² (P<0.01). When compared with premenopausal controls, there was a reduction in mean BMD between osteoporotic groups 1 and 4 of 10% at the lumbar spine, 7% femoral neck, 8% trochanteric region, and 13% Ward's triangle. Receiver operating characteristic analysis showed no significant differences in diagnostic sensitivities among the four measured sites for vertebral fractures. We conclude from this crosssectional data that the majority of bone loss in spinal osteoporosis occurs before the onset of fractures.