Characteristics and course of bone mineral densities among fast bone losers in a rural Japanese community: the Miyama Study

The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine.     

Lumbar bone mineral density in very long-term renal transplant recipients: Impact of circulating sex hormones

The influence of circulating sex hormones and gender on the bone mineral density (BMD) in long-term renal transplant recipients needs further investigation. We performed a retrospective analysis of lumbar BMD between 6 years and 20 years after renal transplantation. In 67 patients (47±12 years, 38 male) with a minimum interval of 72 months after transplantation, lumbar BMD measurements (dual energy X-ray absorptiometry) were performed (=complete cohort). Thirty-one patients (=longitudinal cohort) underwent at least three serial BMD measurements (mean follow-up 39±18 months, start at 86±22 months). All patients received prednisolone. In the complete cohort, BMD was significantly reduced in comparison to young healthy (mean T -score –1.33±1.40) and age-matched controls (mean Z -score –0.91±1.45) at 88±31 months ( p <0.05). Osteopenia or osteoporosis were present in two-thirds of patients. In the longitudinal cohort, a mean annual lumbar BMD loss of –0.6±1.9% was detectable equivalent to a –0.03±0.15 reduction of Z -scores per year (regression analysis). Impact of hormonal status: In the complete cohort, postmenopausal status was associated with significantly lower BMD levels compared to men ( p =0.0441). Women and men within the lowest tertile of sex hormone levels (LH, FSH, DHEAS, testosterone, progesterone, estradiol) did not exhibit significant differences in terms of lumbar BMD compared to those in the highest tertile. The mean annual bone loss was statistically indistinguishable between men and women. There was no significant correlation of sex hormone levels and BMD in men and premenopausal women. In postmenopausal women, however, low estradiol and high LH levels correlated with the extent of annual BMD loss ( p <0.05). Our data confirm significantly reduced lumbar T -scores in the very late period after renal transplantation. The lumbar BMD decreased by –0.6±1.9% per year. In postmenopausal long-term renal transplant recipients, low estradiol levels were associated with accelerated bone loss.The data were presented in part at the 37th annual meeting of the American Society of Nephrology, ASN 2004 (Renal Week 2004)     

Sexual differences in bone markers and bone mineral density of normal Chinese

We measured bone mineral density (BMD) at lumbar (L2–L4) vertebrae and proximal femurs of 385 healthy Chinese women aged 40–70 years and 156 healthy Chinese men aged 20–85, and four markers—bone alkaline phosphatase isozyme (BAP), procollagen-I C terminal propeptide (PICP), osteocalcin (BGP) in serum, and a bone resorption marker, urinary cross-linked N-telopeptide of type I collagen (NTX), of these subjects. The results indicate that in postmenopausal women, levels of all the markers increased with age. In men, serum BAP, PICP, and urinary NTX decreased significantly, and serum BGP decreased with borderline significance (P=0.08). With increasing age, bone density decreased at both sites in post-menopausal women and at the proximal femur in men. The lumbar bone density showed no significant age-related changes in men. In premenopausal women, BMD at either site showed no significant change with increasing age. Despite the different trends between men and women of agerelated changes in BMD and bone markers, bone density of both proximal femur and spine in both sexes correlated inversely with levels of the bone markers in a manner independent of age or body weight. The meaning of opposite age effects on bone markers in men and women needs further investigation. In addition, higher bone marker levels, implying faster bone turnover rate, are associated with lower BMD in both sexes.     

Prevalence of osteoporosis and reference data for lumbar spine and hip bone mineral density in a Korean population

The aims of this study were to establish reference data for bone mineral density (BMD) at central skeletal sites using Lunar dual-energy X-ray absorptiometry (DXA), and to estimate the age-and sex-specific prevalence of osteoporosis in a Korean population. We performed a population-based, cross-sectional study. The subjects were 4148 (1810 men and 2338 women) Korean adults, aged 20–79 years. The BMD for central sites (lumbar spine, femoral neck, trochanter, and Ward’s triangle) were measured by DXA. The standardized prevalence of osteoporosis among individual aged 50–79 years in lumbar spine, femoral neck, Ward’s triangle, and trochanter was 40.1%, 12.4%, 28.4%, and 4.4% in women and 6.5%, 5.9%, 3.7%, and 1.6% in men, respectively. In women, peak BMD occurred in the age range 40–49 years for the femoral neck and trochanter, 30–39 years for the lumbar spine, and 20–29 years for Ward’s triangle. In men, peak BMD values were observed at 20–29 years for all measured sites. This study establishes a normative database for BMD at central skeletal sites using dualenergy X-ray absorptiometry and provides more reliable information on the prevalence of osteoporosis in Korea.     

Determinants of Bone Loss in a Rural Japanese Community: The Taiji Study

The objective of this study was to assess the rate of bone loss and characterize its determinants, among the inhabitants of Taiji, a rural Japanese community. A cohort of 2261 inhabitants aged 40–79 years was established using resident registration in 1992. Fifty men and 50 women in each of four age strata between 40 and 79 years were randomly selected and completed a self-administered risk factor questionnaire. Baseline bone density of lumbar spine and proximal femur was measured by dual-energy X-ray absorptiometry in 1993. BMD was measured again on the same participants in 1996. The rates of change of lumbar spine BMD in men in their 40s, 50s, 60s and 70s were 0.20%, 0.34%, 0.43% and 0.28% respectively. Rates in women were –0.35%, –1.02%, –0.10% and –0.20% respectively. At the femoral neck, rates of change in BMD among men in their 40s, 50s, 60s and 70s were 0.09%, –0.07%, 0.34% and 0.31% respectively. Femoral neck rates of change among women were –0.55%, 0.02%, 0.49% and –0.25% respectively. The rate of change of lumbar spine BMD was –0.24% in premenopausal women with regular periods, –1.99% in premenopausal women with irregular periods and –0.33% in postmenopausal women. Anthropometric measurements at baseline were also related significantly to change in bone density. Baseline weight and height were statistically significant predictors of bone loss rate.These data provide estimates of the rate of bone loss among Japanese men and women aged 40– 79 years. They suggest that body build and menstrual function in women are important determinants of bone loss. Received: 20 November 1997 / Revised: 1 April 1998     

Osteoporosis: prevalence in Taiwanese women

The aim of this study is to understand the current status of bone mineral density (BMD) among Taiwanese women and to determine the relationship between bone mass, weight, height and body mass index (BMI), and the proportion of osteoporosis sufferers, based on World Health Organization standards, in each age group. A total of 4689 women underwent lumbar vertebrae (L2–L4) BMD measurements, and 3529 women underwent femoral neck bone mineral density measurements. BMD was measured using dual-energy X-ray absorptiometry. Standards were based on the BMD of the 20- to 40-year-old age group, as were relationships between height, weight, BMI, and BMD. Pearson correlation revealed a positive relationship between body weight, BMI, and BMD in the femoral neck; other correlations were insignificant. The defined BMD value for a diagnosis of osteoporosis was 0.827 g/cm² for lumbar vertebrae and 0.605 g/cm² for the femoral neck. The proportion of osteoporosis calculated for each age group in the lumbar vertebrae group was: 40–49 years old, 8.25%; 50–59 years old, 8.62%; 60–69 years old, 14.14%; 70–79 years old, 14.25%; >80 years old, 16.07%. For the femoral neck group, the values were: 40–49 years old, 5.24%; 50–59 years old, 5.28%; 60–69 years old, 11.17%; 70–79 years old, 17.30%; >80 years old, 24%. The total proportion of osteoporosis in the lumbar vertebrae was 10.08%, and in the femoral neck, 7.45%. The BMD of Taiwanese women shows a positive relationship to body weight and BMI in the femoral neck group but not in the lumbar vertebrae group. The proportion of osteoporosis by age group in this cohort was lower than that among Western women.     

Effects of high-impact exercise on bone mineral density: a randomized controlled trial in premenopausal women

Introduction: The purpose of this randomized controlled study was to assess the effects of high-impact exercise on the bone mineral density (BMD) of premenopausal women at the population level. Materials and methods: The study population consisted of a random population-based sample of 120 women from a cohort of 5,161 women, aged 35 to 40 years. They were randomly assigned to either an exercise or control group. The exercise regimen consisted of supervised, progressive high-impact exercises three times per week and an additional home program for 12 months. BMD was measured on the lumbar spine (L1–L4), proximal femur, and distal forearm, by dual-energy X-ray absorptiometry at baseline and after 12 months. Calcaneal bone was measured using quantitative ultrasound. Results: Thirty-nine women (65%) in the exercise group and 41 women (68%) in the control group completed the study. The exercise group demonstrated significant change compared with the control group in femoral neck BMD (1.1% vs –0.4%; p=0.003), intertrochanteric BMD (0.8% vs –0.2%; p=0.029), and total femoral BMD (0.1% vs –0.3%; p=0.006). No exercise-induced effects were found in the total lumbar BMD or in the lumbar vertebrae L2–L4. Instead, L1 BMD (2.2% vs –0.4%; p=0.002) increased significantly more in the exercise group than in the control group. Calcaneal broadband ultrasound attenuation showed also a significant change in the exercise group compared with the control group (7.3% vs –0.6%; p=0.015). The changes were also significant within the exercise group, but not within the control group. There were no significant differences between or within the groups in the distal forearm. Conclusions: This study indicates that high-impact exercise is effective in improving bone mineral density in the lumbar spine and upper femur in premenopausal women, and the results of the study may be generalized at the population level. This type of training may be an efficient, safe, and inexpensive way to prevent osteoporosis later in life.     

Gender differences in trabecular bone architecture of the distal radius assessed with magnetic resonance imaging and implications for mechanical competence

High-resolution magnetic resonance imaging (hrMRI) has recently made it possible to evaluate trabecular bone structure in vivo. Despite obvious gender differences in fracture incidence at the distal radius, little is known about gender differences in trabecular bone microarchitecture and its relationship to the structural strength of the forearm. The aim of this study was to determine trabecular bone structure in the distal radius of elderly women and men and its correlation with failure loads of the distal radius as determined in a fall configuration. Specifically, we tested the hypotheses that structural indices differ between women and men and that they offer information that is independent from BMD for predicting structural strength. Intact right arms were obtained from 73 formalin-fixed cadavers (age 80±11 years, 43 women, 30 men). Trabecular structural indices (apparent bone volume fraction [app. BV/TV], trabecular number [app. Tb.N], trabecular separation [app. Tb.Sp], trabecular thickness [app. Tb.Th] and fractal dimension [Frac.Dim]) were assessed in the distal metaphysis, using hrMRI with 156 µm in-plane resolution and proprietary digital image analysis, while BMD was measured with dual X-ray absorptiometry (DXA). Women displayed significantly lower BMD (–29.8%, p <0.001), app. BV/TV (–8.2%, p <0.05) and app. Tb.Th (–10.2%, p <0.001) than men, whereas app. Tb.N, app. Tb.Sp. and fractal dimension did not differ significantly. Structural parameters differed between normal and osteopenic women (BV/TV: –11%, p <0.01; Tb.Th: –8%, p <0.001) and between normal and osteoporotic women BV/TV: –21%, p <0.001; Tb.Th: –16%, p <0.001). App. BV/TV, app. Tb.Th and fractal dimension provided information independent from BMD in the prediction of radial failure loads in multiple regression models. These findings imply that it should be of clinical interest to monitor both bone mass and trabecular microstructure for predicting osteoporotic fracture risk.     

Effect of walking exercise on bone metabolism in postmenopausal women with osteopenia/osteoporosis

The purpose of this prospective study was to determine whether moderate walking exercise in postmenopausal women with osteopenia/osteoporosis would affect bone metabolism. Fifty postmenopausal women, aged 49–75 years, with osteopenia/osteoporosis were recruited: 32 women entered the exercise program (the exercise group) and 18 served as controls (the control group). The exercise consisted of daily outdoor walking, the intensity of which was 50% of maximum oxygen consumption, with a duration of at least 1h with more than 8000 steps, at a frequency of 4 days a week, over a 12-month period. Lumbar (L2–L4) bone mineral density (BMD) was measured at the baseline and every 6 months with dual-energy X-ray absorptiometry (DXA) in both groups. Serum bone-specific alkaline phosphatase (BAP) and urinary cross-linked N-terminal telopeptides of type I collagen (NTX) levels were measured at baseline and at months 1, 3, 6, 9, and 12 by EIA and ELISA, respectively, in the exercise group, and urinary NTX level was measured at the baseline and every 6 months in the control group. There were no significant differences in baseline characteristics including age, height, body weight, bone mass index, years since menopause, lumbar BMD, and urinary NTX level between the two groups. Although no significant changes were observed in lumbar BMD and the urinary NTX level in the control group, lumbar BMD in the exercise group was increased as compared with the control group, but was sustained from the baseline. In the exercise group, the urinary NTX level rapidly responded to walking exercise from month 3, and this reduction was sustained until month 12, followed by reduction in the serum BAP level. A moderately negative correlation was found between the percent change in the urinary NTX level at month 3 and that in lumbar BMD at month 12 in the exercise group. This study clearly demonstrates that the mechanism for the positive response of lumbar BMD to moderate walking exercise in postmenopausal women with osteopenia/osteoporosis appears to be the suppression of bone turnover, and that an early change in the urinary NTX level may be useful to predict the long-term response of increasing lumbar BMD to exercise, although its efficacy for lumbar BMD may be quite modest.     

Bone mineral density and osteoporosis among a predominantly Caucasian elderly population in the city of São Paulo, Brazil

This cross-sectional study covered 301 individuals over 70 years of age—207 women (W) and 94 men (M)—living in the city of São Paulo, Brazil. Our aims were to evaluate the prevalence of low bone mineral density (BMD) in this population and the possible factors that influence BMD. The subjects were submitted to a bone densitometry scan (DXA) to evaluate the BMD at lumbar spine (LS), femoral neck (FN), trochanter (T), total femur (TF) and total body composition. At the time, the participants filled in a questionnaire about lifestyle habits, diet and medical history, as well as having blood samples taken to check hormone and biochemical levels. Anthropometric parameters were measured. Osteopenia and osteoporosis were defined in accordance with the criteria suggested by the World Health Organization. In the different sites studied, the prevalence of osteopenia and osteoporosis varied, in men ranging 33.3–57.4% and 6.4–16.1%, respectively, and in women ranging 36.6–56.5% and 22.2–33.2%, respectively. Weight was the variable that most strongly correlated with BMD at the proximal femur in both sexes (men, r =0.44–0.52; women, r =0.48–0.52) and with BMD at LS in women ( r =0.44). Height was the parameter that best correlated with BMD at LS in men ( r =0.34). In men follicle-stimulating hormone, growth hormone and glycemia correlated with BMD at T and TF, while plasma albumin only correlated with BMD at T. In women glycemia correlated with BMD at LS, and follicle-stimulating hormone correlated with BMD at FN, T and TF. In conclusion, we found a high prevalence of osteopenia and osteoporosis in this population, with weight being the best predictor of BMD. The prevalence of osteoporosis and osteopenia at FN was as high in men as that observed in women.     

Measurements of postmenopausal bone loss with a new contact ultrasound system

Summary Measurements of broadband ultrasonic attenuation (BUA) and velocity of ultrasound through the heel (heel velocity, HV) were performed with a Contact Ultrasonic Bone Analyzer (CUBA-Research model) in 229 women. The subjects consisted of 16 healthy young volunteers (Group 1, mean age 26 years), 170 healthy pre- and postmenopausal women (Group 2, mean age 53 years), and 43 osteoporotic women with radiographically defined vertebral crush fracture (Group 3, mean age 66 years). Subjects in Group 1 had 10 repeated measurements in a study of short-term precision. Women in Groups 2 and 3 also had dual X-ray absorptiometry (DXA) scans to measure lumbar spine and femoral neck bone mineral density (BMD). The BUA and HV measurements for all 229 women showed a significant correlation (r = 0.75,P < 0.001). The precision study on the subjects in Group 1 gave a root mean square coefficient of variation of 6.3% for BUA and 1.04% for HV. Linear regression analysis gave the following relationship between BUA and age for the 170 normal women in Group 2: BUA = 83.6 – 0.86 (age 40) dB/MHz (r = –0.31,P < 0.001, SEE = 16.3 dB/MHz). The relationship between HV and age was as follows: HV = 1614 – 2.3 (age 40) m/s (r = –0.33,P < 0.001, SEE = 42 m/s). Multivariate regression analysis showed that in addition to age, years since the menopause was also a significant factor in determining both BUA and HV. In the first 5 years following the menopause, BUA and HV decreased by 2.2% and 0.3%/year, respectively, whereas in the next 10 years the rates of decrease fell to 0.5% and 0.03%/year. The BUA and HV measurements on the 43 osteoporotic subjects in Group 3 gave mean T-scores of –2.1 and –1.9 compared with 59 premenopausal women, and mean Z-scores of –1.3 and –0.9 compared with 26 age-matched normal women in Group 2, respectively. In comparison, the lumbar spine and femoral neck DXA measurements in the same subjects gave mean T-scores of –2.9 and –2.1 and mean Z-scores of –1.7 and –1.0, respectively. Lumbar spine BMD gave the best discrimination between women with osteoporotic vertebral fractures and normal subjects. However, the difference between the lumbar spine and BUA Z-scores was not statistically significant. Femoral neck BMD was equivalent to the ultrasound parameters in T-score and Z-score values.     

Baseline BMD and Bone Loss at Distal Radius Measured by Peripheral Quantitative Computed Tomography in Peri- and Postmenopausal Hong Kong Chinese Women

The current study was designed to investigate the rate of bone loss in distal radius and its association with baseline volumetric bone mineral density (BMD) and years since menopause (YSM) in peri- and postmenopausal women using precise and multislice peripheral quantitative computed tomography (pQCT; Densiscan 2000). Two hundred and five healthy Hong Kong Chinese perimenopausal (n = 26) and postmenopausal (n = 179) women within 10 years of the onset of menopause were recruited. Anthropometric parameters and menstrual status were also measured. The linear regression model derived from the baseline volumetric BMD revealed a significant and slightly better correlation with YSM than age, with a YSM-related annual decline of 2.56%, 1.82% and 0.65% in trabecular BMD (tBMD), integral BMD (iBMD) and cortical BMD (cBMD), respectively. Follow-up measurements after a time interval of 12 months showed that the rate of bone loss was higher than the annual decline in BMD calculated from the baseline BMD, with decreases of 2.89%, 2.16% 0.91% in tBMD, iBMD and cBMD, respectively. Baseline BMD was associated with age or YSM (r ranges from −0.283 to −0.502; p<0.001 in all cases), but no relationship was found between annual rate of bone loss and age or YSM. The rate of bone loss did not correlate with baseline volumetric BMD values or YSM after dividing the subjects into fast bone losers (with annual tBMD loss ≥3%), normal bone losers (with annual tBMD loss ≥ 1% but <3%) or slow bone losers (with annual tBMD loss <1%). The rate of bone loss was greater in both trabecular and cortical bone of postmenopausal women within the first 3 menopausal years but was only significant in the iBMD as compared with perimenopausal and postmenopausal women over 7 years after onset of menopause. The percentage distribution of slow and fast bone losers was not found to be associated with YSM. As a total of only 4 fracture cases were documented, the study could not provide conclusive information on whether perimenopausal and early postmenopausal baseline volumetric BMD or rate of bone loss determines the development of osteoporosis or fracture occurrence. Received: 12 November 2001 / Accepted: 18 July 2002     

Effect of osteoarthritis in the lumbar spine and hip on bone mineral density and diagnosis of osteoporosis in elderly men and women

To determine in the elderly the effect of osteoarthritis on bone mineral density (BMD) and on diagnosis of osteoporosis, lumbar spine and hip were radiographed and BMD measured by dual-energy X-ray absorptiometry (DXA) in 120 men and 314 women, aged 60–99 years. Prevalence and severity of osteoarthritis were scored on osteophytes, joint space narrowing and bone sclerosis. Ultrasound measurements were also made at the heel to examine whether osteoarthritis at hip or lumbar spine influence bone at this remote site. Osteophytes were the commonest feature, with men having a higher prevalence than women, and lumbar spine having more disease than hip. Lumbar spine osteophytes affected 75% of men and 61.1% of women, and hip osteophytes affected 31.7% of men and 27.4% of women. Stepwise multiple regression analysis using age, weight, height, osteophytes, sclerosis and joint space narrowing indicated that lumbar osteophytes explained 16.6% of variation in lumbar spine BMD in women, and 22.4% in men. Hip osteophytes had a minimal effect on hip BMD, accounting for only 2.2% of variation in women, and none in men. Sclerosis and joint narrowing had little effect on BMD at lumbar spine or hip. Indirect effects of osteoarthritis on BMD were small and inconsistent across genders. Lumbar spine osteophytes in men explained 3.1% of hip BMD variation and 6% of variation in speed of sound at the heel, whereas hip osteophytes in women explained 2.2% of lumbar spine BMD variation. Osteoporosis at the hip, defined as BMD <2.5 SD of the young normal mean, was present in 33.1% of women and 25.8% of men, whereas, at the lumbar spine it was present in only 24.2% of women and 4.2% of men. However, in women and men free of spinal osteoarthritis, 37.7% of women and 10% of men had osteoporosis. We conclude that lumbar spine ostoephytes affect most subjects over the age of 60 years, and contribute substantially to lumbar spine BMD measured in the anteroposterior position by DXA. The effect is largely direct by virtue of osteophytes being included in the BMD measurement. However, a small indirect effect on remote skeletal sites is also present. Diagnosis of osteoporosis and assessment of osteoporotic fracture risk in the elderly should be based on hip BMD and not on anteroposterior lumbar spine, unless spinal osteoarthritis has been excluded.     

Metacarpal index and bone mineral density in healthy African-American women

Bone mineral density (BMD) reference data of non-Caucasian women is scarce but greatly needed for African-American women. The objective of this study was to establish a metacarpal normative reference database for African-American women using digital X-ray radiogrammetry (DXR) and hand radiographs and compare these values to existing Caucasian data. Two hundred and fifty healthy African-American women between the ages of 20 and 79 years old, 14 of whom were excluded, were recruited to participate from four different clinical sites. The study population was recruited in approximately equal number into the following groups: 20–29, 30–39, 40–49, 50–59, 60–69 and 70–79 years of age. A radiograph was acquired of each subjects non-dominant hand. The radiographs were scanned and analyzed using radiogrammetric techniques, and the BMD, MCI (Metacarpal Index), bone width and cortical thickness were calculated. The regression curve that best fit the data was a second order polynomial. The BMD and MCI of young adult women (20–40 years of age) were used to calculate T-score parameters. The young reference BMD and MCI with their associated standard deviations were found to be 0.6045 g/cm²±0.0529 g/cm² and 0.5096 and 0.0792, respectively. However, the MCI was found to be approximately 2.5% lower (–0.0118) compared to Caucasian women. The African-American metacarpal BMD was found to be 3.5% (0.0207 g/cm²) higher across all ages when compared to existing Caucasian reference data acquired in a similar way. The differences were found to be entirely due to larger bone size, cortical diameter and bone width in the African-American women.J.A. Shepherd and M. Meta (ex-aequo) contributed equally to this work.     

Bone metabolic marker levels in residents of a rural community in Japan

The sex and age distributions of values of bone metabolic markers were investigated among the inhabitants of a mountain village in Wakayama Prefecture, Japan. The survey was carried out in Miyama village, which has a population of 2372 (1129 men and 1243 women) based on the resident registration of 1990. In this village, all residents aged 40 years or over are eligible for general mass health examinations once a year. In the present study, bone metabolic markers were measured in recruited participants in the health examinations conducted in 1992 in each of four age strata: 40–49, 50–59, 60–69, and 70–79 years. The bone metabolic markers measured were osteocalcin (BGP), carboxyterminal peptide of type I procollagen (PICP), alkaline phosphatase (ALP), crosslinked carboxyterminal telopeptide region of type I collagen (ICTP), pyridinoline (Pyr), and deoxypyridinoline (D-Pyr). In men in their 40s, 50s, 60s, and 70s, the mean serum BGP level was 6.15, 7.04, 7.65, and 7.69 ng/ml, respectively; the level in men in their 40s was significantly lower than that in those in their 60s. The serum PICP level in the 40- to 49-year age group was significantly higher than those in the other age groups, while that of serum ICTP tended to increase with age. The mean values of urinary Pyr and D-Pyr were higher in the older groups. In women, the mean values of all bone metabolic markers were all higher among those in the 50–59, 60–69, and 70–79 age groups compared to those in the 40–49 age group. These findings suggest that active bone metabolic turnover occurs even in the older age groups in both men and women.     

Leptin predicts BMD and bone resorption in older women but not older men: the Rancho Bernardo study.

We studied the relation of leptin to bone, bone loss, and bone turnover in community-dwelling men and women. Leptin predicted higher BMD and lower bone turnover only in women. Leptin was not associated with 4-year bone loss in either sex. INTRODUCTION: Leptin, the protein product of the obesity (OB) gene produced in fat tissue, was originally thought to be involved only in the regulation of food intake and energy balance. Recent evidence suggests that leptin may play a role in the pathophysiology of several chronic diseases. Studies of the association between leptin and bone have been numerous yet inconclusive. Only one previous longitudinal study has been reported, which showed no association of leptin with BMD after adjusting for body size. MATERIALS AND METHODS: We report the association of serum leptin with BMD at the hip, spine, and midshaft radius in community-dwelling men (n = 498) and nonestrogen-using postmenopausal women (n = 411) 45-92 years of age. Serum leptin was measured in blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA; at the same visit, height, weight, and body fat (by bioelectrical impedance analysis) were measured, and bone resorption was assessed in a subset of men (n = 286) and women (n = 241) using urine N-telopeptide (NTX). Four years later, axial BMD was remeasured in 536 participants. Sex-specific associations of leptin with BMD, NTX, and bone loss were tested using regression analysis. RESULTS: In unadjusted analyses, leptin was associated with BMD at the femoral neck, total hip, lumbar spine, and midshaft radius in both sexes (p < 0.01). In multiple regression analyses, adjusted for age, BMI, and other bone-related factors, only women showed a graded stepwise positive association between serum leptin and BMD at all sites and a negative stepwise association with NTX (all p for trend < 0.01). Baseline leptin levels did not predict 4-year bone loss in either sex. CONCLUSIONS: A favorable dose-dependent leptin-BMD association unexplained by obesity was observed only in women. The reason for the sex difference is unknown.     

Age, body mass index, current smoking history, and serum insulin-like growth factor-I levels associated with bone mineral density in middle-aged Korean men

Osteoporosis is a growing health problem in women and in men. This cross-sectional study examined the association of anthropometric, lifestyle, and hormonal factors with bone mineral density (BMD) in 152 healthy Korean middle-aged men. Smoking habits and alcohol consumption were assessed by interview. Serum testosterone and insulin-like growth factor-I (IGF-I) levels were measured by radioimmunoassay, and serum growth hormone (GH) levels were measured by immunoradiometric assay. GH stimulation tests were performed after the ingestion of 500mg of L-dopa. BMD was measured at the lumbar spine and at the femoral neck by dual-energy X-ray absorptiometry. Of the middle-aged men, 3.9% were osteoporotic and 28.3% were osteopenic at the lumbar spine site, and 5.9% were osteoporotic and 45.4% were osteopenic at the femoral neck site. Lumbar spine BMD correlated significantly with body mass index (BMI), and femoral neck BMD correlated significantly with age, BMI, and serum IGF-I levels. The lowest quartile group for serum IGF-I levels showed the lowest femoral neck BMD. Osteoporotic men by lumbar spine BMD showed significant differences from the normal BMD group in terms of BMI and smoking habits. Also, osteoporotic men by femoral neck BMD were significantly different for mean age, BMI, and serum IGF-I levels compared with the normal BMD group. On multiple regression analysis, BMI was found to be the only independent predictor of lumbar spine BMD, whereas both BMI and serum IGF-I levels were found to be the independent predictors of femoral neck BMD. Overall, 28.3%–45.4% of middle-aged Korean men were osteopenic. We suggest that higher age, a lower BMI, current smoking history, and lower serum IGF-I levels are risk factors for lower BMD in middle-aged Korean men; however, serum testosterone levels and GH secretory capacity were not found to be correlated with BMD.     

Skipping breakfast and less exercise are risk factors for bone loss in young Japanese adults: a 3-year follow-up study

Although bone loss contributes to osteoporosis (OP) in the elderly, little is known about changes in bone mineral density (BMD) in young adults that lead to bone loss. Here, we evaluated the rate of bone change and risk factors for bone loss in young men and women using data from a 3-year prospective study of Japanese medical students. The study included a self-administrated questionnaire survey, anthropometric measurements, and BMD measurements of the spine (L2–L4) and femoral neck (FN). After 3 years, the BMD of the participants was again measured at the same sites. In all, 458 students (95.4 %; 298 men and 160 women; age range, 18–29 years; mean age, 20.2 years) completed both the baseline and follow-up surveys. The mean L2–L4 BMD value at baseline increased significantly within 3 years. This tendency was also observed for the FN in men but not in women. The annual changes at L2–L4 were 1.78 % in men and 0.97 % in women per year; those for FN were 1.08 % in men and 0.08 % in women per year. However, 20.3 % and 38.5 % of the total freshmen lost BMD in the lumbar spine and FN, respectively. After adjustment for age and body mass index, logistic regression analysis revealed that bone loss in men at L2–L4 at the baseline was affected by skipping breakfast. In contrast, exercise (>2 h/week) increased lumbar spine BMD in both genders. These findings indicate that breakfast and exercise are important for maintaining BMD in young men and women.     

Forearm bone mineral density in an unselected population of 2,779 men and women—The HUNT Study, Norway

The fracture incidence in Norway is among the highest in Europe, presumably due to osteoporosis. As part of a multipurpose health study in the county of Nord-Trøndelag, Norway (the HUNT study), a 5% randomly selected sample (n=4,646) of the population >19 years of age was invited to undergo single X-ray absorptiometry (SXA) of the forearm. A total of 1,274 men (50.5 years) and 1,505 women (49.9 years) participated (60%). The aim of the study was to describe the variation in bone mineral density (BMD) and the prevalence of forearm BMD 2.5 standard deviations (SD) below the mean value for young adults in an unselected population sample. In women the BMD remained stable until the age of 50 years, whereupon a strong decline in BMD was observed. In men, a BMD increase was observed until about the age of 40 years; the decline after the age of 65 was, however, similar to that in women. Based on age and gender-specific reference values, the age-adjusted prevalence of T-scores <–2.5 SD in women and men aged 50–69 years was 16.0% and 5.6%, respectively. In the age group of 70 years or older the prevalence was 65.8% and 30.6% for women and men, respectively. The accelerated BMD reduction in women aged 50–65 explains the higher prevalence of T-score <–2.5 SD in elderly women than in men. Further studies on bone loss and falls are required to explain the high fracture incidence in Norway.     

Risk factors associated with peri- and postmenopausal bone loss: does HRT prevent weight loss-related bone loss?

 In the present study we evaluated the risk factors associated with peri- and postmenopausal bone loss and the effect of hormone replacement therapy (HRT) on weight-loss-related bone loss. The study population, 940 peri- and postmenopausal women, was selected from a random sample (n = 2025) of the OSTPRE study cohort (n = 13 100) in Kuopio, Finland. Bone mineral density (BMD; g/cm²) at the lumbar spine and femoral neck, and body weight, were measured at baseline in 1989–91 and at 5-year follow-up in 1994–97 by trained personnel. Five hundred and forty-seven women had never used HRT and 393 women used part-time or continuous HRT during follow-up of 3.8–7.9 years (mean 5.8 years). Similarly, of the 172 weight losers, 97 had never used HRT while 75 used it during follow-up. According to multiple regression analysis on the total study population (n = 940), HRT use, years since menopause and weight increase significantly predicted lower annual bone loss at both the lumbar spine and femoral neck (p < 0.005). Low baseline weight and higher age predicted higher bone loss only at the lumbar spine (p < 0.001) and high grip strength predicted lower bone loss only at the femoral neck (p = 0.021). In a sub-analysis on weight losers, weight loss predicted greater bone loss in HRT non-users (p < 0.05), whereas this was not observed in HRT users. These results remained similar after adjustment for age, weight, height, calcium intake, duration of menopause, baseline BMD and bone-affecting diseases/medication. In conclusion, the transition to menopause, HRT and weight change are the most important determinants of bone loss at both the lumbar spine and femoral neck. Furthermore, HRT seems to be effective in prevention of weight loss related bone loss. Received: 29 March 2002 / Accepted: 26 August 2002