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Areal BMD (aBMD) from DXA is not a sufficiently accurate predictor of fracture. Novel volumetric BMD derived from 3D modeling of the hip from DXA images significantly improved the predictive ability for hip fracture relative to aBMD at the femoral neck, but not aBMD at the total hip. To clarify whether volumetric and geometric indices derived from novel three-dimensional (3D) modeling of the hip using dual-energy X-ray absorptiometric (DXA) images improve hip fracture prediction relative to areal bone mineral density (aBMD). We examined 1331 women who had completed the baseline survey and at least one follow-up survey over 20 years (age 40–79 years at baseline). Each survey included aBMD measurement at the hip by DXA. Volumetric and geometric indices of the hip at baseline and the 10-year follow-up were estimated from DXA images using a 3D modeling algorithm. Incident hip fractures during the 20-year follow-up period were identified through self-report. Cox proportional hazards regression models allowing for repeated measurements of predictors and outcomes were constructed, and their predictive ability for hip fracture was evaluated using areas under receiver operating characteristic curves (AUCs) and net reclassification improvement (NRI) over aBMD at the femoral neck (FN) and total hip (TH) as references. During a median follow-up of 19.8 years, 68 incident hip fractures were identified (2.22/1000 person-years). A significantly larger AUC of trabecular volumetric BMD (vBMD) at the total hip (AUC = 0.741), femoral neck (AUC = 0.748), and intertrochanter (AUC = 0.738) and significant NRI (0.177, 0.149, and 0.195, respectively) were observed compared with FN-aBMD (AUC = 0.701), but not TH-aBMD. vBMD obtained from 3D modeling using routinely obtained hip DXA images significantly improved hip fracture risk prediction over conventional FN-aBMD, but not TH-aBMD. The Japanese Population-Based Osteoporosis (JPOS) Cohort Study was retrospectively registered as UMIN000032869 in the UMIN Clinical Trials Registry on July 1, 2018.

Background The Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) study was launched to investigate risk factors for osteoporotic fractures, interactions of osteoporosis with other non-communicable chronic diseases, and effects of fracture on QOL and mortality. Methods FORMEN baseline study participants (in 2007 and 2008) included 2012 community-dwelling men (aged 65–93 years) in Nara prefecture, Japan. Clinical follow-up surveys were conducted 5 and 10 years after the baseline survey, and 1539 and 906 men completed them, respectively. Supplemental mail, telephone, and visit surveys were conducted with non-participants to obtain outcome information. Survival and fracture outcomes were determined for 2006 men, with 566 deaths identified and 1233 men remaining in the cohort at 10-year follow-up. Comments The baseline survey covered a wide range of bone health-related indices including bone mineral density, trabecular microarchitecture assessment, vertebral imaging for detecting vertebral fractures, and biochemical markers of bone turnover, as well as comprehensive geriatric assessment items. Follow-up surveys were conducted to obtain outcomes including osteoporotic fracture, cardiovascular diseases, initiation of long-term care, and mortality. A complete list of publications relating to the FORMEN study can be found at https://www.med.kindai.ac.jp/pubheal/FORMEN/Publications.html.

Background Body mass-independent parameters might be more appropriate for assessing cardiometabolic abnormalities than weight-dependent indices in Asians who have relatively high visceral adiposity but low body fat. Dual-energy X-ray absorptiometry (DXA)-measured trunk-to-peripheral fat ratio is one such body mass-independent index. However, there are no reports on relationships between DXA-measured regional fat ratio and cardiometabolic risk factors targeting elderly Asian men. Methods We analyzed cross-sectional data of 597 elderly men who participated in the baseline survey of the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) study, a community-based single-center prospective cohort study conducted in Japan. Whole-body fat and regional fat were measured with a DXA scanner. Trunk-to-appendicular fat ratio (TAR) was calculated as trunk fat divided by appendicular fat (sum of arm and leg fat), and trunk-to-leg fat ratio (TLR) as trunk fat divided by leg fat. Results Both TAR and TLR in the group of men who used ≥ 1 medication for hypertension, dyslipidemia, or diabetes (“user group”; N = 347) were significantly larger than those who did not use such medication (“non-user group”; N = 250) (P < 0.05). After adjusting for potential confounding factors including whole-body fat, both TAR and TLR were significantly associated with low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, fasting serum insulin, and the insulin resistance index in the non-user group and non-overweight men in the non-user group (N = 199). Conclusion The trunk-to-peripheral fat ratio was associated with cardiometabolic risk factors independently of whole-body fat mass. Parameters of the fat ratio may be useful for assessing cardiometabolic risk factors, particularly in underweight to normal-weight populations.

There are conflicting reports on whether muscle strength is associated with bone mineral density (BMD) independently of muscle mass. Here, we examined the association between muscle strength and BMD in a representative population of Japanese women. Cross-sectional data from 680 postmenopausal women, who were participants in the 15th-year follow-up survey of the Japanese Population-based Osteoporosis cohort study, were analyzed. Areal BMD (aBMD) at the femoral neck and lumbar spine, whole-body bone mineral density, and appendicular skeletal muscle mass (ASM, kg) were measured by dual-energy X-ray absorptiometry. The ASM index (ASMI, kg/m2) was calculated as ASM divided by height squared (m2). Grip strength (kg) was measured as an indicator of muscle strength. Grip strength showed significantly (P

FRAX® is widely used to evaluate fracture risk of individuals in clinical settings. However, FRAX® prediction accuracy is not sufficient, and improvement is desired. Trabecular bone score, a bone microarchitecture index, may improve FRAX® prediction accuracy for major osteoporotic fractures in community-dwelling elderly Japanese men. To improve fracture risk assessment in clinical settings, we evaluated whether the combination of FRAX® and Trabecular Bone Score (TBS) improves the prediction accuracy of major osteoporotic fractures (MOFs) in elderly Japanese men compared to FRAX® alone. Two thousand and twelve community-dwelling men aged ≥65 years completed the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Baseline Study comprising lumbar spine (LS) and femoral neck areal bone mineral density (aBMD) measurements, and interviews regarding clinical risk factors required to estimate 10-year risk of MOF (hip, spine, distal forearm, and proximal humerus) using the Japanese version of FRAX® (v.3.8). TBS was calculated for the same vertebrae used for LS-aBMD with TBS iNsight software (v.2.1). MOFs that occurred during the follow-up period were identified by interviews or mail and telephone surveys. Prediction accuracy of a logistic model combining FRAX® score and TBS compared to FRAX® alone was evaluated by area under receiver-operating characteristic curves (AUCs), as well as category-free integrated discrimination improvement (IDI) and net reclassification improvement (NRI). We identified 22 men with MOFs during 8140 person-years (PY) of follow-up among 1872 men; 67 men who suffered from fractures other than MOFs were excluded. Participants with MOFs had significantly lower TBS (p = 0.0015) and higher FRAX® scores (p = 0.0089) than those without. IDI and NRI showed significant improvements in reclassification accuracy using FRAX® plus TBS compared to FRAX® alone (IDI 0.006 (p = 0.0362), NRI 0.452 (p = 0.0351)), although no difference was observed in AUCs between the two. TBS may improve MOF prediction accuracy of FRAX® for community-dwelling elderly Japanese men.

Recent animal studies have demonstrated that undercarboxylated osteocalcin upregulates insulin secretion via osteoblast-insulin signaling. However, it remains unclear whether such a pathway exists in humans. This study showed that serum undercarboxylated osteocalcin levels were inversely associated with fasting plasma glucose, hemoglobin A(1c), and homeostasis model assessment of insulin resistance (HOMA-IR) levels in community-dwelling elderly Japanese men.Undercarboxylated osteocalcin (ucOC) was reported to increase insulin secretion and improve glucose tolerance via osteoblast-insulin signaling in animal-based studies. Whether this pathway also exists in humans is unknown. We aimed to clarify whether serum ucOC levels are associated with glycemic status and insulin resistance in the general Japanese population.We included 2,174 Japanese men (≥65 years) who were able to walk without aid from others and lived at home in four cities of Nara Prefecture. We excluded participants with a history of diseases or medications that affect bone metabolism, other than type 2 diabetes mellitus (T2DM). Fasting plasma glucose, glycated hemoglobin A(1c), and HOMA-IR levels were determined as outcome measures.Of the 1,597 participants included in the analysis, both intact OC (iOC) and ucOC levels showed significant inverse correlations with all outcome measures, even after adjusting for potential confounders. Mean values of outcome measures showed a significant decreasing trend with higher quintiles of iOC or ucOC after adjusting for confounders. This trend remained significant for ucOC quintiles after further adjustment for iOC levels, but was not significant for iOC quintiles after adjusting for ucOC levels. These results were attenuated, but still apparent, after excluding participants receiving drug therapy for T2DM.Levels of ucOC, but not iOC, were inversely associated with glycemic index and insulin resistance in a population of Japanese men. These findings will need to be confirmed with longitudinal studies.

A cross-sectional analysis of 1,662 community dwelling elderly Japanese men suggested that habitual natto intake was significantly associated with higher bone mineral density (BMD). When adjustment was made for undercarboxylated osteocalcin levels, this association was insignificant, showing the natto–bone association to be primarily mediated by vitamin K. Low vitamin K intake is associated with an increased risk of hip fracture, but reports have been inconsistent on its effect on BMD. Our first aim was to examine the association between BMD and intake of fermented soybeans, natto, which contain vitamin K1 (20 μg/pack) and K2 (380 μg/pack). Our second aim was to examine the association between undercarboxylated osteocalcin (ucOC), a biomarker of vitamin K intake, and BMD to evaluate the role of vitamin K in this association. Of the Japanese men aged ≥65 years who participated in the baseline survey of the Fujiwara-kyo Osteoporosis Risk in Men study, 1,662 men without diseases or medications known to affect bone metabolism were examined for associations between self-reported natto intake or serum ucOC levels with lumbar spine or hip BMD. The subjects with greater intake of natto showed significantly lower level of serum ucOC. Analysis after adjustment for confounding variables showed an association of greater intake of natto with both significantly higher BMD and lower risk of low BMD (T-score

Our cross-sectional analysis of 1,576 men aged ≥65 years examined smoking effects on bone status. Number of smoking years was associated with decreased bone mineral density (BMD), after adjusting for age, height, weight, and number of cigarettes smoked daily. Smoking did not affect biochemical marker serum values for bone turnover.The impact of smoking on bone status in men has not been conclusively established. We examined how smoking and its cessation influence bone status and metabolism in men.We analyzed 1,576 men among a baseline survey of Japanese men aged ≥65 years, the Fujiwara-kyo Osteoporosis Risk in Men study, conducted during 2007-2008.Lumbar spine (LS) BMD values among never, former, and current smokers were 1.045 ± 0.194, 1.030 ± 0.189, and 1.001 ± 0.182 g/cm(2) (P = 0.005), respectively, while total hip (TH) BMD values were 0.888 ± 0.120, 0.885 ± 0.127, and 0.870 ± 0.124 (P = 0.078), respectively. The significant trend for LS BMD remained after adjusting for the covariates; age, height, weight, physical activity, milk consumption, and drinking habit (P = 0.036). Among never and ever (current and former) smokers, LS and TH BMD decreased with the number of pack years or the number of smoking years, respectively, adjusted for those covariates. Among ever smokers, LS and TH BMD decreased with the number of smoking years after adjusting for age, height, weight, and number of cigarettes smoked daily. Smoking did not reveal significant effect for serum osteocalcin or tartrate resistant acid phosphatase isoenzyme 5b.The impact of smoking on bone status is mainly associated with the number of smoking years in elderly men.

In Japan, the main source of dioxins is incinerators. This study examined the relationship between the distance of schools from municipal waste incineration plants and the prevalence of allergic disorders and general symptoms in Japanese children. Study subjects were 450,807 elementary school chil- dren aged 6-12 years who attended 996 public ele- mentary schools in Osaka Prefecture in Japan. Parents of school children completed a questionnaire that included items about illnesses and symptoms in the study child. Distance of each of the public ele- mentary schools from all of the 37 municipal waste incineration plants in Osaka Prefecture was measured using geographical information systems packages. Adjustment was made for grade, socioeconomic sta- tus and access to health care per municipality. De- creases in the distance of schools from the nearest municipal waste incineration plant were indepen- dently associated with an increased prevalence of wheeze, headache, stomach ache, and fatigue (adjusted odds ratios (95% confidence intervals) for shortest vs. longest distance categories =1.08 (1.01- 1.15), 1.05 (1.00-1.11), 1.06 (1.01-1.11), and 1.12 (1.08-1.17), respectively). A positive association with fatigue was pronounced in schools within 4 km of the second nearest municipal waste incineration plant. There was no evident relationship between the dis- tance of schools from such a plant and the prevalence of atopic dermatitis or allergic rhinitis. The findings suggest that proximity of schools to municipal waste incineration plants may be associated with an increased prevalence of wheeze, headache, stomach ache, and fatigue in Japanese children.