Bone Mineral Content Levels Research Articles

Auraptene ameliorates osteoporosis by inhibiting RANKL/NFATc1 pathway-mediated bone resorption based on network pharmacology and experimental evaluation.

AimsThe association of auraptene (AUR), a 7-geranyloxycoumarin, on osteoporosis and its potential pathway was predicted by network pharmacology and confirmed in experimental osteoporotic mice.MethodsThe network of AUR was constructed and a potential pathway predicted by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment. Female ovariectomized (OVX) Institute of Cancer Research mice were intraperitoneally injected with 0.01, 0.1, and 1 mM AUR for four weeks. The bone mineral density (BMD) level was measured by dual-energy X-ray absorptiometry. The bone microstructure was determined by histomorphological changes in the femora. In addition, biochemical analysis of the serum and assessment of the messenger RNA (mRNA) levels of osteoclastic markers were performed.ResultsIn total, 65.93% of the genes of the AUR network matched with osteoporosis-related genes. Osteoclast differentiation was predicted to be a potential pathway of AUR in osteoporosis. Based on the network pharmacology, the BMD and bone mineral content levels were significantly (p < 0.05) increased in the whole body, femur, tibia, and lumbar spine by AUR. AUR normalized the bone microstructure and the serum alkaline phosphatase (ALP), bone-specific alkaline phosphatase (bALP), osteocalcin, and calcium in comparison with the OVX group. In addition, AUR treatment reduced TRAP-positive osteoclasts and receptor activator of nuclear factor kappa-B ligand (RANKL)+nuclear factor of activated T cells 1 (NFATc1)+ expression in the femoral body. Moreover, the expressions of initiators for osteoclastic resorption and bone matrix degradation were significantly (p < 0.05) regulated by AUR in the lumbar spine of the osteoporotic mice.ConclusionAUR ameliorated bone loss by downregulating the RANKL/NFATc1 pathway, resulting in improvement of osteoporosis. In conclusion, AUR might be an ameliorative cure that alleviates bone loss in osteoporosis via inhibition of osteoclastic activity.Cite this article: Bone Joint Res 2022;11(5):304–316.

The Association Between Prolonged Proton Pump Inhibitors Use and Bone Mineral Density.

Background and study aimChronic use of proton-pump inhibitors (PPIs) has become a mainstay of therapy in common gastrointestinal diseases. A causal relationship between chronic PPI use and development of osteoporosis remains unproven. The aim of this study was to determine whether PPI users are more likely to develop alterations in bone density.Patients and methodsIn an analytical cross sectional study, patients who used PPIs for more than 2 years because of long-term gastroesophageal reflux disease (GERD) were recruited. PPI users were healthy people except for GERD. The compression group was randomly derived from an age-, sex- and physical activity-matched group from a healthy population in the National Registry of Osteoporosis who had not used PPIs in the previous 2 years. Bone mineral density was measured with dual-energy X-ray absorptiometry. Data regarding BMD and bone mineral content (BMC) of three regions: femoral neck, total hip, and the lumbar spine (L1-L4) were gathered and recorded. The World Health Organization (WHO) classification was used for definition of osteopenia and osteoporosis.ResultsA total of 394 participants (133 PPI users and 261 comparison group) were enrolled. The median duration of PPI use was 6.7 (2–31) years. The mean age ± SD of PPI users and comparison group was 48.38 ± 11.98 and 47.86 ± years, respectively (P = 0.681). There was no significant difference in baseline characteristics and age distribution between the two groups. The BMC levels were significantly lower in PPI users in all three regions: lumbar spine, total hip, and femoral neck (P<0.001). There were no significant differences in the T-scores between the two groups except for femoral neck (P<0.001). Osteoporosis in femoral neck was significantly higher in PPI users than in comparison group.ConclusionThis study showed that long-term use of PPIs is associated with lower BMC and higher rate of osteoporosis in the femoral neck. However, more studies with longitudinal evaluation should be performed to clarify this causal relationship. Until then, it is advised not to overuse PPIs because of the possible increase in risk of osteoporosis and the risk of fractures. We also recommend using the BMC levels as a quantitative measure in addition to T scores in analysis and reporting similar studies.

Improvement of osteoporosis by Lycium chinense administration in ovariectomized mice

BackgroundThe fruit of Lycium chinense (LC), one of the most popular natural materials, has been used to counter the effects of musculoskeletal diseases in oriental medicine. In particular, this fruit is known to have antiaging effects, which is of significant interest to the research community. The purpose of our investigation was to observe and confirm the ameliorative effect of LC on osteoporosis, which was verified in this in vivo study. MethodsFemale ICR mice aged 5 weeks were surgically ovariectomized (OVX) to induce osteoporosis. After 7 weeks of induction, oral administration with 1 mg/kg and 100 mg/kg LC was continued for 6 weeks. At the end of the experiment, the levels of bone mineral content (BMC) and bone mineral density (BMD) were estimated by dual-energy X-ray absorptiometry. Hematoxylin and eosin staining was performed; additionally, serum osteocalcin and calcium concentrations were analyzed. ResultsLC treatment significantly reduced the deterioration of BMC and BMD compared with OVX mice. Histological analysis showed that LC ameliorated osteoporosis including the hypertrophy of the epiphyseal plate. Additionally, decreased serum osteocalcin as well as the calcium levels recovered following the administration of LC. ConclusionThese results demonstrated that LC ameliorates osteoporosis in OVX mice by improving several important parameters including BMC, BMD, and bone-turnover markers such as osteocalcin and calcium levels in serum.

The Effect of Serum Magnesium Levels and Serum Endothelin-1 Levels on Bone Mineral Density in Protein Energy Malnutrition

An inadequate and imbalanced intake of protein and energy results in protein-energy malnutrition (PEM). It is known that bone mineral density and serum magnesium levels are low in malnourished children. However, the roles of serum magnesium and endothelin-1 (ET-1) levels in the pathophysiology of bone mineralization are obscure. Thus, the relationships between serum magnesium and ET-1 levels and the changes in bone mineral density were investigated in this study. There was a total of 32 subjects, 25 of them had PEM and seven were controls. While mean serum ET-1 levels of the children with kwashiorkor and marasmus showed no statistically significant difference, mean serum ET-1 levels of both groups were significantly higher than that of the control group. Serum magnesium levels were lower than normal value in 9 (36%) of 25 malnourished children. Malnourished children included in this study were divided into two subgroups according to their serum magnesium levels. While mean serum ET-1 levels in the group with low magnesium levels were significantly higher than that of the group with normal magnesium levels (p < 0.05), mean bone mineral density and bone mineral content levels were significantly lower (p < 0.05). In conclusion, many factors play a role in the pathophysiology of changes in bone mineral density in malnutrition. Our study suggested that lower magnesium levels and higher ET-1 levels might be important factors in changes of bone mineral density in malnutrition. We recommend that the malnourished patients, especially with hypomagnesaemia, should be treated with magnesium early.

Abstract 422: Relationship Between N-Telopeptide-Mediated Bone Mineral Resorption and Peripheral Arterial Disease

Background: Patients with peripheral arterial disease (PAD) have a higher incidence of hip bone loss and non-spinal fractures independent of their cardiovascular risk or degree of claudication. The mechanisms explaining this excess risk of osteoporosis are poorly understood. N-telopeptide (NTX) is an amino-terminal cross-linked type I collagen peptide that is released during fibrillogenesis, reflecting both the derivative products of bone collagen and bone resorption. When elevated, it serves as an early marker for osteoporosis and predictor of therapeutic response. We hypothesized that patients with PAD have reduced bone mineral content and that PAD is associated with biomarkers of accelerated bone mineral resorption. Methods: We analyzed data from 4354 participants ages 40 years or older with measured ankle-brachial indexes (ABI) from the National Health and Nutrition Examination Survey from 1999 to 2002, defining PAD as an ABI &lt; 0.9 in either leg. N-telopeptides were measured in the urine. Total bone mineral content and bone mineral density were measured using dual energy X-ray absorptiometry. Results: The overall prevalence of PAD was 4.4 % (S.E, 0.3). The geometric mean of NTX was 248.3 nmol (S.E, 7.0). NTX decreased with age. Women, non-Hispanic blacks and obese individuals had significantly higher NTX levels, whereas diabetics had reduced NTX levels. Current smokers, chronic kidney disease and PAD patients tended to have higher levels as well. In an age, gender, and race adjusted multivariate analysis, one standard deviation increase in NTX level was associated with a three-fold increase in the odds of having reduced total bone mineral density (OR 3.22, p &lt;0.0001). Additionally, patients with PAD had significantly increased odds of having NTX levels in the higher tertile (O.R 1.57, p=0.035). This association persisted even after further adjustment for obesity, smoking, and C-reactive protein. Conclusion: Peripheral arterial disease is associated with reduced levels of bone mineral content and density. PAD is independently associated with N-telopeptides, suggesting abnormal type I collagen metabolism abnormalities. Further prospective studies will determine the role of NTX as a marker of osteoporosis found in PAD and their relationship with walking activity.

Impact of stocking density and feeding regimen on broilers: performance, carcass traits and bone mineralisation

To evaluate the effects of different stocking densities (22.5, 18.75, 15, 11.25, 7.5 broilers/m2) in ad libitum (Al) and limited or pair feeding (Pf) regimens a total of 2550 Ross-308 chicks were taken. All the Pf groups were provided the same amount of feed per broiler, as determined for the Al-fed group with 22.5 broilers/m2. Daily weight gain and feed intake were reduced (P≤ 0.001) as stocking density increased in the Al groups. Feed conversion ratios were worse (P≤ 0.01) in the Pf groups. Carcass yield and mortality were not affected by density or feeding method. Length (P≤ 0.001), width and bone mineral content levels (P≤ 0.05) of the tibiotarsal bone were higher in the Al groups with no effect on bone mineral density (P> 0.05). It is concluded that feed consumption was adversely affected by stocking density resulting in poor growth and bone mineralisation.

Bone Mineral Density of Children With Wilson Disease

Osteoporosis accompanying chronic liver disease is well known; however, the exact prevalence is unknown. No data on bone mineral density (BMD) of children with Wilson disease (WD) have been published so far. In this study, we aimed to investigate the prevalence of osteoporosis in childhood WD and to observe the probable positive effects of penicillamine and zinc therapy on osteoporosis. Thirty-one children with newly diagnosed WD and sex and age-matched 16 healthy children were included. Mean age was 9.0+/-3.2 years (2 to 16 y). Bone mineral content (BMC) and BMD were measured on admission and in 13 cases they were reassessed after 1 year of treatment with penicillamine and zinc. Mean BMD, BMC, and Z scores of the patients were significantly lower than those of healthy children: 0.52+/-0.09 versus 0.72+/-0.09 (P=0.001), 19.27+/-13.01 versus 29.67+/-14.23 (P=0.009), and -2.33+/-1.28 versus -0.12+/-0.31 (P=0.001), respectively. The prevalence of osteopenia and osteoporosis in children with WD was found as 22.6% and 67.7%, respectively. BMD and BMC levels were higher in children with neurologic involvement. The severity of the disease had no effect on the mentioned parameters. One year under treatment with penicillamine and zinc did not significantly alter the mentioned parameters. In this first study investigating the prevalence of osteoporosis in children with WD, we found an extremely high prevalence. Because of nonbeneficial effect of routine treatment of WD on osteoporosis, we emphasize the necessity of screening of bone mineralization and additional therapeutic approach for those children.

Location of body fat and body size impacts DXA soft tissue measures: a simulation study

The aim of this study was to determine the ability of dual X-ray absorptiometry (DXA) to detect exogenous fat in men and women simulating typical sex-specific weight changes. A diverse sample including 29 elderly (52-83 years) and 61 young (18-40 years) individuals (45 women, 45 men) of varying body mass index (BMI; M+/-s.d.: 26.1+/-4.9 kg/m2, range=16.4-39 kg/m2). Whole body (WB) DXA scans (Hologic QDR 4500A) were completed with Scan 1 performed as a normal baseline scan, Scan 2 with 1 kg packet of lard placed on each thigh and Scan 3 with two 1 kg lard packets placed on the abdomen (men) or chest and abdomen (women). Measurement error of fat mass (FM) was more pronounced in the trunk as lard packets were detected with 59% accuracy (error=0.82+/-0.42 kg, P<0.001), whereas 94% of thigh lard (error=0.11+/-0.45 kg, P<0.001) was determined to be FM, while the remainder in both conditions was determined to be mineral free lean mass. Initial FM (r=0.37, P<0.001) for thigh loading and trunk bone mineral content (r=0.30, P<0.01) for trunk-loaded conditions had the most impact on measurement error of WB FM. Regional differences impact measurement error of simulated changes in FM with greater measurement error in the trunk compared to the thigh region and initial FM and higher levels of bone mineral content in the trunk region impacting error.

KOSTNYY METABOLIZM I POTERYa KOSTNOY TKANI V OTDALENNYE SROKI POSLE ALLOTRANSPLANTATsII TRUPNOY POChKI (ATP) (ODNOMOMENTNOE ISSLEDOVANIE)

Bone turnover markers [osteocalcin (OC), carboxyterminal procollagen I propeptide (PICP), bone alkaline phosphatase (bALP), deoxypyridinoline (DPD), β -crosslaps (CTX), bone acid phosphatase (bACP), parathyroid hormone (PTH)], day calcium excretion (uCaV) and lumbar and hip bone mineral content (BMC) were determined in 195 patients [78 women and 74 men with intact renal function as well as 11 women and 31 men with renal failure (RF)] 40±33 months following KT. KT recipients received triple immunosuppressive therapy (CysA, prednisolone and azathioprine). All groups showed bone remodeling dissociation namely bone resorption increase (high CTX, DPD, bACP) and bone formation retard (mild enhanced level OC, normal or low bALP) in association with high PTH, decreased uCaV and BMC levels. High bone turnover and low uCaV were much more high degree in RF. Vertebral and femur BMC decrease was mild (osteopenia) and only men with RF revealed peripheral osteoporosis. Hyperparathyroidism was associated with decreased transplant function and was main predictor of high bone turnover and bone loss after KT.

Standardized data and relationship between bone growth and bone metabolism in female Göttingen minipigs.

Minipigs have been studied as a model of osteoporosis. However, little information is available regarding their bone physiology. We established standardized bone data and investigated the relationship between bone growth and bone metabolism in female minipigs. Blood and urine samples were obtained from 53 female Göttingen minipigs, 3-76 months of age, for measurement of bone biomarkers (i.e., BAP, OC, NTX, and DPD). The lumbar vertebra and femur were excised to determine the growth plate condition, bone length, bone mineral content (BMC), and bone mineral density (BMD). High levels of bone biomarkers were observed during the initial period after birth, decreasing thereafter with age. Bone biomarkers were confirmed to be highly correlated with age (R(2) > 0.7). The growth plates of the lumbar vertebra and the femur began to close at 21 and 25 months of age, respectively, and closed completely at 42 months of age. Bone length increased rapidly before growth plate closure, and reached a peak at 21 and 28 months of age in the lumbar vertebra and the femur, respectively. The levels of BMC and BMD increased rapidly before growth plate closure, and continued to increase slowly until 76 months of age. A high negative correlation (-0.855 < r < -0.711, p<0.001) was confirmed between the bone biomarkers and the bone measurement data. These results indicate that the bone turnover velocity is consistent with the bone growth velocity in female Göttingen minipigs.

Increments in Whole Body Bone Mineral Content Associated With Weight and Length in Pre-Term and Full-Term Infants During the First 6 Months of Life

Background The objective of the present study was to assess bone mineral content (BMC) of the whole skeleton in pre-term and full-term healthy infants and the factors influencing BMC, such as bone area, birth weight, birth length, current weight, current length, gender, and gestational age. Methods Forty-eight healthy full-term infants and 34 healthy premature infants fed predominantly with intact human milk were studied. BMC was measured monthly with dual energy X-ray absorptiometry (DEXA). At the same time, length and weight were measured and registered. Pre-term infants were studied at 60-day intervals. Results For both full-term and pre-term infants, BMC increased during the first months of life. However, the values of pre-term infants never reached the values of full-term infants, even after correcting for age and weight. For both full-term and pre-term infants, BMC was significantly correlated at the second month with birth weight ( r = 0.901), birth length ( r = 0.860), gestational age ( r = 0.803), bone area ( r = 0.960), current weight ( r = 0.920), and current length ( r = 0.840, p <0.001 for all correlation coefficients). Multivariate analysis revealed that bone area was the most important factor in predicting BMC. Conclusions Pre-term children have lower BMC than full-term children. The main factor explaining this apparent osteopenia is bone area. Pre-term children have a higher daily mineralization rate than full-term children, but this catch-up mineralization is not enough to reach BMC levels seen in full-term children.

The effects of sex steroids and some elements of lifestyle on the normal variation of bone mineral content in younger versus older healthy Polish males

The aim of the study was to evaluate the independent ‘net’ effects of hormonal variables (estradiol, free testosterone and dehydroepiandrosterone sulfate (DHEAS) levels) and lifestyle variables (alcohol consumption, coffee drinking, cigarette smoking, physical activity and muscle strength) on trabecular, cortical and total bone mineral content (BMC) in a group of 236 healthy males, aged 22–67 years. The men were occupationally active inhabitants of the city of Wroclaw, Lower Silesia, Poland. Trabecular, cortical and total bone mineral content, at the distal radius of the non-dominant hand, were assessed by peripheral quantitative computed tomography (pQCT) using the Stratec 960 apparatus. Sex steroids levels were measured using standard immunoassays. Data on lifestyle variables (alcohol consumption, cigarette smoking, coffee drinking and physical activity) were obtained through a questionnaire. Hand-grip strength of the dominant hand was assessed using a standard dynamometer. All statistical analyses were made separately in two subgroups, younger males (aged 22–39 years) and older males (aged 40 years and over). The impact of a particular independent variable on BMC and the extent of determination on BMC by the complex of chosen variables were evaluated using a path analysis. In younger males, the effects of physical activity and muscle strength were the most important among all the factors that influenced BMC, as they contributed to 16.2%, 16.9% and 16.5% of the variability of trabecular, cortical and total BMC, respectively. Taking into consideration cigarette smoking, alcohol and coffee drinking together, the coefficients of determination of the variability in trabecular, cortical and total BMC were 10.6%, 11.3% and 16.1%, respectively. The variances in trabecular, cortical and total BMC levels were determined in only 5.8%, 11.5% and 13.0% by sex steroids, respectively. The influence of free testosterone on trabecular BMC was greater compared with that of dehydroepiandrosterone sulfate (DHEAS) and estradiol; for cortical BMC, the impacts of estradiol and DHEAS were similar and greater than that of free testosterone, and the variability of total BMC was affected mainly by estradiol. In contrast, in older men the effects of physical activity and muscular strength were the least important among all the complexes of independent variables, as they contributed to 4.5%, 7.8% and 7.0% of the variability in trabecular, cortical and total BMC, respectively. Taking into consideration the influences of cigarette smoking, alcohol and coffee drinking, the coefficients of determination of the variability in trabecular, cortical and total BMC were 16.5%, 14.8% and 17.4%, respectively. Among the older men, the variances in trabecular, cortical and total BMC were determined in only 9.4%, 6.3% and 13.6% by sex steroid levels, respectively. The influence of DHEAS on trabecular BMC was greater when compared with that of estradiol and free testosterone, whereas the variability of both cortical and total BMC in older men was affected mainly by estradiol. It is quite striking that, in younger healthy subjects, both physical activity and muscle strength contributed to a greater extent to BMC variance when compared with sex steroids levels, whereas, in older men, physical activity and muscular strength were less important than androgen- estrogen activity in determining the variability of BMC. This may suggest that the tropic effect of mechanical force influences bone structure mainly in younger men; probably male bone tissue becomes less prone to mechanical stimuli during aging. It is astonishing that both in younger and older men the coefficients of determination of physical activity and muscle strength were the highest for cortical BMC, which would indicate the greatest response of that part of the bone tissue to mechanical force. It is worth noting that the coefficients of determination of the complex of lifestyle factors (alcohol consumption, cigarette smoking and coffee drinking) were higher in older men compared to younger Polish males. This can be explained by the longer exposure of male bone to environmental influences (ethanol, nicotine, caffeine) during a lifetime. Our study revealed that all the evaluated variables were related to the variability in BMC in healthy Polish men, but the coefficients of determination differed depending on the age of the examined subject and on the BMC of a particular bone component. This suggests that the responsiveness of male bone tissue to environmental factors changes with age, and that these effects vary significantly between particular parts of the male bone structure.

Bone mineral content in medieval Greenland Norse

The bone mineral content (BMC) was measured using a special dual-photon scanner in 25 mandibles with normal macroscopic and radiographic bone structure. The mandibles were excavated from two Norse sites in Greenland, which date to the first and last part of the medieval Norse settlement period, respectively. The main purpose of this study was to investigate whether there was a change in BMC levels between the early and the late settlement period. The results showed no difference in male BMC between the early and the late site material. A statistically significant gender difference was found, analogous to most clinical and archaeological BMC studies. The sample did not allow testing for age-related, especially female postmenopausal-related, bone loss. It is known that Eskimos generally have a very low BMC, probably the effect of a high-protein marine diet. The lack of decrease in BMC levels for the Norse could indicate that they did not increase their overall protein intake over the 500-year settlement period. Other studies (both archaeological and anthropological) point to an increased reliance on marine foodstuffs throughout the settlement period. Thus, if the Norse increased their reliance on marine foodstuffs, they probably did not do so to the extent of an almost exclusive marine diet like that of the Eskimo. © 1997 John Wiley & Sons, Ltd.

Bone mineral content in medieval Greenland Norse

The bone mineral content (BMC) was measured using a special dual-photon scanner in 25 mandibles with normal macroscopic and radiographic bone structure. The mandibles were excavated from two Norse sites in Greenland, which date to the first and last part of the medieval Norse settlement period, respectively. The main purpose of this study was to investigate whether there was a change in BMC levels between the early and the late settlement period. The results showed no difference in male BMC between the early and the late site material. A statistically significant gender difference was found, analogous to most clinical and archaeological BMC studies. The sample did not allow testing for age-related, especially female postmenopausal-related, bone loss. It is known that Eskimos generally have a very low BMC, probably the effect of a high-protein marine diet. The lack of decrease in BMC levels for the Norse could indicate that they did not increase their overall protein intake over the 500-year settlement period. Other studies (both archaeological and anthropological) point to an increased reliance on marine foodstuffs throughout the settlement period. Thus, if the Norse increased their reliance on marine foodstuffs, they probably did not do so to the extent of an almost exclusive marine diet like that of the Eskimo. © 1997 John Wiley & Sons, Ltd.

BODY COMPOSITION OF LARGE-FOR-GESTATIONAL AGE INFANTS. 1266

There are no reports on direct measurements of body composition in macrosomic infants. We hypothesize that large-for-gestational age (LGA) infants will have higher total body fat (TBF), lean body mass (LBM) and bone mineral content (BMC) as assessed by dual energy x-ray absorptiometry (DXA) when compared to appropriate birth weight for gestational age (AGA) infants. Thirty-seven LGA term infants (24B, 13W; 22M, 15F) with birth weights from 4000 g to 5040 g were compared with 37 gestational age-matched AGA infants(20B, 17W; 21M, 16F) with birth weights from 2700g to 3990g. Ten of the LGA infants were born to mothers with gestational (8) and class B (1) and C (1) diabetes. DXA scans were performed at 1.8±0.97 days after birth using Hologic QDR 1000/W densitometer with a pediatric platform. Scan analyses were performed with software version V5.64P. LGA infants had significantly(p<0.001) higher total amounts of mean (±SD) TBF (1008±288g vs 524±145g), LBM (3414±208g vs 2740±197g) and BMC(99.2±11.23g vs 66.6±8.95g). However, as a percent of body weight, LGA infants had significantly higher TBF (22±5.09% vs 15.6±3.37%) and lower LBM (75.8±5.12% vs 82.4±3.47%)(p<0.001, respectively) but similar levels of BMC when compared to AGA infants. Infants of diabetic mothers had similar but exaggerated changes in body composition, i.e., greater TBF and relatively lower LBM. We conclude that LGA infants have significantly different body composition from that of AGA infants, specifically there is disproportionately higher body fat and lower lean body mass, but there is proportionate increase in bone mineral content. These findings on changes of body composition in macrosomic infants may provide insight into the effect of in utero environment on fetal growth and improve postnatal management of such infants.

Bone Mineral Content in Infants and Children With Chronic Cholestatic Liver Disease

To assess bone mineral content (BMC) status and serum vitamin D metabolite levels of infants and children with chronic cholestatic liver disease. To determine if severity of bone disease in these patients correlates with serum vitamin D metabolite levels. We measured radial BMC with the use of a single-beam photon absorptiometer and serum vitamin D metabolite levels in 56 patients with chronic cholestasis seen at our institution from 1985 through 1991. Patients were divided into two groups according to age. In group 1 (n = 37; age 2 to 22 months), decreased levels of BMC were seen as early as the first few months of life, with sharp decline observed with increasing age (approaching 3 to 5 standard deviations [SD] below the mean, P < .0003). Older patients (group 2, n = 19; age 2 to 20 years) had BMC values which clustered between 2 and 4 SD below the mean throughout the age range. Although a downward trend also was noted with increasing age, this was not statistically significant. Despite correction for weight-age or height-age, BMC was decreased in most of these patients. No correlation between severity of osteopenia and serum levels of 25(OH)-vitamin D and 1,25(OH)2-vitamin D was observed in either infants or older children. Decreased bone mineralization, as a complication of chronic cholestatic conditions, is a disease process that begins early in infancy, rapidly worsens with increasing age and hepatic dysfunction, and remains relatively stable in children with more stable liver disease.

Determinants of bone mineral content in childhood

In a sample of 1190 children (574 boys and 616 girls), aged 6.8–10.7 years, bone mineral content was studied using quantitative röntgen microdensitometry (QMD) at the diaphyseal and the metaphyseal site of the left second digit. Percentile curves of bone mineral density was determined by skeletal age for boys and girls separately. Bone mineral content at the diaphyseal site was significantly associated with skeletal age, height and body weight in boys and girls and with chronological age at the metaphyseal site in boys. In girls higher levels of bone mineral content were observed in those with a skeletal age greater than 7.3 years, compared to those with a skeletal age equal or less than 7.3 years, adjusted for height and body weight. In boys a higher level of bone mineral content was found in those with a height greater than 138 cm, adjusted for skeletal age, compared to those with a height equal or less than 130 cm, at the diaphyseal and metaphyseal site. Girls with a relatively higher body weight had lower levels of bone mineral content at the metaphyseal site.

Differential effects of thiazide and estrogen upon bone mineral content and fracture prevalence

Individual and combined effects of thiazides and estrogens upon bone mineral content at four sites (proximal radius, distal radius, os calcis, lumbar spine) and fracture prevalence were assessed retrospectively in 993 postmenopausal women. Compared with untreated women, use of thiazide alone was associated with significantly higher bone mineral content (P less than or equal to .01); nonspine fracture prevalence in this group was reduced by one-half (P = .07). Estrogen alone also was associated with significantly higher bone mineral content (P less than or equal to .0001); nonspine fracture prevalence was reduced by almost one-half (P = .07). The users of both estrogen and thiazide had the highest bone mineral content levels, which were significantly different than the thiazide-only group at four bone sites (P less than or equal to .001), and the estrogen-only group for three bone sites (P less than or equal to .05). Nonspine fracture prevalence for the users of both drugs was 17% that of the untreated group (P = .02). The relationships with spine fracture prevalence were less consistent; however, estrogen users appeared to have a lower spine fracture prevalence rate and higher spinal bone mineral content than thiazide users. These findings suggest a potential role for thiazides in the prevention of osteoporosis.

Bone disorder following partial and total gastrectomy with reference to bone mineral content.

To study post-gastrectomy metabolic bone disorders, we measured the radial bone mineral content (BMC), serum levels of calcium, inorganic phosphorus, alkaline phosphatase, and 25-hydroxyvitamin D(25-OH-D) in 59 patients with partial- and 39 patients with total gastrectomy. Total gastrectomy patients manifested a higher incidence of decreased BMC levels than did partial gastrectomy patients (56 per cent vs. 25 per cent). Patients subjected to the Billroth II procedure, especially females, manifested abnormally low BMC values. The decline in BMC was age-related; it was pronounced in females. At 10 years postoperatively, many of the partial gastrectomy patients manifested markedly low BMC levels; in totally gastrectomized patients this finding was made at less than 5 years postoperatively. Approximately 30 per cent of our patients showed abnormalities in serum minerals, alkaline phosphatase or 25-OH-D.

Use of bone mineral content determination in the evaluation of osteodystrophy among hemodialysis patients.

During a period of 2 years, bone mineral content (BMC) was measured regularly in patients undergoing regular dialysis treatment (RDT). Low BMC values were found to be correlated to long duration of uremia, raised alkaline phosphatase activity, hyperaluminemia, hypermagnesemia, hypophosphatemia and clinical osteodystrophy. High levels of BMC loss were found among patients with relatively high initial BMC levels and severely calciopenic patients actually gained bone density during the investigation. Serum alkaline phosphatase activity and serum immunoreactive parathyroid hormone (PTH) levels were positively related to bone loss. It is suggested that the low BMC among RDT patients is caused by a predialytic loss that is arrested by entrance into a dialysis programme. Investigations using BMC or total body calcium as a measure of therapeutic effect must take account of this. The role of hypermagnesemia and hyperaluminemia remains undefined. Patients with BMC reduced below ca. 80% of normal may be candidates for treatment with active vitamin D metabolites.