Osteoporosis in men

Association of Sarcopenia with Osteopenia and Osteoporosis in Community-Dwelling Older Korean Adults: A Cross-Sectional Study

Sarcopenia and bone disorders, such as osteopenia and osteoporosis, are common musculoskeletal disorders in older adults. Therefore, this study aimed to establish the association between sarcopenia and bone disorders such as osteoporosis and osteopenia according to sex. We analyzed 3077 participants from the 2008-2011 Korean National Health and Nutrition Examination Survey aged 65 years or older. After adjusting for all covariates, such as physical examinations, exercise, and nutrient intake (model 4), the odds ratios for the association between sarcopenia and bone disorders were 2.051 (95% confidence interval [CI]: 1.498-2.808) in osteopenia and 2.258 (95% CI: 1.584-3.218) in osteoporosis. However, when sex was analyzed separately, the odds ratio was significantly different in men (osteopenia-2.068, 95% CI: 1.462-2.924; osteoporosis-3.247, 95% CI: 1.953-5.399), but not in women. Therefore, the results of this study show an association between sarcopenia and bone disorders in older Korean adults. Sarcopenia is significantly related to osteopenia and osteoporosis, especially in men, when stratified by sex.

Associations between sleep duration, daytime nap duration, and osteoporosis vary by sex, menopause, and sleep quality

CONTEXT

Associations between sleep, daytime nap duration, and osteoporosis remain uncertain, and far less is even known about the influence of sex, menopause, and sleep quality on them.

OBJECTIVE

The objective of the study was to test the associations between sleep, daytime nap duration, and osteoporosis and whether they vary by sex, menopause, and sleep quality.

DESIGN, SETTING, AND PATIENTS

This cross-sectional study was based on two communities in China. A total of 8688 participants (3950 males and 4738 females) aged 40 years or older were enrolled in the study.

MAIN OUTCOMES MEASURES

Self-reported sleep duration, daytime nap duration, sleep quality, and calcaneus bone mineral density were recorded.

RESULTS

Sleep duration of 8-9 h/d and nap duration of 0 min/d were regarded as reference values. In postmenopausal women, risks (odds ratio and 95% confidence interval) of osteoporosis for sleep durations of 7-8 h/d, 9-10 h/d, and 10 h/d or longer were 1.531 (1.106, 2.121), 1.360 (1.035, 1.787), and 1.569 (1.146, 2.149), respectively (P < .05), and risks of osteoporosis for daytime nap durations of 30-60 min/d and longer than 60 min/d were 1.553 (1.212-1.989) and 1.645 (1.250-2.165), respectively (P < .05). However, a significant difference was not consistently observed in men or premenopausal women, regardless of sleep or daytime nap duration. As for sleep quality, positive results were seen most remarkably in postmenopausal females with good sleep.

CONCLUSIONS

Sleep durations of 7-8 h/d, 9-10 h/d, and 10 h/d or longer, as well as longer daytime napping times, tend to present higher risks of having osteoporosis, and this tendency is most obvious in postmenopausal women reporting good-quality sleep.

The pathogenesis, treatment and prevention of osteoporosis in men

Testosterone stimulates longitudinal and appositional growth during childhood, whereas estrogen induces epiphysial closure. During adulthood, testosterone continues to stimulate periosteal growth, whereas estrogen is important for the maintenance of trabecular bone mass and structure. In males, testosterone is aromatized to estradiol. Both free and bioavailable plasma levels of testosterone and estradiol decrease with age in males, and fracture risk is associated with low estradiol levels. Testosterone may increase muscle mass and prevent fractures related to falls. Younger hypogonadal males should be treated with testosterone to attain peak bone mass and increase bone mineral density (BMD). Older hypogonadal males should be treated in cases of osteoporosis, reduced muscle strength and increased risk of falling. Secondary hyperparathyroidism caused by calcium and vitamin D insufficiency may reduce bone mass and strength and increase fracture risk and should be avoided. Since calcium supplementation has been associated with an increased risk of cardiovascular complications and renal stones, the dose should be tailored to the habitual daily calcium intake. Lifestyle-related risk factors (smoking, alcohol consumption, lack of physical activity and low body weight) should be addressed. The antifracture efficacy of antiresorptive and anabolic treatment for osteoporosis has not been documented in larger randomized controlled studies. However, changes in BMD and bone markers suggest similar effects in males and females of bisphosphonates (alendronate, risedronate, ibandronate, zoledronic acid), nasal calcitonin, denosumab and teriparatide (parathyroid hormone [1-34]). The antiresorptive drugs should be used in males with BMD T-score less than -2.5 and one or more risk factors, or with hip and vertebral fractures. It seems appropriate to recommend a higher cut-off T-score (e.g. less than -1.0 standard deviation [SD]) in glucocorticoid-induced osteoporosis and in patients receiving androgen deprivation therapy because of the fast initial bone loss. Anabolic treatment should be used in more severe spinal fracture cases, including glucocorticoid-induced osteoporosis.

Ethnic and sex differences in bone marrow adipose tissue and bone mineral density relationship

The relationship between bone marrow adipose tissue and bone mineral density is different between African Americans and Caucasians as well as between men and women. This suggests that the mechanisms that regulate the differentiation and proliferation of bone marrow stromal cells may differ in these populations.

INTRODUCTION

It has long been established that there are ethnic and sex differences in bone mineral density (BMD) and fracture risk. Recent studies suggest that bone marrow adipose tissue (BMAT) may play a role in the pathogenesis of osteoporosis. It is unknown whether ethnic and sex differences exist in the relationship between BMAT and BMD.

METHODS

Pelvic BMAT was evaluated in 455 healthy African American and Caucasian men and women (age 18-88 years) using whole-body T1-weighted magnetic resonance imaging. BMD was measured using whole-body dual-energy X-ray absorptiometry.

RESULTS

A negative correlation was observed between pelvic BMAT and total body BMD or pelvic BMD (r = -0.533, -0.576, respectively; P < 0.001). In multiple regression analyses with BMD as the dependent variable, ethnicity significantly entered the regression models as either an individual term or an interaction with BMAT. Menopausal status significantly entered the regression model with total body BMD as the dependent variable. African Americans had higher total body BMD than Caucasians for the same amount of BMAT, and the ethnic difference for pelvic BMD was greater in those participants with a higher BMAT. Men and premenopausal women had higher total body BMD levels than postmenopausal women for the same amount of BMAT.

CONCLUSIONS

An inverse relationship exists between BMAT and BMD in African American and Caucasian men and women. The observed ethnic and sex differences between BMAT and BMD in the present study suggest the possibility that the mechanisms regulating the differentiation and proliferation of bone marrow stromal cells may differ in these populations.

Diseases affecting bone quality: beyond osteoporosis

BACKGROUND

Bone quantity, quality, and turnover contribute to whole bone strength. Although bone mineral density, or bone quantity, is associated with increased fracture risk, less is known about bone quality. Various conditions, including disorders of mineral homeostasis, disorders in bone remodeling, collagen disorders, and drugs, affect bone quality.

QUESTIONS/PURPOSES

The objectives of this review are to (1) identify the conditions and diseases that could adversely affect bone quality besides osteoporosis, and (2) evaluate how these conditions influence bone quality.

METHODS

We searched PubMed using the keywords "causes" combined with "secondary osteoporosis" or "fragility fracture." After identifying 20 disorders/conditions, we subsequently searched each condition to evaluate its effect on bone quality.

RESULTS

Many disorders or conditions have an effect on bone metabolism, leading to fragility fractures. These disorders include abnormalities that disrupt mineral homeostasis, lead to an alteration of the mineralization process, and ultimately reduce bone strength. The balance between bone formation and resorption is also essential to prevent microdamage accumulation and maintain proper material and structural integrity of the bone. As a result, diseases that alter the bone turnover process lead to a reduction of bone strength. Because Type I collagen is the most abundant protein found in bone, defects in Type I collagen can result in alterations of material property, ultimately leading to fragility fractures. Additionally, some medications can adversely affect bone.

CONCLUSIONS

Recognizing these conditions and diseases and understanding their etiology and pathogenesis is crucial for patient care and maintaining overall bone health.

Men's experiences of living with osteoporosis: focus group interviews

Osteoporotic fractures in men are an increasing public health problem. Male osteoporosis is often a low-prioritized issue, however. To examine men's experiences with osteoporosis and how they handle osteoporosis in their everyday lives, the authors collected data from four focus groups with a total of 16 men aged 51 to 82 years diagnosed with osteoporosis. Critical psychology was used as a theoretical framework for the data analysis, which aimed to elicit information about the men's daily lives. The men handled osteoporosis in different ways using different strategies. The authors found patterns that resonated with the social construction of hegemonic masculinity as displayed through the men's fear of weakness and endurance through physical activity, as well as identity construction through active decision making in relation to health. Understanding and implementation of these issues is necessary in the development of preventive, screening, and monitoring strategies, as well as in the clinical care of men with osteoporosis.

Lack of biochemical hypogonadism in elderly Arab males with low bone mineral density disease

The aim of the study is to study the relationship between androgen levels and bone mineral density (BMD) in elderly Arab males. Forty-five elderly Arab males underwent Dual X-ray absorptiometry for measurement of BMD. The outcomes were defined as per WHO description. Assays for testosterone (T), gonadotropins (LH and FSH) and estradiol (E2), in the serum were carried out. The ratio of T/LH was used as a surrogate for the cFT assay. We excluded patients receiving hormonal ablation for prostatic neoplasm and patients with chronic liver or renal disease and patients receiving corticosteroids. Twelve were osteoporotic (26.5%); 22 osteopenic (49%); and 11(24.5%) had normal outcome. Osteoporotic patients were significantly older (78.17 +/- 7.59 years) than the osteopenic (70.14 +/- 5.92, P <or= 0.01 and the normal subjects (71.20 +/- 4.17, P <or= 0.05). The means of total serum T, LH, FSH and E2 were all within the normal values and not significantly different between the three groups. Like wise were the means of the ratios of T/LH and E2/T too. A significant number of subjects in this cohort of elderly Arab males had reduced bone density that appears to be independent of androgen levels. Osteoporotics were significantly older than those with osteopenia or normal bone density. Aging seemed to have overridden the effect of normal sex hormones on bone density in these patients. Before considering these results as a possible exception to the widely established role of the hypoandrogenemia in male osteoporosis, other potential factors impacting on bone density need to be considered.

The relationship between periodontal status and alkaline phosphatase levels in gingival crevicular fluid in men with hypergonadotropic hypogonadism

PURPOSE

The aim of this preliminary study was to determine the possible relationship between alkaline phosphatase (ALP) levels in the gingival crevicular fluid (GCF) and periodontal disease in men with hypergonadotropic hypogonadism (HH).

MATERIALS AND METHODS

A total of 41 patients were divided into four groups. 9 with HH and periodontitis (P/HH), 11 with HH and gingivitis (G/HH), 12 with systemically healthy and periodontally healthy (H/C) and 9 with systemically healthy and periodontitis (P/C). The clinical evaluation of patients was based on the following parameters; the plaque index (PI), gingival index (GI), probing depths (PD) and attachment level (AL). The levels of ALP in the GCF were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

No significant difference could be detected in the mean clinical parameter data between the P/HH and P/C groups (p > 0.05). The periodontitis patients in both groups (P/C and P/HH) had higher mean probing depths than the H/C and G/HH patients (p < 0.001). The concentrations and total amounts of ALP in the GCF were significantly higher in both periodontitis groups compared to healthy and gingivitis groups (p < 0.01). The serum ALP levels were significantly higher in the P/HH group when compared to the other groups (p < 0.001).

CONCLUSION

The findings of this study suggested that HH could be implicated as a contributing factor to the progress of periodontal disease.

Osteoporosis in men and women

Osteoporosis is a cause of significant morbidity and mortality in postmenopausal women as well as men. In both men and women, increasing age and low bone mineral density (BMD) are the 2 most important independent risk factors for an initial vertebral or nonvertebral fracture. Although the prevalence of osteoporosis is greater in women, mortality after fracture is higher among men. In both men and women, the incidence of vertebral fracture increases with age, although the increase is more marked in women than in men. The diagnostic criteria for postmenopausal osteoporosis in women are well established; however, there is ongoing debate about the appropriate T-scores and BMD thresholds to diagnose osteoporosis in men. Alendronate and risedronate are considered first-line therapy for the treatment of both postmenopausal osteoporosis and male osteoporosis. The efficacy and safety of these agents have been evaluated extensively in randomized clinical trials. Studies suggest that these agents are similarly efficacious in men and women. The anabolic agent teriparatide may also be used to treat men with osteoporosis at high risk for fracture. Studies suggest that treatment with an anabolic agent like teriparatide should be followed by an antiresorptive agent.

Low transforming growth factor-beta1 serum levels in idiopathic male osteoporosis

INTRODUCTION

Although the etiology of osteoporosis is different between men and women, the underlying pathophysiological mechanism is similar, namely an absolute or relative increase in bone resorption, leading to progressive bone loss. Transforming growth factor (TGF)-beta1 is a growth factor in human bone, which is produced by osteoblasts, and which has various effects on osteoclasts and osteoblasts. The aim of our study was to determine serum TGF-beta1 levels in male patients with idiopathic osteoporosis.

METHODS

Twenty five males with idiopathic osteoporosis and 25 age-matched controls were studied. Osteoporosis was defined by a T score of <-2.5 in the lumbar spine or at the femoral neck. We measured levels of TGF-beta1, estradiol, total and bioactive testosterone. Various markers of bone remodeling were also measured.

RESULTS

TGF-beta1 was significantly lower in osteoporotic patients than in controls (3.706 ng/dl, 25-75 percentiles: 2.81-5.33 vs 8.659 ng/dl, 25-75 percentiles: 4.837-11.835; p=0.000). Moreover, TGF-beta1 levels were positively correlated with bone mineral density (BMD) at the femoral neck (r=0.439, p=0.028), and at the lumbar spine (r=0.41, p=0.042). No correlation was found between serum estradiol, testosterone and TGF-beta1 levels.

DISCUSSION

Serum TGF-beta1 levels are depressed in osteoporotic men and are positively correlated with hip and spine BMD. The results of our study suggest that TGF-beta1 may play a role in the pathogenesis of idiopathic male osteoporosis.

Prevalence of low forearm bone mineral density in Bulgarian men: a pilot study

OBJECTIVE

To determine the prevalence of osteoporosis at the distal forearm in a male cohort referred for bone density testing and to compare it to published data of Bulgarian women.

DESIGN AND SUBJECTS

315 consecutive Bulgarian men aged 20 to 84 years were included (mean age 53.74 +/- 14.67 years). 59% of them were self-referrals. The comparative female group consisted of 8869 Bulgarian women whose forearm bone mineral density (BMD) was measured in another study.

MEASUREMENTS

BMD was measured by single X-ray absorptiometry at the distal forearm (distal and ultradistal sites) in all men. T-scores were calculated from manufacturer-provided Danish male reference data.

RESULTS

The ratio of female to male patients was 28.2 (8869 to 315). Peak BMD was observed in men aged 30 to 39 years: 0.560 +/- 0.065 g/cm(2) (distal site) and 0.490 +/- 0.070 g/cm(2) (ultradistal site). A steady BMD decline followed reaching 0.492 +/- 0.064 g/cm(2) at the distal and 0.412 +/- 0.069 g/cm(2) at the ultradistal site in age group >70. Age had a rather weak negative impact on forearm BMD described by a linear model. In men aged over 50 years the prevalence of osteoporosis at the distal site was 21.19%, compared to 20.45% in women. Low bone mass was seen in 48.77% of men and 32.50% of women. Normal BMD was more frequent in women (47.05%) than in men (30.04%).

CONCLUSIONS

We found a high prevalence of forearm osteoporosis in Bulgarian men which is comparable to that already known in women.

Utility of biochemical screening in the context of evaluating patients with a presumptive diagnosis of osteoporosis

The ageing population is expected to increase the burden of osteoporosis on the health care system. Secondary causes of osteoporosis are found in a proportion of patients. There is much controversy regarding the best work-up for patients who have been diagnosed as having osteoporosis based on bone mineral density. It is difficult to decide where interventions should be targeted both from a patient's perspective and for cost effectiveness. We evaluated the utility of a standard panel (full blood count, plasma viscosity, plasma protein, electrophoresis, urine Bence Jones protein, thyroid function test, bone profile, fasting lipids and liver function test) of biochemical investigations in 327 consecutive patients (287 females, 40 males) referred to the new patient osteoporosis clinic from April 1999 to March 2000. Patients were characterised after measurement of spinal/femoral neck bone mineral density after a dual energy X-ray absorptiometry (DEXA) scan. There were 88 patients with osteoporosis, 91 with osteopenia, 130 had normal bone mineral density and 20 who did not have a bone scan. No case of multiple myeloma was found in this cohort of patients. There was no difference in the mean plasma viscosity of patients with and without osteoporosis (P=0.182). There was no significant difference in the abnormal urine calcium/creatinine (Ca/Cr ratio) in patients with osteoporosis and those without osteoporosis (P=0.316). There was no significant difference in the prevalence of hypothyroidism (P=0.213) or thyrotoxicosis (P=0.138) in patients with and without osteoporosis. There was no strong correlation between cholesterol concentrations and osteoporosis (r=0.069). We found no utility in performing a myeloma screen. A small proportion of patients had abnormalities of calcium homeostasis or thyroid disease. We recommend that a screening biochemical evaluation should be restricted to calcium/bone profile and thyroid function tests in patients with a presumptive diagnosis of osteoporosis.

Weekly Oral Alendronic Acid in Male Osteoporosis

OBJECTIVE

To evaluate the efficacy and tolerability of alendronic acid 70mg once weekly for the treatment of male osteoporosis.

PATIENTS AND METHODS

This randomised, double-blind, placebo-controlled, 12-month trial compared the effect of alendronic acid 70mg once weekly or placebo (randomised 2 : 1) on bone mineral density (BMD) in 167 men with spine or hip BMD at least 2 standard deviations (SD) below the mean for young normal white males or nontraumatic fracture. All patients received calcium and vitamin D (colecalciferol). We measured lumbar spine, hip and total body BMD, and biochemical markers of bone turnover. Fractures were collected as adverse events.

RESULTS

Alendronic acid 70mg once weekly produced significant BMD increases from baseline of 4.3% at the spine, 2.1% at the femoral neck, 2.4% at the trochanter, and 1.4% at the total body, which were all significantly greater than placebo (p < 0.05). The increase at the lumbar spine was significant relative to baseline and placebo after 6 months of treatment (p < 0.001). The treatment effect was consistent regardless of BMD, age, height, weight, body mass index (BMI) and hypogonadal status at baseline. Alendronic acid significantly decreased biochemical markers of bone turnover relative to baseline and placebo. Alendronic acid was generally well tolerated, with an incidence of gastrointestinal adverse events similar to placebo.

CONCLUSION

Alendronic acid 70mg administered once weekly is an effective and convenient alternative to daily dosing for the treatment of male osteoporosis.

Clinical characteristics and etiologic factors of premenopausal osteoporosis in a group of Spanish women

OBJECTIVES

To analyze the clinical characteristics and the principal causes of osteoporosis in premenopausal women.

METHODS

This study included 52 osteoporotic premenopausal women ages 20-51 years (mean 36.2 +/- 7) who were referred to an outpatient rheumatology department for osteoporosis evaluation. Bone mass assessment, automated biochemical profile, urinary calcium excretion, and bone marker assays were performed on all patients. Hormonal measurements were made when a specific etiology was not readily apparent. The diagnosis of osteoporosis was defined by the presence of atraumatic vertebral fractures and/or by densitometric criteria. Previous skeletal fractures, weight, height, body mass index (BMI), age at menarche, and family history of osteoporosis also were recorded.

RESULTS

Twenty-nine patients (56%) had idiopathic osteoporosis and 23 (44%) had secondary osteoporosis. Fifteen patients (29%) had vertebral fractures and 12 had previous peripheral fractures. Patients with secondary osteoporosis showed higher BMI (23.2 +/- 3 v 21.2 +/- 2, P =.02) and lower femoral Z-scores of bone mineral density (BMD) (-2.1 +/- 0.6 v -1.5 +/- 0.9, P =.02) than those with idiopathic disease. The most frequent causes of secondary osteoporosis included Cushing syndrome, pregnancy osteoporosis, and osteogenesis imperfecta. Nearly half of the patients (48%) with idiopathic osteoporosis had a family history of osteoporosis. In addition, 11 patients (38%) with idiopathic osteoporosis had associated hypercalciuria. Except for an increase in urinary calcium excretion (248 +/- 53 v 143 +/- 47 mg/24 h, P <.0001), no other significant differences in the remaining variables analyzed were found between hypercalciuric and normocalciuric patients with idiopathic osteoporosis.

CONCLUSIONS

Idiopathic osteoporosis was the most frequent diagnosis of pre-menopausal osteoporosis in our unit. These patients showed lower BMI and higher femoral neck Z-scores than patients with secondary causes. A family history of osteoporosis and hypercalciuria were factors frequently associated with this disorder.

Secondary causes of osteoporosis

Secondary causes of bone loss are not often considered in patients who are diagnosed as having osteoporosis. In some studies, 20% to 30% of postmenopausal women and more than 50% of men with osteoporosis have a secondary cause. There are numerous causes of secondary bone loss, including adverse effects of drug therapy, endocrine disorders, eating disorders, immobilization, marrow-related disorders, disorders of the gastrointestinal or biliary tract, renal disease, and cancer. Patients who have undergone organ transplantation are also at increased risk for osteoporosis. In many cases, the adverse effects of osteoporosis are reversible with appropriate intervention. Because of the many treatment options that are now available for patients with osteoporosis and the tremendous advances that have been made in understanding the pathogenesis and diagnosis of the condition, it is important that medical disorders are recognized and appropriate interventions are undertaken. This article provides the framework for understanding causes of bone loss and approaches to their management.

Growth rate rather than gender determines the size of the adaptive response of the growing skeleton to mechanical strain

To determine whether male and female skeletons are equally responsive to mechanical load, the left ulnae in a group of juvenile male (n = 7), and age-matched female (n = 9) rats received a short daily period of controlled dynamic loading in vivo (1200 cycles at 2 Hz each day for 10 days) in addition to their normal exercise. Axial loads for each group were adjusted to engender a peak dynamic strain of -4000 microstrain at the medial face of the ulna midshaft, applied and released at a rate of +/-30,000 microstrain/sec. Fluorescent labels were administered at the start and finish of the loading period. Over the course of daily loading, the body mass of the male rats increased 2.5 times faster than that of the females (6.3 g/day vs. 2.5 g/day). The increase in periosteal interlabel bone area due to growth and normal exercise was also 2.5 times greater in the males than in the females. Both genders showed statistically significant (p < 0.05) increases in periosteal new bone deposition in the ulna of their loaded compared with their control limb. The pattern of osteogenic response was similar in males and females and featured increased mineral apposition rate on the lateral surface of the ulna, and arrest of modeling-drift-related resorption with its reversal to bone formation on the medial surface. In males, the absolute loading-related increase in bone area was six times greater than that in females. However, when the absolute size of the loading-related change in periosteal interlabel new bone deposition was expressed relative to that due to growth, there was no difference between males and females (Mean +/- SEM: 37 +/- 12% for males, 34 +/- 12% for females). These data confirm that the ulna of young actively growing rats of both genders responds to a short daily period of loading with an altered modeling response that involves increased bone formation and decreased resorption. Although the absolute amount of new bone formation stimulated by loading is greater in males than in females there is no difference between genders following correction for the higher rate of bone deposition seen in the males in association with their faster rate of growth.

Evaluating and managing osteoporosis in men

Osteoporosis affects approximately 10 million Americans; of these, 2 million are men. An estimated 3.5 million additional men are at risk of developing the disease. Individuals with osteoporosis commonly incur fractures of the spine, hip, and forearm. The clinical spectrum of osteoporosis is similar in men and women; however, differences exist in skeletal development, age-related bone loss, modifiable and nonmodifiable risk factors, and secondary causes. Prevention and early detection is achieved through identification of risk factors and secondary causes. Treatment options include risk factor reduction, correction of underlying disease, and use of pharmacologic and nonpharmacologic therapies.

How does quantitative ultrasound compare to dual X-ray absorptiometry at various skeletal sites in relation to the WHO diagnosis categories?

The World Health Organisation (WHO) has proposed a set of guidelines for the diagnosis of osteoporosis in adult women based on a measurement of bone mineral density (BMD) expressed as the number of SD below young adult mean (t-score). In this study, we investigated the number of subjects classified as either osteopenic or osteoporotic according to these guidelines using dual X-ray absorptiometry (DXA), at the hip, at the spine and at the lower forearm and quantitative ultrasound (QUS), at the heel. A total of 247 men, 209 postmenopausal women and 195 premenopausal women were included in the study. Furthermore, the study provides the first normative data showing the influence of sex, age and menopause on broadband ultrasound attenuation (BUA) and speed of sound (SOS), as measured by the DTU-one imaging ultrasound scanner. The difference between the number of patients classified into either diagnosis group by the investigated parameters is large ranging from 25.9% of the women being diagnosed as osteopenic by BUA at the heel to 43.0% by BMD at the femoral neck. For men, the same range is from 20.5% by BUA to 44.1% by BMD at the femoral neck. For the classification into the osteoporotic group, the range is from 2.5% by intertrochanteric BMD to 24.4% by BMD at Ward's triangle for women and from 0% by SOS to 29.0% by BMD at Ward's triangle for men. Using total hip BMD as the reference parameter to categorize the subjects as normal, osteopenic or osteoporotic, the agreement of the other parameters with this classification is assessed in terms of sensitivity and specificity. We conclude that there are significant differences in the classification of osteoporosis/osteopenia depending on the site measured and the technique used for the bone mass assessment. Furthermore, we suggest that development of technique and site specific cut-off values may increase the accuracy of the classification of osteoporosis/osteopenia in both men and women.

Background for studies on the treatment of male osteoporosis: state of the art

Male osteoporosis represents an important, although long underestimated, public health problem. Both in men and in women aging is accompanied by continuous bone loss and by an exponential increase in the incidence of osteoporotic fracture, with a female to male incidence ratio of about 2 to 3 to 1 in the elderly for hip and vertebral fractures. Morbidity after osteoporotic fractures appears to be more serious and mortality more common in men than in women. To date, no single treatment has been proved to be effective and safe in published prospective studies. The present report, based on a systematic search of the literature on male osteoporosis, summarises the state of the art on the clinical consequences of male osteoporosis and its risk factors, in relation to the present state of knowledge about female osteoporosis. This constitutes the background for the design of rational clinical development strategies for therapeutic interventions in male osteoporosis. From this review of the literature it is apparent that notwithstanding the existing sex differences in pathophysiology of osteoporosis and the difference in age-specific incidence of osteoporotic fractures, there are also important similarities between osteoporosis in women and men. The higher incidence of fracture in women than in men results from quantitative differences in risk factors rather than from different risk factors. Even though there are sex differences in bone geometry, incidence of fracture seems to be similar in men and women for a same absolute areal bone mineral density. However, the lack of data on the changes in fracture rates in men resulting from pharmacological intervention, leading to changes in bone mineral density or bone turnover, remains the main limitation for extrapolation of established treatment outcomes from women to men.

Vitamin D receptor gene start codon polymorphism (FokI) and bone mineral density in healthy male subjects

OBJECTIVE

The genetic factors determining peak bone mineral density (BMD) in men are not well characterized. Recent studies have investigated the relationship between the start codon polymorphism (SCP) of the vitamin D receptor (VDR) gene and BMD in different populations. We have now examined the relationship between SCP of the VDR gene and BMD in a group of healthy Caucasian men from the north-east of England.

SUBJECTS

Ninety-six healthy men (median age 50, range 40.0-77.0 years).

MEASUREMENTS

Analysis of the FokI genotypes of SCP of the VDR and measurements of BMD at the femoral neck and lumbar spine were performed.

RESULTS

FF, Ff and ff VDR FokI genotypes were found to have the highest, intermediate and the lowest lumbar spine BMD, respectively (Mean +/- SD, for FF 1.07 +/- 0.14, Ff 1.05 +/- 0.16 and ff 0.95 +/- 0.10 g/cm2). There was a significant difference in spine BMD between FF and ff genotypes (P < 0.05, analysis of variance [ANOVA]), but no such difference was apparent between Ff and ff (P > 0.05, ANOVA). Interestingly, there was no association between FokI polymorphism and femoral neck BMD (Mean +/- SD, for FF 0.85 +/- 0.12, Ff 0.87 +/- 0.15 and ff 0.83 +/- 0.15 g/cm2). The distribution of FokI VDR genotypes approached Hardy-Weinberg equilibrium and was similar to that reported for women from different ethnic groups, as the prevalence of FF and ff genotypes was 44% and 16%, respectively.

CONCLUSION

The study shows that in this population of healthy men there is a weak association between lumbar spine bone mineral density and FokI restriction fragment length polymorphism at the translation initiation site of the vitamin D receptor gene.

Predictors of milk consumption in a population of 17- to 35-year-old military personnel

OBJECTIVE

The purpose of this investigation was to survey an entire population of Air Force recruits (N = 32,144) regarding milk consumption and demographic and health-related factors that may predict milk consumption.

DESIGN

All subjects were required to fill out a 53-item health survey at the start of basic military training.

SUBJECTS/SETTING

All recruits who entered the US Air Force from August 1995 to August 1996 participated in this study (N = 32,144).

STATISTICAL ANALYSES PERFORMED

Potential correlates of milk intake were analyzed using Spearman rank order correlations and multiple linear regression. Variables were removed if they did not make a meaningful contribution to variance in milk intake. Because of skewed distributions, several variables were dichotomized (e.g., age: 17 to 24 vs 25 to 35 years).

RESULTS

In terms of milk consumption, 51.7% of the respondents reported intake of fewer than 1 serving per day; only 17.9% reported intake of 3 servings or more per day. Milk intake was positively associated with body weight and fruit/vegetable intake and negatively associated with age, education level, reported milk-related gastric distress, physical activity level, dieting frequency, and concern about weight. Gender (women reported lower intake) and ethnicity (minorities reported lower intake) were independently related to milk consumption. Of all respondents, 16.1% reported themselves to have milk-related gastric distress, but rates varied depending on age, gender, and ethnicity (ranging from 10.2% for younger non-Hispanic white men to 60.4% for older Asian men).

APPLICATIONS/CONCLUSIONS

Despite the efforts of large, costly campaigns designed to increase milk consumption, self-reported milk consumption in young adults is extremely low. Given the importance of dairy products as a major source of calcium in the American diet, dietetics practitioners should assess milk consumption among young adults to ensure sufficient calcium intake to maximize peak bone mass in this group.

Causes of secondary osteoporosis

Primary osteoporosis associated with menopause and aging is by far the most frequent metabolic bone disease. However, there are many patients who present with secondary osteoporosis due to identifiable causal factors and many others in whom a secondary factor contributes to the severity or progression of primary osteoporosis. Recognition of these secondary causes is particularly important for the prevention of further vertebral fractures, which are often progressive in secondary osteoporosis. This review will summarize the major factors that cause secondary osteoporosis and will discuss their pathogenetic mechanisms. While the most frequent cause is glucocorticoid excess, a number of other diseases, as well as drugs and nutritional deficiencies, can cause secondary osteoporosis. It is important to identify secondary osteoporosis both because of the differences in clinical expression due to different pathogenetic mechanisms and because there are often effective interventions that can add to the more general approach used in primary osteoporosis.

Exercise-induced loss of bone density in athletes

In athletes, the rarely identified malady of osteoporosis differs from other chronic effects of exercise. The most obvious difference is that hormonal imbalance leads to compensatory mechanisms that in turn lead to osteoporosis and increased incidence of fracture. Most research on this subject has dealt with women, because hormonal imbalances in women are easier to detect than those in men. Endurance athletes are known to have decreased levels of sex hormones, which can cause physiologic changes that lead to bone loss. This may result in relative osteoporosis despite the loading of the bone during exercise, which would normally increase bone mineral density. Premature osteoporosis may be irreversible, causing young athletes to become osteoporotic at an earlier age and have an increased risk of fracture later in life.

Secondary osteoporosis

Secondary osteoporosis is diagnosed when there is a well-established disease-related risk factor for fracture or low bone mass. Secondary osteoporosis is associated with a substantial minority of osteoporotic fractures in women perhaps with a majority of osteoporotic related fractures in men. This chapter does not review all the possible causes of low bone mass and fractures but picks out some of the more important causes of, with an emphasis on the main iatrogenic cause, that is corticosteroid induced osteoporosis. It also highlights some of the possible causes which could be avoidable. Where appropriate the methods of prevention and treatment of secondary osteoporosis are reviewed.

Hip bone mineral density is improved by high-impact aerobic exercise in postmenopausal women and men over 50 years

Fifteen men and women (six men) between the ages of 50 and 73 years were recruited to begin keep-fit classes. They were matched for sex, age, menopausal status and mass to 15 non-exercising controls. The keep-fit classes were two to three times a week and included high-impact exercise, including step and jumping exercises specifically to load the proximal femur and spine. Proximal femur, lumbar spine and total body bone mineral density (BMD) were measured at 0 and 12 months. Urinary pyridinoline (Pyr) and deoxypyridinoline (dPyr) crosslinks were measured every 6 months to assess bone resorption. Quadriceps isometric strength was measured every 6 months. BMD increased non-significantly at the femoral neck [1.57 (0.8)%] and Wards triangle [1.97 (1.4)%], and significantly at the greater trochanter 2.21 (0.9)% (P = 0.02) in the exercise group. Femoral neck BMD decreased by -1.9(0.8)% (P = 0.049) in the control group, which was significantly different from the change in the exercise group (P = 0.009). BMD did not change at the Wards triangle or trochanter in the controls. Lumbar spine BMD did not change in either group. Total body BMD did not change in the exercise group, but decreased by -0.79 (0.3)% (P = 0.02) in the controls. Following 6 months of the exercise classes. Pyr and dPyr crosslinks were significantly reduced [-19.0 (7.2)%; P = 0.0019 and -20.0 (7.7)%; P = 0.021 respectively]. There was no significant change in crosslinks after 1 year, and no change at any time in the controls. Quadriceps strength changed by 5.4 (3.7)% in the exercise group and by -6.9 (2.5)% (P = 0.01) in the control group after 12 months, being significant between groups (P = 0.008). This study suggests that high-impact, aerobic exercise in postmenopausal women and men over 50 years old is feasible and effective at maintaining muscle strength and increasing proximal femur BMD but not spine or total body BMD.

Mechanical loading and sex hormone interactions in organ cultures of rat ulna

The separate and combined effects of loading and 17 beta-estradiol (E2) or 5 alpha-dihydrotestosterone (DHT) on [3H]thymidine and [3H]proline incorporation were investigated in cultured ulna shafts from male and female rats. Ulnae were cultured and loaded to produce physiological strains in the presence or absence of 10(-8) M E2 or DHT. Loading engendered similar increases in incorporation of [3H]thymidine and [3H]proline in male and female bones. E2 engendered greater increases in incorporation in females than in males, and DHT greater increases in males than in females. In males E2 with loading produced increases in both [3H]thymidine and [3H]proline incorporation, which approximated to the arithmetic addition of the increases due to E2 and loading separately. In females E2 with loading produced increases greater than those in males, and substantially greater than the addition of the effects of E2 and loading separately. Loading with DHT in males also showed additional [3H]thymidine and [3H]proline incorporation. In females there was additional incorporation of [3H]proline, but not [3H]thymidine. The location of incorporation of [3H]thymidine and [3H] proline was consistent with their level of incorporation reflecting periosteal osteogenesis, in which case the early osteogenic effects of sex hormones are gender-specific when acting alone and in combination with loading. In males the effects of estrogen and testosterone add to, but do not enhance, the osteogenic responses to loading. In females testosterone with loading produces an additional effect on [3H]proline incorporation but no greater effect than loading alone on that of [3H]thymidine. In contrast, estrogen and loading together produce a greater effect than the sum of the two influences separately. Because premenopausal bone mass will have been achieved under the influence of loading and estrogen acting together, these findings suggest that the bone loss which follows estrogen withdrawal may result, at least in part, from reduction in the effectiveness of the loading-related stimulus on bone cell activity. This stimulus is normally responsible for maintaining bone mass and architecture.

The effect of socioeconomic status on bone density in a male Caucasian population

We have examined the effect of socioeconomic status (SES) on bone density (BMD) in 201 males, aged 20-60 years. Males of lower SES (groups 4-6 vs. 1-3) from the total sample had significantly higher BMD (p < 0.05) at L2-4 and femoral neck. The difference was small but was not explained by differences in age, weight, calcium intake, family history, activity, or smoking. 45% of SES 4-6 males were involved in manual labor compared with 11% of those in SES 1-3, however, this also did not appear to account for the difference.