Risk factors for spinal osteoporosis in men

The pathogenesis of osteoporosis

Changes in the calciotropic hormones with age contribute significantly to the pathogenesis of osteoporosis. In both postmenopausal (Type I) and senile osteoporosis (Type II) it is common to find reduced levels of serum 1,25-dihydroxyvitamin D and malabsorption of calcium. In Type I patients a reduced level of serum parathyroid hormone causes a real decrease in serum 1,25-dihydroxyvitamin D production and malabsorption of calcium, whereas in Type II patients the decline in 1 alpha-hydroxylase activity in the kidney causes a decline in serum 1,25-dihydroxyvitamin D which leads to malabsorption of calcium and secondary hyperparathyroidism. In the final analysis both pathways lead to bone loss. In some Type II patients there may be a decline also in the function or number of the vitamin D-binding receptors in the gut. Treatment of patients with vitamin D analogues, however, normalizes calcium absorption and improves calcium balance. The improvement in calcium balance reduces bone resorption and prevents further bone loss; in addition recent studies have shown that therapy with vitamin D analogues leads to a reduction in fracture incidence.

Alcohol decreases serum osteocalcin in a dose-dependent way in normal subjects

The acute effect of 25 and 50 g of alcohol on the variation in serum osteocalcin, a specific and sensitive marker of bone formation, and on serum cortisol and serum parathyroid hormone (PTH)(1-84) was calculated in 6 normal young adults. They were studied during three periods, each lasting from 4 p.m.-7:30 a.m. Alcohol was ingested between 4:15 and 5 p.m. during period two and three. Blood was taken at 4 p.m. and every 15 minutes from 4:30 til 6 p.m., followed by hourly sampling until 12 p.m. The last blood sample was taken after an overnight fast at 7:30 a.m. Initial and end values before and after alcohol ingestion did not differ significantly from control values. Repeated measures analysis of variance showed that 50 g of ethanol decreased serum osteocalcin significantly (P less than 0.02) and increased serum cortisol (P less than 0.05) during the 4-12 p.m. interval. The interaction of 50 g of ethanol on the variation in serum osteocalcin was already significant during the first 2 hours (P less than 0.02), where no significant effect on serum cortisol could be detected. Although insignificant, the same pattern was observed after 25 g of alcohol. There was no significant change in the variation of serum iPTH(1-84) during the 4-6 p.m. after alcohol intake. We conclude that 3-4 drinks of alcohol taken over 45 minutes decreases serum osteocalcin in a dose-dependent way. The time lag between changes in serum osteocalcin and cortisol indicates that the decrease in serum osteocalcin is not related to the increase in serum cortisol.

Current bone mass and body weight changes in alcoholic males

The relationships between current bone mass and changes in body weight were studied in 45 male veterans whose weights and heights at the time of enlistment into the Armed Forces over 40 years ago were obtained, and who were, or had been, chronic alcohol abusers. Those who lost and those who gained weight did not appear to differ in severity of alcoholism but differed in femoral neck cortical thickness, iliac crest trabecular bone volume, and lumbar bone mineral density, the former being significantly lower. Subjects with a hip fracture and those with spinal fractures are significantly lighter now, but were initially of similar weight to those without fractures. We conclude that maintenance of body weight protects against bone loss and fracture even in the presence of chronic alcoholism.

Hip fractures in young patients: is this early osteoporosis?

Hip fracture in patients under age 50 is rare, and is often not attributable solely to the energy of injury. Our aim was to determine if trabecular bone mineral density (BMD) is abnormal in young patients with hip fractures. We reviewed all hip fractures treated at our institution between 1979 and 1986 and contacted 20 patients under the age of 50 at the time of injury, all of whom wished to be studied. The mean age at the time of injury was 39 (range 24-47). Subjects were questioned for osteoporosis risk factors, classified by level of energy producing their injury, and then underwent quantitative computed tomography (QCT) bone densitometry of trabecular bone in the lumbar spine. Bone mineral density by QCT was below the mean for age in 90% of the patients, and was greater than 1 SD below the mean in 75%. Mean percentage BMD decrease from age-matched controls was 34% (P less than 0.005) in women and 19% (P less than 0.005) in men. There was an inverse correlation in the degree of BMD decrease and the energy level of injury. There was a direct correlation of the severity of BMD decrease and the cumulative number of osteoporosis risk factors. This investigation has found that 1-7 years following hip fracture, otherwise presumedly healthy young patients demonstrate a statistically significant decrease in spinal BMD from age/sex-matched controls. These data do not determine if osteopenia is the cause or the result of injury, nor do we wish to infer that measurement of bone density at one site can predict future fractures at other sites.(ABSTRACT TRUNCATED AT 250 WORDS)

The antiestrogenic effect of cigarette smoking in women

Epidemiologic results indicate that women who smoke cigarettes are relatively estrogen-deficient. Smokers have an early natural menopause, a lowered risk of cancer of the endometrium, and an increased risk of some osteoporotic fractures. Moreover, women who smoke may have a reduced risk of uterine fibroids, endometriosis, hyperemesis gravidarum, and benign breast disease. Several possible mechanisms for these effects have been identified. Smoking does not appear to be clearly related to estradiol levels, at least in postmenopausal women, although levels of adrenal androgens are increased. Moreover, smoking appears to alter the metabolism of estradiol, leading to enhanced formation of the inactive catechol estrogens.

Estrogen replacement therapy: indications, contraindications, and agent selection

Three groups of indications exist for postmenopausal estrogen use: relief of symptoms related to estrogen deficiency, osteoporosis prophylaxis and treatment, and cardioprotection. Estrogen replacement therapy enhances a woman's sense of well-being and reduces the morbidity, mortality, and health care costs associated with osteoporosis and atherosclerotic heart disease. There are a few absolute contraindications to estrogen replacement therapy. Many estrogen preparations are currently available in the United States. Establishing equivalencies among the different preparations is complicated by the many physiologic and pharmacologic effects of estrogens and the variety of treatment end points used. Most estrogens have the same biologic effect provided equivalent blood levels are achieved. Estrogen replacement therapy has proved beneficial to selected postmenopausal women.

Osteoporosis. Overcoming a costly and debilitating disease

As the aging population continues to increase, so too will the problem of osteoporosis. Because the first manifestation of the disease may appear at a stage when prevention is no longer possible, early education of both men and women regarding causes and treatment is desirable. Estrogen replacement is the most valuable tool in treating women and should be started within the first 3 years of menopause. Calcium alone or in combination with vitamin D is a safe preventive measure for women over age 40 and men over age 50.

Fractures in the men of a Veterans Administration Nursing Home: relation to 1,25-dihydroxyvitamin D

One hundred fifty-three men, age 48-96, 86% white, had resided in this Nursing Home for an average of 6.3 years (range 1.3-36) as of August 1984. At that time, we reviewed their medical charts to record the numbers and sites of fractures which had been diagnosed during the preceding 1 to 5 years of Nursing Home residence, the duration of this period depending on the duration of institutionalization. In addition, a clinical database was compiled comprising 70 attributes, including diagnoses, drugs, plasma (serum) chemistries, and measures of hematologic, nutritional, and functional status. Fractures during the studied period of Nursing Home residence had occurred in 24 of 153 men; six residents had experienced two or more fractures. Fracture rates in hip, spine, and wrist were 2564, 366, and 549 per 100,000 patient years, respectively. The total fracture rate, hip fracture rate, and limb fracture rate were five to 11 times higher than in the age-matched general population of white men in the United States; in Rochester, MN; in Dundee, England; in Oxford, England; or in Finland. Univariate statistical analysis showed that the rates for hip fracture or for fracture at any site were significantly associated with 13 attributes: directly with age, plasma somatomedin C, blood urea N, serum creatinine, serum uric acid, serum 25-hydroxyvitamin D (25-OH-D), degree of functional impairment, and chronic urinary tract infection, and inversely with serum 1,25-dihydroxyvitamin D [1,25-(OH)2-D], serum albumin, hematocrit, and hemoglobin. There was not a significant correlation with the number of falls/month which occurred during the 7 months after August 1984. After the effect of age was partialed out, somatomedin C, 25-OH-D, 1,25-(OH)2-D, and the diagnosis of urinary tract infection were still significantly related to the occurrence of fractures. The fact that Nursing Home fracture cases had significantly higher blood urea nitrogen and 25-OH-D, and significantly lower 1,25-(OH)2-D, than their non-fracture counterparts suggests that impaired renal production of the latter vitamin D metabolite contributed to the excessive rate of fractures.

Direct and sex-specific stimulation by sex steroids of creatine kinase activity and DNA synthesis in rat bone

A direct in vitro effect of 17 beta-estradiol (E2) was demonstrated on bone and cartilage cell energy metabolism. Sex-specific stimulation by E2 and testosterone was shown in diaphyseal bone of weanling rats. E2 (30 nM) caused, within 24 hr, a 70-200% increase in creatine kinase (CK; ATP:creatine N-phosphotransferase, EC 2.7.3.2) specific activity in ROS 17/2.8 rat osteogenic sarcoma cells, MC3T3-E1 mouse calvaria-derived cells, and rat fetal calvaria cells, and a 40% increase in rat epiphyseal cartilage cells. Stimulation of CK activity by E2 was dose and time dependent: in ROS 17/2.8 cells, a highly significant increase was found at 3 nM E2 and a greater than 100% increase in CK activity was found 1 hr after E2 administration. In female 20-day-old Wistar-derived rats, E2 (5 micrograms per rat) increased CK activity in diaphyseal bone by 82% within 1 hr of i.p. injection, with a maximal increase of 200% after 24 hr; neither the weakly estrogenic agonist 17 alpha-estradiol, testosterone, nor progesterone showed this effect. Conversely, in male rat diaphyseal bone, testosterone or dihydrotestosterone increased CK activity after 24 hr by approximately 100%, while E2 was ineffective. In epiphyseal cartilage, both E2 and testosterone increased CK activity. Stimulation of CK activity by sex hormones was paralleled by significant increases in [3H]thymidine incorporation into DNA. Therefore, it is possible that direct sex-specific actions of gonadal steroids may contribute to stimulating bone growth and maintaining balanced bone turnover.

Bone mass in hirsute women with androgen excess

The spinal and femoral bone mass of 32 hirsute women with oligomenorrhoea and androgen excess was measured using dual photon absorptiometry and compared with the bone mass of 32 control women with regular menstrual cycles. Despite significantly lower oestradiol levels in the hirsute population there was no significant difference in the bone mass. Furthermore there was no significant difference in bone mass in five hirsute women with undetectable levels of oestradiol. It is concluded that androgen excess can maintain normal bone mass in the face of low or undetectable oestradiol levels.

Spinal osteoporosis in men

In 94 men with crush fracture, 40 were found to have primary osteoporosis. Cross-sectional measurements of a number of variables related to bone in these 40 patients were compared to the values in various groups of healthy men aged 20-96. In healthy men, metacarpal and femoral cortical area/total area, bone volume, osteoid surfaces, seam and trabecular width, plasma dihydroepiandrosterone and estrone, and radiocalcium absorption fell with age, whereas eroded surfaces, trabecular number, urine hydroxyproline and calcium/creatinine ratios, plasma alkaline phosphatase, estradiol, androstenedione, cortisol and testosterone remained constant with age. As compared with healthy men, men with primary osteoporosis had reduced femoral cortical area/total area (P less than 0.05), and Singh grade (P less than 0.001) and in seven there was a history of forearm or femoral fracture. On iliac crest biopsy, bone volume (P less than 0.001) and trabecular number (P less than 0.01) were decreased. Plasma alkaline phosphatase (P less than 0.02) was increased but urine hydroxyproline and calcium excretion were not significantly raised. Calcium balance was negative due to failure of absorption to match urinary calcium loss and radiocalcium absorption (P less than 0.01) and plasma 1,25-dihydroxyvitamin D (P less than 0.05) were reduced.

Ethanol reduces bone formation and may cause osteoporosis

INTRODUCTION

The etiology of ethanol-associated osteopenia is not fully understood. In order to define the role of ethanol in the pathogenesis of hepatic osteodystrophy, we compared two groups of alcoholic patients with histologically established alcoholic liver disease.

PATIENTS AND METHODS

Twenty-eight patients currently drinking ethanol ("drinkers") and 12 claiming not to have consumed any ethanol for at least six months ("abstainers") were enrolled in the study. In addition, 35 non-alcoholic control subjects without clinical or biochemical evidence of liver disease were also studied. Bone mineral density and various biochemical and hormonal values were measured in each subject; iliac crest biopsies were taken under local anesthesia in the patients and under general anesthesia in the control subjects.

RESULTS

Forearm bone mineral densities, spinal bone mineral densities, and iliac crest cancellous bone areas were significantly lower in the alcoholic patients compared with control subjects (p less than 0.01 for all measurements), but these values did not differ between the drinkers and the abstainers. The drinkers, however, had significantly less osteoblastic activity than the abstainers, as assessed by dynamic bone histomorphometry (p less than 0.001). Serum bone Gla-protein concentrations were higher in the abstainers than in the drinkers (p less than 0.001). No differences were seen relating to histologic parameters of bone resorption, although the alcoholic patients who had lower serum free testosterone concentrations than the control subjects also had higher urinary hydroxyproline excretion rates.

CONCLUSION

These data suggest that ethanol may be responsible for osteoblastic dysfunction resulting in diminished bone formation and reduced bone mineralization.

Does smoking protect against osteoarthritis?

While studying knee osteoarthritis (OA) in the first Health and Nutrition Examination Survey, we unexpectedly found a protective association between smoking and OA. After adjustment for age, sex, and weight, smokers had a significantly lower rate of OA than did nonsmokers, and heavier smokers were less likely to have the disease than were light smokers. To test this association in a separate study and see if it was due to confounding factors, we looked at the Framingham Osteoarthritis Study, a study of elderly members of the Framingham Heart Study cohort. We evaluated whether the presence of knee OA in 1983-1985 was related to smoking status at the first Framingham examination, 36 years earlier. Subjects who had been smokers at examination 1 had a lower rate of OA (190 of 679, 28%) than did nonsmokers (276 of 736, 37.5%). In an analysis adjusted for age, sex, and weight, heavy smokers had a modestly lower risk of developing knee OA than did nonsmokers (relative risk 0.81). Also, the adjusted risk of severe OA was less in heavy smokers than in nonsmokers (relative risk 0.73). The negative association with OA persisted when we examined the average cigarette consumption over the first 10 years of the Framingham study. Furthermore, after controlling for age, sex, weight, knee injury history, sports activity history, physical activity level, coffee and alcohol consumption, and weight change after examination 1, and after modeling weight and age in a nonlinear manner, smoking remained a significant protector against later knee OA. It appears that smoking or some unidentified factor correlated with smoking modestly protects against the development of knee OA.

Effects of tobacco use on axial and appendicular bone mineral density

Tobacco use has been identified as being a risk factor for the development of osteoporosis. While some data have suggested an effect on peripheral bone mass there are little previous data examining the role of tobacco use in axial skeletal bone loss. We examined tobacco use in relation to lumbar spine and proximal femur bone mineral density and forearm bone mineral content in 203 women. Data from identical twin pairs, comprising a subgroup of the larger group as well as a small number of male twin pairs, was also analyzed. The data show a difference in lumbar and proximal femur BMD of 0.03 and 0.06 g/cm2 respectively between smoking and nonsmoking identical twins. There was however no difference in the cross-sectional studies and no significant deleterious effect detected of tobacco use on forearm bone mineral content. The effect of smoking on lumbar and proximal femur bone mineral density, in identical twins discordant for tobacco use, was equivalent on average to 3 to 4 years of normal postmenopausal bone loss.

Fracture of the upper end of the femur is not associated with familial fracture disposition

Based on the population of the city of Malmö, Sweden, we performed a retrospective cohort study. By choosing patients who had fractures of the upper end of the femur in the 1950s as an indication of senile osteoporosis, and by studying the roentgenographic records of their children from the 1950s and on we concluded that this type of osteoporosis is not a condition that is aggravated in certain families. Offspring of parents who had a hip fracture in the 1950s are not more prone to have fractures than a control group.

Fractures and lifestyle: effect of cigarette smoking, alcohol intake, and relative weight on the risk of hip and forearm fractures in middle-aged women

Cigarette smoking, alcohol consumption and low relative weight are often cited as risk factors for osteoporosis. In a prospective cohort study of 96,508 middle-aged nurses 35 to 59 years of age we found that smoking was not a risk factor for hip and forearm fracture. Women who drank more than 15 grams of alcohol per day and whose relative weight was less than 21 kg/m2 were at increased risk of fractures, but these risk factors were not independent. Only the combination of alcohol intake and thinness substantially increased the likelihood of fracture. The low weight women consuming more than one drink per day comprised but 4 per cent of our population of middle-class women and sustained 6 per cent of the fractures.

Calcium status and calcium-regulating hormones in alcoholics

To elucidate effects of chronic ethanol consumption on clinical chemical parameters reflecting overall calcium homeostasis 34 hospitalized male alcoholics and 35 age-matched controls were studied during the winter season. Serum concentrations of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 were reduced by 28% (p less than 0.01) and 24% (p less than 0.02) among the alcoholics as compared to the controls, respectively. Dietary intake of vitamin D3 did not differ significantly between the groups. The calcium level was below lower limit of reference in nine alcoholics (26%). Serum concentrations of parathyroid hormone and phosphorus were within normal ranges in both groups, and no differences were observed in levels of magnesium, vitamin D-binding protein, calcitonin, or alkaline phosphatase. In conclusion, it is possible that the activities of enzymes crucial in vitamin D3 metabolism may be altered in alcoholics.

Atraumatic vertebral deformities in elderly males

Little information is available on the prevalence of vertebral wedge deformities in elderly males; therefore, 116 ambulatory male volunteers age 65 and over were studied with lumbar and thoracic radiographs. Each patient was questioned concerning a history of high-energy spinal trauma. Those having 25% or greater anterior vertebral wedging were identified. Eleven percent of the males had at least one 25% atraumatic wedge deformity, and 2% had two or more such vertebra. These results are discussed in relation to the few published studies on this topic.

Vertebral compression fractures and mineral metabolism in chronic obstructive lung disease

Chronic obstructive lung disease has been reported as a cause of osteoporosis, though whether this association is due to the disease itself or to corticosteroid treatment has not been elucidated. We studied 44 male patients with chronic obstructive lung disease (mean (SD) FEV1 39% (14%) of predicted normal) who were not having long term corticosteroids. No differences in a vertebral deformity score or in metacarpal index were found between them and a control group of similar age. Indices of bone formation (serum osteocalcin) and bone resorption (urinary hydroxyproline) were normal and parathyroid hormone and 1,25-dihydroxyvitamin D were also normal. Serum 25-hydroxyvitamin D was decreased, indicating depleted vitamin D. Calcitonin concentrations were higher in the patient than in the control group of the same age. There was no increase in the prevalence of osteoporosis in patients with chronic obstructive lung disease who had not received long term corticosteroid treatment. Increased concentrations of calcitonin may protect the skeleton from the detrimental effect of hypovitaminosis D.

Osteopenia

Osteopenia in the elderly is responsible for 1.3 million fractures per year in the United States. The acute care costs associated with this disorder are between $6 and $10 billion dollars annually. Although much has been learned over the last few years of the factors that predispose patients to osteoporosis and how these factors may be avoided, the precise pathophysiologic mechanisms for bone loss remain obscure. Significant technological advances have been made in the 1980s in the development of noninvasive methods for measuring bone mineral density that give indirect assessments of bone mass. However, these methods are very controversial, are not suitable for mass screening for detecting subjects potentially at risk, and have a limited place in routine clinical care. Osteoporosis is characterized by thinning and fragmentation of trabecular bone, which is probably irreversible when it is far advanced. The most reasonable therapeutic approach may be prevention, which can be achieved in many patients by estrogen therapy in the perimenopausal years and insuring an adequate dietary calcium intake, particularly in adolescents and in the elderly. Physical activity throughout life is also likely to be important in maintaining adequate bone mass. It is important to differentiate osteoporosis from other causes of osteopenia, for example, osteomalacia, primary hyperparathyroidism, and malignant diseases such as myeloma, since these bone diseases have a different natural history, pathophysiology, and treatment.

Human aging: usual and successful

Research in aging has emphasized average age-related losses and neglected the substantial heterogeneity of older persons. The effects of the aging process itself have been exaggerated, and the modifying effects of diet, exercise, personal habits, and psychosocial factors underestimated. Within the category of normal aging, a distinction can be made between usual aging, in which extrinsic factors heighten the effects of aging alone, and successful aging, in which extrinsic factors play a neutral or positive role. Research on the risks associated with usual aging and strategies to modify them should help elucidate how a transition from usual to successful aging can be facilitated.

Bone density of the radius, spine, and hip in relation to percent of ideal body weight in postmenopausal women

Bone mineral content (BMC) and bone mineral density (BMD) of the spine (L2-L4) and hip (at femoral neck, Ward's triangle, and greater trochanter sites) were determined by dual-photon absorptiometry (DPA), and of the radius by single-photon absorptiometry (SPA) in healthy postmenopausal women aged 40-70 years. The relationships of BMC and BMD to years since menopause were examined separately in 97 women who were above 115% of ideal body weight (IBW) and in 128 women below. The heavier women had significantly greater mean BMC and BMD at each site than did the normal-weight women. In the normal-weight women, there was a significant negative correlation between BMD and years since menopause at each measurement site except the greater trochanter. In the obese women, BMD decreased with increasing years since menopause at the radius site only and BMC declined with increasing years after menopause at the hip (femoral neck and Ward's triangle region) as well as the radius. Thus, body size is a significant determinant of BMD in this population. The pattern of loss of BMD from Ward's triangle and femoral neck regions of hip are similar to that of the spine. The BMC and BMD findings in the hip suggest that remodeling occurs at this weight-bearing site which has a favorable effect on bone strength.

Pathogenesis of osteoporosis

Five major risk factors for osteoporosis have been identified: age, initial bone density, the menopause, bioavailability of calcium, and sporadic factors. Age appears to be the major determinant of bone mass. During a lifetime, a woman will typically lose 50% of her trabecular bone and 35% of her cortical bone. Bone density is affected by the amount of bone developed during growth, as well as by the subsequent rate of loss. Strong evidence has shown that loss of ovarian function leads to an accelerated phase of bone loss. Bone turnover rates increase, but resorption occurs faster than formation. This acceleration slows with time, reaching the level of the underlying slower phase of bone loss approximately 10 years after the onset of menopause. The role of calcium intake in preventing osteoporosis remains a matter of debate. Other factors shown to affect the risk of osteoporosis include low weight, smoking, alcohol intake, and degree of physical activity. The fact that not all postmenopausal women develop osteoporosis suggests that other, as-yet-undetermined factors may play a role in this condition.

Deranged bone mineral metabolism in chronic alcoholism

Chronic alcoholic subjects may suffer from osteopenia with either osteomalacia or osteoporosis as the main histologic finding. The reasons may be multifactorial, including nutrition, direct effects of alcohol on bone, and deranged liver function. Seventeen asymptomatic subjects with chronic alcoholism were studied. Serum PTH (carboxyl and midmolecule fragments), 25 hydroxyvitamin D [25(OH)D], 1-25 dihydroxyvitamin D [1-25(OH)2D], and ionized calcium were measured in each subject. In addition to these tests, we employed a sensitive technique of dual photon absorptiometry to measure vertebral bone density and a radioimmunoassay of serum bone gla protein (BGP) to estimate osteoblast function. Our results show that subjects suffering from chronic alcoholism had significantly lower serum 25(OH)D and higher ionized calcium, BGP, PTH (midmolecule) and 1,25(OH)2D while four patients had bone density values below the fracture threshold (0.96 g/cm2). These findings demonstrate that asymptomatic patients with chronic alcoholism have deranged bone mineral metabolism including abnormal BGP and some subjects may even have abnormal dual photon absorptiometry measurements. These particular subjects may be at risk in the future for developing osteopenia and consequent vertebral compression fractures.

Marked decline in trabecular bone mineral content in healthy men with age: lack of association with sex steroid levels

To define the association of age-related changes in bone mineral content to gonadal function in normal men, we measured radial (largely cortical) and vertebral (largely trabecular) bone mineral content (BMC), testosterone (total and free), estrone and estradiol-17B levels in 62 healthy subjects, ages 30 to 92. Radial BMC fell 2 to 3.4% per decade but vertebral trabecular BMC declined more rapidly at 12% per decade. Of the sex steroids measured the only statistically significant change occurred in free testosterone levels which decreased with age (r = -.57, P less than .0001). Free testosterone levels correlated significantly with trabecular vertebral BMC (r = .458, P less than .0002) but not with bone mineral measures at the predominantly cortical radial sites. However, by multiple regression analysis free testosterone did not add to the effect of age on vertebral BMC. There were no associations of total testosterone, estrone, or estradiol levels to bone mineral content at any of the three sites measured in these healthy men. Age-related declines in male gonadal function do not appear to be of primary importance in male age-related bone loss.

Dietary fibre and mineral metabolism

Current dietary recommendations urge, inter alia, an increased consumption of fibre-containing foods. Some experimental studies made on various animals and man indicate that the associated increases in intakes of fibre and phytic acid may prejudice mineral status respecting calcium, magnesium, iron and zinc. An examination has been made of the experimental evidence, also of the epidemiological evidence on numerous types of populations, past and present, developing and developed. It has been concluded that diets high in fibre, characteristically do not have meaningful ill effects on well-being or unequivocally enhance morbidity. In particular populations in certain regions where deleterious effects have been reported it is judged that local factors, not wholly understood, are in operation. In assessing the extent of the benefit to be derived from the dietary changes urged, results must be viewed holistically and not in isolation. It is believed that the beneficial effects respecting reduced pronenesses to various degenerative diseases are likely to far outweigh the possible adverse effects of reduced bioavailability of mineral nutrients.

Postmenopausal osteoporosis

Osteoporosis is a major public health problem, particularly for the postmenopausal woman. With the withdrawal of estrogen at menopause, bone resorption begins to exceed formation in remodeling cycles and bone mass is inexorably lost. Clearly, preventing postmenopausal osteoporosis is the aim of management. Individuals with risk factors for developing this condition should have noninvasive bone density determination and should be considered for preventive regimens. Therapeutic options for prevention include calcium, estrogen, and exercise. Once osteoporosis is established, therapeutic options may include those listed previously as well as fluoride and other modalities currently under investigation.

Increase in bone mass after treatment of hyperprolactinemic amenorrhea

Hyperprolactinemia occurs in 25 to 30 percent of young women with amenorrhea, and this condition is known to be associated with osteopenia. To determine whether the osteopenia is affected by treatment of hyperprolactinemia, we studied 32 women with hyperprolactinemic amenorrhea prospectively for 12 to 72 months to investigate the effects of sustained hyperprolactinemia or return of gonadal function on bone mass. We studied 18 patients using direct photon absorptiometry before and after normalization of serum prolactin levels. Initial bone densities ranged from 0.55 to 0.77 g per square centimeter (mean +/- 1 SD, 0.64 +/- 0.05)--densities significantly lower (P less than 0.001) than those of controls (0.71 +/- 0.04 g per square centimeter). After therapy, bone density increased significantly (P less than 0.001), to 0.67 +/- 0.05 g per square centimeter, but remained lower (P less than 0.05) than normal. Fourteen patients were followed without therapy. Their initial bone densities ranged from 0.62 to 0.75 g per square centimeter (mean, 0.67 +/- 0.04)--values significantly lower (P less than 0.02) than those in controls. There was a significant decrease (P less than 0.002) in bone density over time in this group. We conclude that (1) treatment of hyperprolactinemia increases bone mass in most amenorrheic women with osteopenia, (2) normalization of serum prolactin levels in such women is associated with prevention of bone loss, and (3) a subset of untreated women with hyperprolactinemia have progressive osteopenia, which could have adverse long-term health consequences.

Chronic alcoholism. Frequently overlooked cause of osteoporosis in men

A radiographic survey was made of 96 fully ambulatory male patients who were admitted to a rehabilitation center for patients with chronic alcoholism in an attempt to estimate the incidence of skeletal demineralization in these patients. The age of the patients ranged from 24 to 62 years. Forty-five of the 96 male patients, or 47 percent of this group, showed radiographic evidence of extensive bone loss. Fourteen or 31 percent of these 45 patients with bone loss were relatively young (age 31 to 45 years), and half of this group of 14 patients were less than 40 years old. The majority of the 45 patients with radiographic evidence of osteoporosis, namely, 31 patients or 69 percent, were older and ranged in age from 46 to 62 years. One third of the patients in this group were less than 50 years old. The radiographic survey of the 96 patients indicates the high incidence of extensive bone loss, most likely osteoporosis, in relatively young and middle-aged ambulatory men with chronic alcoholism. In 12 additional patients with chronic alcoholism who were observed in the Metabolic Research Ward, and who were not part of this survey, bone biopsy specimens confirmed the radiographic diagnosis of osteoporosis.