The effect of glucocorticoids on bone mass in rheumatoid arthritis patients. Influence of menopausal state

We studied 97 patients with definite or classic rheumatoid arthritis (RA). Fifty-four patients (19 premenopausal women, 25 postmenopausal women, and 10 men) had been treated with low-dose glucocorticoids for at least 12 months (mean dose less than 10 mg/day). The remaining 43 patients (15 premenopausal women, 17 postmenopausal women, and 11 men) had been treated with penicillamine, and served as a patient control group. The distal forearm bone mineral content (BMC) was measured in all patients by single photon absorptiometry using 125I, and the total body bone mineral (TBBM) was measured in 61 patients by dual photon absorptiometry using 153Gd. Compared with normal controls, both treatment groups had significantly decreased BMC and TBBM (0.01 less than P less than 0.001). When the patients were stratified according to pre- and postmenopausal state, we found significantly lower BMC and TBBM values in the premenopausal glucocorticoid-treated women than in penicillamine-treated women. However, no differences in BMC and TBBM values were found in the corresponding postmenopausal groups. In the premenopausal women treated with glucocorticoids, the duration of treatment and cumulative dose correlated with BMC. No such correlations were found in the postmenopausal women. We conclude that 1) RA is associated with loss of bone mass, 2) systemic glucocorticoid treatment further aggravates the bone loss, 3) in postmenopausal RA patients, the bone loss resulting from menopause and from the disease itself is not accelerated by low-dose glucocorticoids, and 4) in premenopausal RA patients, however, the bone mass is significantly affected by glucocorticoid treatment. We therefore suggest that these factors be considered when prescribing glucocorticoids, in order to minimize the bone loss.     

Does a single local absorptiometric bone measurement indicate the overall skeletal status? Implications for osteoporosis and osteoarthritis of the hip

Summary Regional bone mineral content (BMC) and density (BMD) (head, arms, chest, spine, pelvis, legs) of a total body dual photon¹⁵³Gd absorptiometry (DPA) scan were measured in 20 healthy postmenopausal women, 27 postmenopausal women with hip fracture, and 17 postmenopausal women with osteoarthritis of the hip. In addition, local BMC and BMD were measured in the proximal and distal regions of the distal forearm (BMC_prox, BMD_prox, BMC_dis, BMD_dist) by single photon absorptiometry (SPA); and in the lumbar spine (BMC_L2-L4 and BMD_L2-L4) by¹⁵³Gd DPA. The overall impression was a reduction of bone mass in hip fracture patients compared with healthy controls and an increase in the bone mass of osteoarthritic patients. These results were valid using both regional values of the total body scan, and local forearm and lumbar spine measurements, and statistically significant using one-way analysis of variance. There were, however, also significant within-group between-region differences (one-way analysis of variance), showing that the bone mass of the pelvis and legs in hip fracture patients was more reduced than in the remaining skeleton; in osteoarthritic patients it was not increased but rather unchanged or slightly reduced. The differences between the level of the three local measurements (BMD_prox BMD_dist BMD_L2-L4), on the one hand, and the level of the six regional BMD values, on the other hand, were investigated by the two-way analysis of variance: local measurements = rows; regional values = columns. This analysis showed that none of the three local measurements was statistically better than the other two in predicting the overall level of skeletal bone mass as judged by the six regional values. We conclude that serious osteoporotic bone loss has a generalized nature, however, with a tendency towards lower values in the regions affected by fracture (viz: low bone mass in the legs of femoral neck fracture patients). Osteoarthritis may be associated with a high bone mass in most areas, but low values in the affected regions. Local lumbar spine measurement of bone mass by DPA is not superior to local forearm measurement of bone mass by SPA in predicting the nature of overall osteoporotic or osteoarthritic bone change.     

Relationship between Bone Mineral Content and Frequency of Postmenopausal Fractures

To elucidate the relationship between bone mineral content (BMC) and the frequency of postmenopausal fractures, we performed an epidemiologic investigation in a representative sample of 70-year-old women. Anamnestic data concerning postmenopausal fractures due to minor trauma were recorded and lateral X-rays of the spine were taken for evaluation of spinal fractures. BMC was measured by ¹²⁵I photon absorptiometry. The 285 women studied were allocated into quintiles according to their BMC value. In 77 women, there were 131 definite osteoporotic fractures (i.e., spinal crush, and fracture of the hip, proximal humerus, and distal forearm), and in 48 women, there were 162 other non-violent fractures (i.e., spinal wedge and other long bone fractures). The frequencies of osteoporotic fractures varied inversely with the mean BMC values for each quintile (r=0.959, p<0.01). The difference in frequency of osteoporotic fractures between the first and fifth quintiles was highly significant (p > 0.001). In contrast, other non-violent fractures appeared to be unrelated to BMC. It is concluded that low BMC levels predispose to osteoporotic fractures.     

Measurement of the subcutaneous fat in the distal forearm by single photon absorptiometry

The influence of subcutaneous fat on single photon (125I) absorptiometry (SPA) measurement of bone mineral content of the distal forearm was investigated. A fat correction model was tested by measurements on eight lean subjects with different amounts of porcine fat around their forearm, and further validated from measurements on 128 females. In addition, it is shown that the fat content in the distal forearm can be measured by SPA with a short-term precision at 1.9% in an obese subject and that it correlates well with total body fat (r2 = .7) measured by dual photon absorptiometry, skinfold thickness (r2 = .5), and body mass index (r2 = .6). By using this method in a double-blind placebo-controlled trial, hormonal substitutional therapy significantly decreased the forearm fat content without affecting the body weight in postmenopausal osteoporotic women.     

New methods for identifying “at risk” patients for osteoporosis

Clinical Rheumatology - Bone loss was determined in 178 women in the early postmenopausal period by photon absorptiometry measurement of forearm bone mineral content (BMC) every three months for...     

Osteocalcin and bone mineral content in rheumatoid arthritis

Summary Abnormal bone metabolism was reported in rheumatoid arthritis (RA). In order to evaluate the interest of serum osteocalcin, also called bone GLA- protein (BGP), to assess bone metabolism in RA, we studied 20 postmenopausal RA out- patients and 20 matched controls. Nine patients were treated with low- dose corticosteroids (C₊)for at least one year (< 10 mg/day, prednisolone equivalent), the remaining 11 (C–) received non-steroidal anti-inflammatory drugs (NSAID). The distal and proximal forearm bone mineral content (BMC) was measured by single photon absorptiometry, the vertebral BMC was measured by dual photon absorptiometry. A trend to low BGP was observed in the C+ group. The lowest values were observed in patients with vertebral fractures. Compared with controls, both RA groups had similar low significant BMC at the forearm sites. At the vertebral sites, the bone mineral content decrease observed in the two groups, was more marked in the C+ group. From our results, BGP did not appear as a useful index of osteoporosis in RA, except in some patients with vertebral fractures, treated with low-dose corticosteroids.     

REDUCED FOREARM BONE MINERAL CONTENT AND BIOCHEMICAL EVIDENCE OF INCREASED BONE TURNOVER IN WOMEN WITH EUTHYROID GOITRE TREATED WITH THYROID HORMONE

We used single-photon absorptiometry to assess forearm bone mineral content (BMC/BW) (arbitrary units normalized for bone width) at a proximal site (PBMC/BW) and at a more distal site (DBMC/BW) in 60 women treated with 25-50 micrograms T3 or 50-100 micrograms T4 for euthyroid goitre, in 13 untreated goitre patients, and in 2 controls matched for age and menopausal state for each goitre patient. BMC/BW was not significantly different between untreated goitre patients and controls. In 36 premenopausal patients, treated for 5.8 +/- 5.4 years (mean +/- SD) a slight decrease in PBMC/BW of about 5% compared to controls to controls was observed (PBMC/BW 1.42 +/- 0.19 vs 1.49 +/- 0.13, P less than 0.05). In 24 postmenopausal patients, treated for 10.0 +/- 5.8 year, a 20% deficit in BMC/BW compared to controls was found (DBMC/BW 0.80 +/- 0.18 vs 1.06 +/- 0.20, P less than 0.001 and PBMC/BW 1.14 +/- 0.20 vs 1.42 +/- 0.19, P less than 0.001). Biochemical indices of bone metabolism in 43 pre and post-menopausal patients and 43 controls showed in the patients a higher serum alkaline phosphatase activity (AP) (P less than 0.01 and P less than 0.05 and serum osteocalcin (NS and P less than 0.05). AP was negatively correlated with TSH levels and, in postmenopausal patients, with DBMC/BW and PBMC/BW. Our results suggest that treatment of euthyroid women with moderate doses of thyroid hormone increases bone turnover with clear adverse effects on bone mineral status in postmenopausal patients.     

Relationship between Local and Total Bone Mineral Content after Gastric Surgery

We compared the total body bone mineral mass (TBBM), assessed by the dualphoton technique, with the local bone mineral mass (BMC), measured by single- photon absorptiometry, in 27 ulcus patients treated by either gastric resection or parietal cell vagotomy. Except for raised concentrations of serum alkaline phosphatase in the Billroth I resection group, the biochemical findings and the measurements of bone mass (local and total) were normal. A highly significant correlation between local and total body bone mineral mass was found in both patients (r = 0.84) and controls (r = 0.91). Since the relationship between these two measurements is identical in the patient population and in the age-matched control group, it is concluded that the local BMC may be useful to estimate total bone mass after gastric surgery.     

Treatment of post-menopausal osteoporosis with a combination of growth hormone and pamidronate: a placebo controlled trial

OBJECTIVE It is known that growth hormone can Induce accelerated bone turnover in GH deficient people as well as healthy elderly people. In this study we examined the effect of recombinant human GH (rhGH) on bone mineral mass and bone turnover in the presence of the bone resorption inhibiting agent, pamidronate. Effects on body composition were also studied. METHODS Twenty-one post-menopausal osteoporotic women were treated with the bisphosphonate pamidronate during 12 months. During the Initial 6 months rhGH (0.0675 IU/kg, 3 times/week) was administered In a placebo controlled fashion (10 vs 11 patients). MEASUREMENTS Bone mineral Content (BMC) of the lumbar spine and femoral neck was measured with dual-energy X-ray absorptiometry and BMC of the distal and proximal forearm with single-photon absorptiometry. Body composition was measured with bioelectrical Impedance and total body dual-energy X-ray absorptiometry. Serum IGF-I and biochemical indices of bone turnover were also measured. RESULTS The group treated with rhGH showed a two to three-fold Increase In serum IGF-I levels. No effects on bone mineral mass were observed in the group treated with rhGH, either after the Initial 6 months of treatment with rhGH or after the total period of 12 months. In women treated with pamidronate, however, a consistent increase of about 5% at the lumbar spine and somewhat less in the distal forearm was reached from 6 months onwards. In neither group was any change observed in BMC at the femoral neck or forearm. Compared to baseline, the biochemical measurements of bone turnover showed a decrease of about 50% in the pamidronate treated group, but this effect was blunted in the group additionally treated with rhGH. The body composition measurements showed clear effects of rhGH administration: a decrease in fat mass of about 5% and an increase In lean body mass of about 3%. However, these effects disappeared after the treatment with rhGH was stopped and both fat mass and lean body mass returned to Initial values. CONCLUSIONS The present study suggests that treatment with rhGH blunted both the pamidronate induced accumulation of bone mineral mass and the reduction of biochemical markers of bone turnover. Furthermore, the positive effect of rhGH on body composition disappears completely after cessation of treatment with rhGH.     

Determinants of bone mass in postmenopausal women

Eighty white women, mean age 52 years, within one to six years postmenopausal, were studied to examine the relationship of various factors to bone mass. Forty-four of the women had annual measurements of bone mass, so that the rate of bone loss could be determined. Bone mass was measured by total body neutron activation analysis and photon absorptiometry of the distal radius (total body calcium [TBCa] and bone mineral content [BMC], respectively). Breast-feeding and pregnancy were noted to be associated with higher bone mass; those with lower BMC and/or TBCa tended to have higher serum alkaline phosphatase levels, lower testosterone levels, and more years since the cessation of menses. The rate of bone loss from the radius was greater in those with higher parathyroid hormone levels; those with reduced dietary intake of calcium and lower 25-hydroxyvitamin D levels had a greater rate of loss of TBCa.     

BONE MINERAL CONTENT IN PATIENTS WITH RHEUMATOID ARTHRITIS: RELATIONSHIP TO LOW-DOSE STEROID THERAPY

Bone mineral content (BMC) of the distal forearm was measuredby single photon absorptiometry in 142 patients with rheumatoidarthritis (RA) of whom 27/54 men and 44/88 women received low-dosesteroid therapy (<10 mg/day). To study the effect of steroidtherapy a case-control analysis was undertaken in patients matchedfor age, sex and disease duration. Steroid therapy was associated with a reduced BMC in men (1.16±0.29versus 1.32±0.23; P<0.05) and postmenopausal (0.76±0.24versus 0.91±0.25; P<0.02) but not premenopausal women(1.1±0.28 versus 1.1±0.17). Symptomatic fractureswere more common in steroid-treated patients than in those whohad not received steroids (10/71 versus 2/71; P<0.05). Serum osteocalcin, an index of bone formation, was measuredin 106 cases. It tended to be higher in patients with RA thanin controls but the values observed in steroid and non-steroidRA groups did not differ significantly. We conclude that low-dose steroid therapy is associated withincreased bone loss and numbers of fractures in patients withRA but this does not apear to be the result of a simple defectin bone formation. KEY WORDS: Osteoporosis, Fractures, Osteocalcin, Single photon absorptiometry     

Evaluation of bone mineral density of the peripheral skeleton in pre- and postmenopausal women with newly diagnosed endogenous Cushing's syndrome

OBJECTIVE: Cushing's syndrome (CS) is a well recognized cause of bone loss. Although many previous studies have shown decreased bone mineral density (BMD) in the lumbar spina and proximal femur of patients with endogenous CS, so far, the data estimating BMD in their peripheral skeleton are sparse. The aim of the present study was to evaluate BMD in the forearm and heel of women with newly diagnosed CS and to investigate its possible correlation with serum osteocalcin (BGP) and 24-hour urinary free cortisol levels (UFC). PATIENTS AND METHODS: BMD in the forearm (distal and ultradistal area) of 29 (13 premenopausal and 16 postmenopausal) women with newly diagnosed CS (18 with pituitary adenoma, 10 with adrenal tumor and 1 with ectopic) was measured by dual x-ray absorptiometry (DEXA) and was compared with BMD of 29 age, body mass index (BMI)- and oestrogen status matched healthy controls. Furthermore, in 18 (9 premenopausal and 9 postmenopausal) of the above patients (14 with pituitary adenoma, 5 with adrenal tumor and 1 with ectopic) broadband ultrasound attenuation (BUA) by quantitative ultrasound (QUS) of the heel was estimated and 18 age-, BMI- and oestrogen status matched healthy women served as controls. In all the patients serum BGP and UFC were measured at the time of diagnosis of CS. RESULTS: Compared to their matched controls, BMD in the forearm and BUA values in the heel did not differ in the premenopausal women with CS, while in the postmenopausal group BMD in the forearm was decreased (P < 0.05) but not BUA. Apart from a weak negative correlation between serum BGP and BMD in the ultradistal site of the forearm in premenopausal women (P = 0.05), serum BGP and UFC did not show significant correlation with BMD or BUA. CONCLUSIONS: BMD in the forearm is reduced only in postmenopausal women with newly diagnosed endogenous CS, while BUA in the heel is unaffected in both pre- and postmenopausal patients. Moreover, serum BGP and UFC do not seem to be relevant markers for assessing bone loss in the peripheral skeleton at the time of diagnosis of hypercortisolemia.     

A longitudinal analysis of premenopausal bone loss in healthy women and women with hyperprolactinemia.

In this report we describe longitudinal measurements of forearm and spinal bone mineral in healthy women and women with hyperprolactinemia. One hundred and ten women underwent yearly assessment of forearm and spinal bone mineral by single photon absorptiometry and computed tomography for an average of 4.7 yr. At entry into the study, women with hyperprolactinemic amenorrhea had 21% lower spinal bone mineral and 2.5% lower forearm bone mineral than healthy premenopausal women. Despite decreased estradiol levels (31 +/- 23 pmol/L), spinal bone in women with hyperprolactinemic amenorrhea did not change over time (+0.08%/yr; P = 0.89). In contrast, spinal bone in healthy women with regular menses (mean age, 34.6 +/- 6.6 yr) decreased significantly (1.7%/yr; P = 0.01). Cortical bone in the forearm did not change in either group. The hyperprolactinemic subjects had higher body mass index (28 +/- 6 vs. 24 +/- 4 kg/m2) and serum testosterone (0.5 +/- 0.2 vs. 0.39 +/- 0.16 pmol/L) than control subjects, but neither parameter correlated with bone loss. Although 64% of the hyperprolactinemic subjects had serum estradiol levels below 30 pmol/L, there was no correlation between estradiol or duration of amenorrhea and bone loss. Women with normal PRL levels and regular menses 3-9 yr after treatment of hyperprolactinemia had significantly lower spinal bone mineral (147 +/- 28 mg/mL) than healthy premenopausal women (169 +/- 29 mg/mL) and showed no change in spinal bone (+0.3%/yr; P = 0.67) over 5 yr. Despite significant hypoestrogenemia, women with hyperprolactinemic amenorrhea did not evidence a rapid decline in spinal bone. Restoration of gonadal function was not associated with normalization of bone mineral. The bone loss that accompanies hyperprolactinemia is not comparable to that which occurs after oophorectomy or menopause. These findings raise important questions about the importance of osteopenia as an indication for treatment of hyperprolactinemic amenorrhea.     

The effect of a gonadotropin-releasing hormone agonist analog (nafarelin) on bone metabolism

The effect on bone metabolism of an agonist analog of GnRH, nafarelin, was studied in 16 premenopausal women, who received 200 micrograms nafarelin/day for 6 months, and 9 premenopausal women, who received 400 micrograms nafarelin/day for 6 months, followed by a 6-month follow-up period. Bone mineral content in the forearm (measured by single photon absorptiometry) and in the spine (measured by dual photon absorptiometry) significantly decreased after 6 months of treatment with 400 micrograms nafarelin, but 6 months after termination of treatment all bone mineral measurements had returned to pretreatment levels. The bone mineral measurements in the 200 micrograms group did not change throughout the study. In both treatment groups the biochemical estimates of bone turnover increased significantly to postmenopausal levels. Withdrawal of treatment resulted in an abrupt decrease in the bone resorption parameters (fasting urinary hydroxyproline to creatinine and calcium to creatinine excretion ratios and serum phosphate), whereas there was a protracted fall in the bone formation parameters (plasma bone Gla protein and serum alkaline phosphatase) 6 months after termination of treatment. Our findings demonstrate that nafarelin in both doses increased biochemical indices of bone turnover, that 400 micrograms/day nafarelin resulted in a significant decrease in bone mineral content, and that these effects were reversible.     

17 Beta-estradiol and continuous norethisterone: a unique treatment for established osteoporosis in elderly women

Forty women aged 64.7 +/- 5.1 yr with established postmenopausal osteoporosis were blindly allocated to 1 yr's treatment with either continuous combined estrogen/progestogen therapy (2 mg estradiol + 1 mg norethisterone acetate + 500 mg calcium daily) or placebo + 500 mg calcium daily. In the group treated with hormones bone mineral density in the spine (dual photon absorptiometry) and bone mineral content in the ultradistal forearm (single photon absorptiometry) increased highly significantly by 8-10% during the 1 yr of treatment. Bone mineral content in the mid-shaft of the forearm (single photon absorptiometry) and the total body bone mineral (dual photon absorptiometry) increased by 3-5% when compared to that in the placebo group, which showed virtually unchanged values at all measurement sites. Seven of the women treated with hormones were examined after a further year of treatment. BMC increased by another 3-6%, reaching a 12% increase in bone mineral density in the spine after 2 yr of treatment. Biochemical estimates of bone resorption (fasting urinary calcium and hydroxyproline) and bone formation (serum alkaline phosphatase and plasma osteocalcin), decreased significantly (P less than 0.001) in the group treated with hormones, but remained unchanged in the placebo group. The reduction in indices of bone resorption was more pronounced than that in bone formation after one year, indicating a positive bone balance. No further changes were seen in these bone turnover parameters during the second year of treatment. In the group treated with hormones, serum levels of triglycerides, total cholesterol, and low density lipoprotein cholesterol decreased by about 12% (P less than 0.05-P less than 0.01), whereas high density lipoprotein cholesterol decreased by about 8% (P less than 0.001). The high density lipoprotein cholesterol/low density lipoprotein cholesterol ratio was unchanged. The hormone treatment did not produce any major side effects, and only minor bleedings were experienced by a few women. The present study demonstrates that treatment with female sex hormones in this particular combination is a realistic approach to the treatment of women with established postmenopausal osteoporosis.     

Radial and vertebral bone density in white and black women: evidence for racial differences in premenopausal bone homeostasis

The reasons for a different incidence of osteoporotic fractures in white and black women are unknown. Previous racial comparisons of bone mass have been limited by racial differences in body weight and socioeconomic, health, and nutritional status. This cross-sectional study examined bone density in 105 black and 114 white healthy nonobese women, 24-65 yr old, using dual photon absorptiometry of the lumbar spine and single photon absorptiometry of the distal radius. Bone density at both sites was higher in blacks at all ages than in whites. When adjusted for age and body mass index, mean bone density was 6.5% higher in blacks at both spine and radius (P less than 0.0001). The cross-sectional rate of decline of vertebral bone density was similar between races; however, radial density increased 3.8%/decade (P = 0.03) in premenopausal blacks under age 46 yr, while it declined 3.2%/decade (P = 0.09) in premenopausal whites. The racial difference in slopes in these premenopausal women is significant (P = 0.002). These findings suggest that attainment of higher peak bone mass and delayed onset of bone loss contribute to the lower incidence of osteoporotic fractures in black women.     

Bone mineral status in growth hormone-deficient males with isolated and multiple pituitary deficiencies of childhood onset.

In order to determine whether growth hormone (GH) deficiency of childhood onset affects the adult bone mineral status, we assessed bone mineral content (BMC) by photon absorptiometry in 30 full-grown GH-deficient men (8 with isolated GH deficiency and 22 with multiple pituitary deficiencies; 28 previously treated with GH) and in 30 male controls matched for age (within 4 yr) and height (within 10 cm). Forearm BMC was measured by single photon absorptiometry just proximally of the distal one third of the nondominant forearm (PBMC-2 in arbitrary units and PBMC/bone width (BW) after normalization for bone width) and at a more distal site, close to the carpal joint (DBMC-2 and DBMC/BW). Lumbar BMC was measured by dual photon absorptiometry and reported as total BMC for L2-L4 (LBMC in g) and after normalization for projected area (LBMD in g/cm2). The patients had a significantly lower BMC, both at the forearm (P less than 0.0001) and at the lumbar spine (P less than 0.005): 35.7 +/- 1.0 vs. 50.0 +/- 1.6 and 36.9 +/- 1.2 vs. 52.8 +/- 1.9 (mean +/- SEM) for PBMC-2 and DBMC-2 in patients and controls, respectively; 1.36 +/- 0.03 vs. 1.70 +/- 0.04 and 1.07 +/- 0.03 vs. 1.35 +/- 0.04 for PBMC/BW and DBMC/BW; 34.00 +/- 1.08 vs. 42.02 +/- 1.27 g for LBMC and 0.886 +/- 0.016 vs. 0.976 +/- 0.018 g/cm2 for LBMD. Both the patients with isolated GH deficiency and the patients with multiple pituitary deficiencies were osteopenic when compared to their respective controls (P less than 0.01 to P less than 0.0001 for the patients with multiple deficiencies; statistical significance reached for PBMC-2, DBMC-2, and DBMC/BW only, P less than 0.05, in the small group of patients with isolated GH deficiency). For the patients (n = 19) who had at least three serial measurements over a period of 6 to 28 months, no decrease in BMC was detected. Our findings indicate that men with GH deficiency of childhood onset present with a low adult bone mass, despite prior GH substitution in most of these subjects. The observations of a more pronounced bone mineral deficit at the forearm (20-30% lower mean values, depending on the type of measurements) than at the lumbar spine (9-19%) and the findings of osteopenia in both the patients with isolated GH deficiency and multiple pituitary deficiencies, support the view that GH deficiency per se is responsible for part of the observed deficit.(ABSTRACT TRUNCATED AT 400 WORDS)     

Relationship between local and total bone mineral content after gastric surgery

We compared the total body bone mineral mass (TBBM), assessed by the dual-photon technique, with the local bone mineral mass (BMC), measured by single-photon absorptiometry, in 27 ulcus patients treated by either gastric resection or parietal cell vagotomy. Except for raised concentrations of serum alkaline phosphatase in the Billroth I resection group, the biochemical findings and the measurements of bone mass (local and total) were normal. A highly significant correlation between local and total body bone mineral mass was found in both patients (r = 0.84) and controls (r = 0.91). Since the relationship between these two measurements is identical in the patient population and in the age-matched control group, it is concluded that the local BMC may be useful to estimate total bone mass after gastric surgery.     

以生物电阻法检测的身体组成成分与女性骨量的关系

目的 探讨体内的体脂和非体脂对绝经前和绝经后妇女骨密度(BMD)的作用。方法 282例绝经前和205例绝经后妇女参加本研究,用双能X线骨密度仪测定腰椎和股骨颈BMD,用生物电阻法测定体脂和非体脂,同时测量身高、体重、腰围、臀围,并计算体重指数(BMI)和腰臀围比(WHR)。结果 体脂和非体脂与绝经前、绝经后妇女腰椎和股骨颈BMD均呈显著正相关(P＜0．01),多元逐步回归分析显示,在绝经前妇女中,非体脂和年龄是腰椎BMD的独立影响因素(R^2=0．077,P=0．000),非体脂、年龄和BMI是影响股骨颈BMD的决定因素(R^2=0．130,P=0．000),在绝经后妇女中,体脂和年龄是影响腰椎和股骨颈BMD的决定因素(R^2分别为0．153和0．184,P=0．000)。结论 体脂和非体脂对绝经前和绝经后妇女BMD的作用不同,非体脂是决定绝经前妇女骨量的重要因素,而体脂是影响绝经后妇女骨量的重要因素。     

Lean mass and physical activity as predictors of bone mineral density in 16–20-year old women

OBJECTIVE: The aim of the study was to quantify the inter-relationship between bone mineral density and physical activity, muscle strength, and body mass composition in a group of healthy 16-20-year-old women. DESIGN: A cross-sectional study. SETTING: Reykjavik area. SUBJECTS: Two-hundred and fifty-four Icelandic Caucasian women aged 16, 18 and 20 years, randomly selected from the registry of Reykjavik. MAIN OUTCOME MEASURES: Bone mineral content (BMC) and density (BMD) in lumbar spine, hip, distal forearm and total skeleton and lean mass and fat mass were measured with dual energy X-ray absorptiometry (DEXA) and compared with grip strength measured with a dynamometer and physical activity as assessed by a questionnaire. RESULTS: The lean mass had the strongest correlation with BMC and BMD, stronger than weight, height and fat mass, both in univariate analysis (r = 0.41-0.77; P<0.001) and in linear regression analysis. The total skeletal BMD was logarithmically higher by hours of exercise per week (P<0.001)). About 30% of variability in total skeletal BMD in this age group can be predicted by lean mass and physical exercise. CONCLUSIONS: Modifiable factors, such as exercise and adequate muscle seem to be significant predictors of the attainment of peak bone mass in women.