Association Study of Parathyroid Hormone Gene Polymorphism and Bone Mineral Density in Japanese Postmenopausal Women

Association of BST B1 restriction fragment length polymorphism (RFLP) of the parathyroid hormone (PTH) gene with bone mineral density (BMD) was examined in 383 healthy postmenopausal women in Japan who were unrelated. The RFLP was represented as B or b, the capital letter signifying the presence of and the small letter the absence of restriction site for BST B1. The frequency of each genotype—BB, Bb, and bb—was 82.5%, 16.7%, and 0.8%, respectively. When we statistically compared age, years after menopause, body height, and body weight between the BB genotype and the Bb genotype groups, there was no significant difference between the groups. However, the lumbar BMD and the score of BMD adjusted for age and body weight (Z score) were significantly lower in the group of genotype Bb than in the BB: 0.859 ± 0.019 g/cm² versus 0.925 ± 0.011 (mean ± SE, P= 0.01) and −0.412 ± 0.138 versus 0.067 ± 0.082 (mean ± SE, P= 0.01). In addition, the Z score of total body BMD in the Bb genotype group was lower than that in the BB group. Comparison of serum and urinary biochemical bone metabolic markers suggested that the subjects with Bb genotype might be in a relatively higher state of bone turnover than those with BB genotype. These results suggest that the polymorphism in the PTH gene would be a useful genetic marker for lower BMD and the susceptibility for osteoporosis. Received: 19 March 1998 / Accepted: 24 June 1998     

Long-Term Vegetarian Diet and Bone Mineral Density in Postmenopausal Taiwanese Women

This study examined bone density among postmenopausal Buddhist nuns and female religious followers of Buddhism in southern Taiwan and related the measurements to subject characteristics including age, body mass, physical activity, nutrient intake, and vegetarian practice. A total of 258 postmenopausal Taiwanese vegetarian women participated in the study. Lumbar spine and femoral neck bone mineral density (BMD) were measured using dual-photon absorptimetry. BMD measurements were analyzed first as quantitative outcomes in multiple regression analyses and next as indicators of osteopenia status in logistic regression analyses. Among the independent variables examined, age inversely and body mass index positively correlated with both the spine and femoral neck BMD measurements. They were also significant predictors of the osteopenia status. Energy intake from protein was a significant correlate of lumbar spine BMD only. Other nutrients, including calcium and energy intake from nonprotein sources, did not correlate significantly with the two bone density parameters. Long-term practitioners of vegan vegetarian were found to be at a higher risk of exceeding lumbar spine fracture threshold (adjusted odds ratio = 2.48, 95% confidence interval = 1.03–5.96) and of being classified as having osteopenia of the femoral neck (3.94, 1.21–12.82). Identification of effective nutrition supplements may be necessary to improve BMD levels and to reduce the risk of osteoporosis among long-term female vegetarians. Received: 10 May 1996 / Accepted: 9 August 1996     

Resistive Training Maintains Bone Mineral Density in Postmenopausal Women

We examined the effects of a total body resistive training program (RT) on total and regional bone mineral density (BMD) in older women. Twenty-seven healthy postmenopausal women (mean age 62 ± 1 years) participated in a strength training program three times/week for 16 weeks. Strength was assessed before and after training by either one or three repetition maximum (1RM and 3RM) tests. Both upper and lower body strength significantly increased by 36–65% and 32–98%, respectively, after training. There was a small but significant decrease in body weight and body mass index after training (P < 0.05), with no change in the waist-to-hip ratio. BMD, assessed by dual-energy X-ray absorptiometry, did not change over the duration of the training period in the anterioposterior spine (L₂–L₄), femoral neck, Ward's triangle, and greater trochanter. BMD of the total body, lateral spine (B₂–B₄), and the regions of the radius (1/3 radius and ultradistal radius) also did not fall in subsets of these women. Muscular strength of both the leg and chest press were significantly associated with L₂–L₄, femoral neck, Ward's triangle, and greater trochanter BMD (range r = 0.57–0.84, all P < 0.005). Markers of bone turnover, namely, bone-specific alkaline phosphatase, osteocalcin, and urinary aminoterminal cross-linked telopeptide of type I collagen did not change significantly. In conclusion, a resistive training program maintains BMD and improves muscular strength in healthy, older women. This may be important in preventing the negative health outcomes associated with the age-related loss of bone density. Received 5 June 1996 / Accepted: 26 June 1997     

Calcaneus Bone Mineral Density Using Single X-ray Absorptiometry in Japanese Women

Calcaneus bone mineral density (BMD) of 738 Japanese women (605 healthy and 133 with osteoporosis) was measured using single X-ray absorptiometry (SXA). A reference range of calcaneus BMD values for healthy Japanese women was established and the usefulness of this method for screening and diagnosis of osteoporosis was evaluated. There was no significant age change of calcaneus BMD prior to menopause, though values decreased significantly thereafter. BMD loss ratio was 1.7%/year in the 10 years after menopause. The reference range of calcaneus BMD was 410 ± 43 mg/cm², calculated from the mean BMD value of subjects whose ages ranged from 25 to 50 years old. The fracture threshold for the spine was established as 294 mg/cm², which corresponded to −2.67 SD from the average BMD of the young healthy women, and the odds ratio for spine fracture in the subjects with BMD lower than this threshold was 3.52 [95% CI (confidence interval) 1.34–9.26]. The spine fracture group showed statistically lower calcaneus BMD than the nonfracture group when subjects with adjusted age and body size were analyzed. There were no significant differences in the ROC analysis for spine fracture between calcaneus BMD and spine BMD. Therefore, calcaneus BMD is not readily affected by degenerative change or soft tissue, and the annual decrement rate (1.7%/year) can be detected easily and with low precision error (0.8%). These indices may prove useful for the screening and diagnosis of osteoporosis. Received: 16 September 1998 / Accepted: 28 January 1999     

Differences in Bone Resorption after Menopause in Japanese Women with Normal or Low Bone Mineral Density: Quantitation of Urinary Cross-Linked N-Telopeptides

The objective of this study was to examine the value of NTx, a urinary cross-linked N-telopeptides of type I collagen, as a marker of bone resorption. We assessed changes in pre- and postmenopausal bone resorption by evaluating the correlation of NTx with L2–4 bone mineral density (BMD) in a total of 1100 Japanese women, aged 19–80 years [272 premenopausal (45.2 ± 6.2 years) and 828 postmenopausal (59.5 ± 6.2 years)]. Postmenopausal women were divided into three groups based on the range of BMD (normal, osteopenic, and osteoporotic). Within each group, subjects were further segregated according to years since menopause (YSM). NTx values were then evaluated for each group. Our results showed that BMD was significantly decreased (P < 0.05) and NTx was significantly increased (P < 0.01) after menopause in age-matched analysis. Consistent with a previous report, NTx was inversely correlated with BMD for the entire cohort of study subjects (r =−0.299), although NTx correlated better with premenopausal than postmenopausal BMD (r =−0.240 versus r =−0.086). This may have been due to the fact that elevated values of NTx were exhibited over the entire range of BMD present in the postmenopausal women, suggesting that NTx might respond faster to the estrogen withdrawal than BMD. In all postmenopausal women, regardless of the range of BMD, the increase in NTx reached a peak within 5 YSM. After 11 YSM, however, NTx remained elevated in the osteoporotic group but it decreased in the osteopenic group, and showed no significant change in the group of postmenopausal women with normal BMD. These findings suggest that bone resorption is dramatically increased within 5 years after menopause but remains increased only in osteoporotic women. Received: 29 April 1997 / Accepted: 12 August 1997     

Rates of Change in Spinal Bone Density Among Japanese Women

To determine the rates of change in bone mineral density (BMD) at the spine in healthy Japanese women, longitudinal measurements of spinal BMD using dual X-ray absorptiometry were collected from 984 women over 17 years of age (mean age 51.6) at eight medical research centers. They were followed up for 20.9 months on average without any treatment influencing bone and calcium metabolism. Measurements of BMD obtained by two different scanners were converted into standardized BMD (sBMD) values. The multiple linear regression model predicts that spinal sBMD increases up to about 23 years of age: the estimated average rates of increases were 0.13%/year for women aged 20 years. After the age of 23, the sBMD began decreasing: the rates of loss increased by 0.045%/year for each year increase in age among premenopausal women. In perimenopausal women, the rate of loss was 2.1%/year. In postnatural menopausal women, the rates of loss decreased exponentially with increasing years since menopause. The rates of loss increased by 0.04%/year for 1 kg decrease in body weight or by 0.1%/year for 1 kg/m² decrease in body mass index. No significant differences in changes in sBMD were found between scanners and between centers after multiple adjustment. We conclude that the rates of change in spinal sBMD are associated with age in premenopausal women, and with years since menopause and weight or BMI in postmenopausal women. Caution is needed, however, when using data from different densitometers to evaluate rates in bone loss in multicenter trials. Received: 13 March 1997 / Accepted: 27 January 1998     

Bone Mineral Densitometry Substantially Influences Health-Related Behaviors of Postmenopausal Women

Although bone mineral density measurements are helpful in predicting future risk for osteoporotic fractures, there is limited information available on how the results of bone densitometry influence a woman's use of therapeutic alternatives. To assess the role of bone mineral densitometry in influencing postmenopausal women to change health behaviors associated with osteoporosis, we prospectively followed, for an average of 2.9 years, 701 postmenopausal women over 50 years of age referred to an osteoporosis prevention program in a large metropolitan area. Assessments included bone mineral densitometry by dual-energy X-ray absorptiometry (with classification of skeletal health), medical history, use of hormone replacement therapy, calcium intake, caffeine intake, exercise, smoking habits, and fall precaution measures. Women classified at baseline with moderate low bone mass were twice as likely (33%), and women with severe low bone mass more than three times as likely (47%) to start hormone replacement therapy compared with women with a normal result (13%, P < 0.001). This was true regardless of whether they had taken hormone replacement therapy in the past. Below-normal BMD was a strong predictor of a woman's initiation of hormone replacement therapy (OR 4.2; 95% CI 2.7–6.4; P < 0.05) even after adjustment for age, education, history of osteoporosis or fracture, and medical condition related to osteoporosis. Women with moderate or severe low bone mass were also much more likely to start calcium supplements (81–90% versus 67%), increase dietary calcium (71–82% versus 60%), decrease use of caffeine (44–60% versus 34%), start exercising (61–76% versus 52%), and quit smoking (22–24% versus 11%) relative to their behaviors prior to testing (P < 0.01). In conclusion, postmenopausal women report that the results of bone densitometry substantially influence the decision to begin hormone replacement therapy and calcium supplements, increase dietary calcium, decrease caffeine, increase exercise, decrease smoking, and take precautions to prevent falls. More studies are needed to measure the long-term effects of this influence. Received: 19 March 1999 / Accepted: 13 August 1999     

MTHFR Polymorphism and Bone Mineral Density: Meta-Analysis of Published Studies

The C677T (rs1801133) polymorphism of methylenetetrahydrofolate reductase (MTHFR) has been associated with bone status in some studies, but the results have been mixed. In order to have a better understanding of this issue, we performed a meta-analysis of studies about the association of the C677T polymorphism and bone mineral density (BMD). Eight studies analyzed the relationship with spine BMD. When their results were combined, individuals with TT genotype showed a small but significantly reduced BMD compared to those with TC and CC genotypes. The weighted mean difference (WMD) was 18.0 mg/cm² (P = 0.001, 95% confidence interval [CI] 7.1–28.9), without statistical evidence for between-study heterogeneity (P = 0.28, I² = 17%). Six studies analyzed femoral neck BMD. A test for heterogeneity was significant (P = 0.03, I² = 56%). Individuals with TT alleles tended to have somewhat lower BMD, but the difference was not statistically significant. In random effects model, the WMD between the TT and TC/CC genotypes was 6.4 mg/cm² (95% CI –7.8 to 21.2, P = 0.36). Total hip BMD was measured in four studies. They showed a significantly lower BMD in subjects with TT alleles: WMD 19.7 (95% CI 5.3-34.1) mg/cm², P = 0.007, in comparison with TC/CC subjects. When we considered only studies on women, the WMD in BMD between TT and TC/CC genotypes was significant at the spine (22.1 mg/cm², 95% CI 8.6-35.6; P = 0.001) and the femoral neck (15.5 mg/cm², 95% CI 4.3-26.7; P = 0.007). There was no evidence for heterogeneity. The small number of studies did not allow a meaningful sex-stratified analysis of total hip BMD or a separate analysis of male data. In conclusion, the C677T polymorphism of the MTHFR gene is associated with small differences in BMD, at least in women.     

Bone Mineral Density and Biochemical Markers of Bone Turnover in Peri- and Postmenopausal Women

Bone mineral density (BMD) measured by densitometry is the elective parameter for the diagnosis of osteopenia and osteoporosis. Biochemical markers have been proposed as sensitive indicators of high bone turnover and for monitoring response to antiresorptive treatment. We conducted a retrospective study to investigate the values of biochemical markers of bone metabolism with a view to early diagnosis of osteoporosis and monitoring of hormone replacement and calcitonin therapy. The subjects were 415 women, mean age 51 ± 8 years (43–62 years) in peri- and postmenopause, recruited at the Menopause Center of Obstetrics and Gynecology Department of Siena University and divided in five groups. Bone densitometry was performed in all subjects and blood samples were taken for assayed biochemical markers, that is, [osteocalcin (OC), parathyroid hormone (PTH), type 1 procollagen (PICP), and calcitonin (CT)]. Three groups of women were divided into two subgroups: those with normal and those with low BMD (<1 SD). Basal concentrations of PCP1, OC, PTH, and CT were compared in the various groups. Two groups of postmenopausal women with BMD below the normal were treated with estrogen replacement therapy and unmodified eel calcitonin. We evaluated whether some of these biochemical markers of bone turnover could help identify women with low BMD and whether they could be useful for monitoring the results of antiresorptive therapies. Markers of bone formation (PICP and OC) make it possible to distinguish women with high turnover who are at risk for osteoporosis from women with low turnover in menopause. A good correlation was also found between changes in levels of these markers and changes in BMD during treatments, which suggests that the PICP and OC would be useful for monitoring response to antiresorptive therapy. Received: 29 March 1998 / Accepted: 2 November 1999     

Influence of Grip Strength on Metacarpal Bone Mineral Density in Postmenopausal Japanese Women: A Cross-Sectional Study

Most published studies on the role of muscle strength in the maintenance of bone mineral density (BMD) focused on the relationship between specific muscle groups and adjacent bones, mostly in young and premenopausal women. This study examined the influence of grip strength on BMD of the metacarpal index in postmenopausal Japanese women. Subjects included 1168 postmenopausal women aged 40–70 years. BMD measurement was done with computed X-ray densitometry (CXD) by analyzing X-ray films of the right second metacarpal index. Grip strength was measured in both the dominant and nondominant hands using a squeeze dynamometer. Grip strength (r = 0.2474; P= 0.0001) and age (r =−0.5443; P= 0.0001) significantly correlated positively and negatively, respectively, with BMD. Physical activity (r = 0.1318; P= 0.0001) also correlated positively with BMD. Breastfeeding (r =−0.1658; P= 0.0001), however, correlated negatively with BMD. Subjects with a history of regular physical activity had higher grip strengths and BMD, than those with no physical activity. Adjustment for age, physical activity, calcium intake, BMI, breastfeeding, testing site, and menopausal type indicated a significant (P for trend = 0.0013) positive association of grip strength with BMD. Subjects with stronger grip strengths had a decreased risk for low BMD. Received: 24 February 1998 / Accepted: 7 August 1998     

Influence of Weight Gain on Spine Mineral Density in Postmenopausal Women

We studied the relationships between weight variables and spine bone mineral density (BMD) in 183 postmenopausal women aged 34–76 years. There was a significant positive correlation of current body mass index (cBMI) and % of ideal body weight (IBW) with BMD. Moreover, the increase in BMI and % IBW was also positively and significantly associated with a higher age-adjusted lumbar BMD. Weight gain, estimated as the difference between current body weight and past ``ideal' body weight, was associated with significant age-adjusted BMD with a threshold of 17%, and postmenopausal women with a gain of over 17% had significantly higher spine BMD. Received: 21 October 1997 / Accepted: 6 October 1998     

Determinants of Bone Mineral Density and Spinal Fracture Risk in Postmenopausal Japanese Women

The present study analyzed the factors that determine bone mineral density (BMD) and predict spinal fracture risk in postmenopausal Japanese women. Two hundred and five postmenopausal Japanese women aged 48–84 years (mean age 64 years) were enrolled in the cross-sectional study. BMD of the lumbar spine, femoral neck and total body as well as body composition were measured by dual-energy X-ray absorptiometry (DXA). Mid-radial BMD was measured by single-photon absorptiometry. We also determined serum levels of insulin-like growth factor (IGF)-I, IGF binding protein-2, -3 and osteocalcin as well as urinary levels of pyridinoline (Pyr), deoxy-Pyr (D-Pyr) and growth hormone. Multiple regression analysis revealed that lean body mass (LBM) was positively correlated with BMD at all sites. In contrast, femoral neck BMD was highly related to fat mass as well as LBM, although fat mass was not an independent correlate of total body and mid-radial BMD. LBM and urinary D-Pyr were crucial determinants at all sites except the mid-radius in stepwise regression analysis. Fat mass and serum IGF-I were determinants of femoral neck and mid-radial BMD, respectively. In terms of reproductive history, parity affected lumbar BMD. Factors affecting BMD differed according to the site. On the other hand, lumbar BMD as well as serum levels of IGF-I and albumin were selected as predictors of spinal fracture risk in multiple logistic regression analysis. Lumbar BMD, serum IGF-I and LBM were selected in women with lumbar BMD above 0.727 g/cm². In conclusion, the present study indicates that LBM is a more important determinant of BMD than fat mass at any site except the femoral neck. Age, serum IGF-I and urinary D-Pyr were also determinants of BMD, dependent on the regions measured. Lumbar BMD and LBM as well as serum levels of IGF-I and albumin were useful markers which predicted the risk of osteoporotic spinal fractures in postmenopausal Japanese women. Received: 6 June 2000 / Accepted: 11 January 2001     

Bone Mineral Density Is a Predictor of Survival

The purpose of this study was to examine the relationship between bone mineral density (BMD) and survival in both sexes and to compare BMD with other established risk factors such as blood pressure and cholesterol. A population-based prospective study of 1924 individuals (850 men, 1074 women) was performed in G?teborg from 1980 to 1983. Measurements of BMD were obtained in 1468 (76%) of the participants (653 men, 815 women). This selection of individuals generated 10,965 person years, and death was registered for 289 men and 197 women in the 7-year period (2661 days) after bone mineral measurement. Later information on date of death was obtained from the official population register. This information covers 7 years from the time of survey of the last examined participant (in Dec. 1983). At the beginning of the study, BMD was measured in the calcaneus by dual photon absorptiometry (DPA), and blood pressure, serum cholesterol, serum triglycerides, and body mass index (BMI) were also recorded. The study was coordinated with the National Register of Causes of Death and the National Cancer Register. A modified version of the Cox proportional hazards model was used to calculate and determine the age-adjusted relations between nontrauma mortality and BMD. When the various quartiles of BMD were compared prospectively from 70, 75, and 79 years of age with survival figures during the 2661-day follow-up period, the first and the second quartiles with the lowest BMD at entry showed the lowest survival rate in both men (P= 0.01) and women (P= 0.01). A decrease of 1 SD of BMD in a univariate analysis was associated with a 1.39-fold increase in mortality in both men (95% confidence interval 1.25–1.56, P < 0.001) and women (95% confidence interval 1.22–1.58, P < 0.001), and a multivariate analysis demonstrated a relative risk of 1.23 (95% confidence interval 1.10–1.41, P < 0.001) in men and 1.19 (95% confidence interval 1.02 to 1.39, P= 0.019) in women. All relations were adjusted for sex, age, and follow-up. This study indicates that BMD is a predictor of survival, especially for subjects over 70. Bone mineral density was found to be a better predictor of death than blood pressure and cholesterol. This study indicates that, after adjustments have been made for diseases, low bone mass is an independent predictor of mortality and might be a marker of general health or functional aging. Its measurement might therefore be a valuable tool in general health investigations. Received: 26 December 1996 / Accepted: 27 January 1998     

Correlation Between Vitamin D Receptor Genotypes and Bone Mineral Density in Japanese Patients with Osteoporosis

In order to better understand the pathogenesis of osteoporosis, we investigated the correlation between the vitamin D receptor (VDR) genotypes defined by BsmI restriction enzyme, as well as other related factors, and the bone mineral density (BMD) at the lumbar spine in 90 Japanese patients with osteoporosis. The same study was performed in 36 patients with osteoarthrosis of the hip joint and 92 healthy volunteers. The majority of the VDR genotypes were bb, and a few of the population showed either the BB or Bb genotype in all three groups. There was no statistical difference in the frequencies of these VDR genotypes in the three groups. The mean age-matched value of BMD (Z scores) at the lumbar spine in patients with osteoporosis was significantly lower than that in patients with osteoarthrosis or healthy volunteers. The mean Z scores of the healthy volunteers with bb genotype were significantly higher than those with BB genotype, whereas those of the osteoporosis patients with BB genotype were significantly higher than those with Bb genotype. There was no significant difference in the mean Z scores between bb and Bb genotypes in patients with osteoporosis and healthy volunteers. No significant difference was seen in the mean Z scores in patients with osteoarthrosis regardless of genotype. On the other hand, body weight significantly correlated with BMD in patients with osteoporosis by simple- and multiple-regression analysis. These results indicate that the BMD at the lumbar spine in Japanese patients with osteoporosis is affected by body weight, and might be affected partially by the VDR genotypes defined by BsmI. Received: 22 September 1995 / Accepted: 24 September 1996     

Bone Density and Body Composition in Japanese Women

Total body bone mineral content (BMC_TB in g) and density (BMD_TB in g/cm²) and body composition were measured in 1006 healthy Japanese women aged 20–79 years using dual X-ray absorptiometry. Peak BMD_TB was 1.11 ± 0.05 g/cm² in women 20–49 years, and mean BMD_TB was 1.019 g/cm² in the 6th decade, 0.956 g/cm² in the 7th decade, and 0.900 g/cm² in the 8th decade. BMD_TB declined by 0.007 g/cm²/year in women after age 50. This age-related decline in BMD showed a similar pattern to that seen for the lumbar spine and femoral neck, but the actual rate of loss was lower for BMD_TB than for these other measurement sites. There was no significant difference between a eumenorrheic premenopausal group and a group with irregular menses. BMC_TB and BMD_TB were associated with body build, lean tissue mass, and fat mass (r = 0.29 ∼ 0.65 and 0.26 ∼ 0.41, respectively). Bone mass and density decreased significantly in older women of all body builds. Premenopausal Japanese women had a 5% lower BMD_TB than U.S. and European whites, but the difference was several times greater in postmenopausal than in premenopausal women. Received: 1 June 1995 / Accepted: 3 March 1997     

Bone Mineral Density and Androgen Levels in Elderly Males

To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years) the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied. BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related factors must be associated with bone loss in elderly males. Received: 29 April 1997 / Accepted: 9 November 1997     

Bone Mineral Density and Bone Size in Men With Primary Osteoporosis and Vertebral Fractures

The bone mineral density (BMD) at the lumbar spine, proximal femur, and total skeleton was evaluated in 38 men with primary osteoporosis and vertebral fractures. BMD of the patients was significantly reduced over all skeletal areas compared with controls. The Z-score of the lumbar spine (−2.8 ± 0.9) was less than that of the other areas (P < 0.001) except the legs (−2.5 ± 1.1) (p.n.s.) showing that bone loss had a tendency to be greater over the axial skeleton. Vertebral dimensions compared with age-matched controls were as follows: projected L2–L4 area (cm 2): 45.7 ± 5.6 versus 53.7 ± 3.6 (P < 0.001); vertebral width (cm): 4.37 ± 0.44 versus 4.90 ± 0.36 (P < 0.001). Serum biochemical parameters and testosterone levels were similar between osteoporotic and control men. We conclude that men with vertebral osteoporotic fractures have reduced vertebral BMD and vertebral dimensions compared with age-matched controls. Thus, these findings indicate that the achievement of a reduced bone size at the end of the growth period or a failure of periosteal increase during adult life is likely to contribute to the pathogenesis of the vertebral fractures observed in older men. Received: 31 January 1997 / Accepted: 2 July 1997