Serum bone Gla protein variations during estrogen and calcium prophylaxis of postmenopausal women

Summary We have evaluated serum bone Gla protein (BGP) changes in a double-blind study of early postmenopausal women during treatment with estrogen and calcium. To substantiate the changes in bone turnover, serum alkaline phosphatase, 24-hour urinary calcium, and bone mineral content (BMC) have also been measured. Our results indicate that serum BGP is a valuable measurement of bone metabolism.     

Ovarian hormone status,life-style factors,and markers of bone metabolism in women aged 50 years

Fifty-year-old women (n=519) attending a health examination were divided by their ovarian hormone status into four groups: premenopausal, perimenopausal, postmenopausal without ovarian hormone replacement therapy (HRT), and postmenopausal with HRT. Information on lifestyle factors was obtained with interviews and questionnaires. Bone mineral density at the calcaneus was assessed with single-photon absorptiometry, and several serum and urine markers of bone metabolism were measured. Postmenopausal women without HRT had significantly higher levels of fasting serum alkaline phosphatase, osteocalcin, total and ionized calcium, phosphate, and fasting urinary hydroxyproline than those in the three other study groups. No difference was found in bone mineral density between the premenopausal and postmenopausal groups. Postmenopausal women without HRT showed a marked correlation between serum osteocalcin and urine hydroxyproline. Both markers showed significant correlations with serum calcium, phosphate, and alkaline phosphatase. Multivariate analyses showed a statistically significant association of ovarian hormone status and body mass index with most measured markers of bone metabolism. The association between alcohol consumption and serum osteocalcin was highly significant. Cigarette smoking was associated with levels of serum alkaline phosphatase and total and ionized calcium. A weak association was found between coffee drinking and serum alkaline phosphatase.     

Serum bone gla-protein in osteoporosis treated with 1α-hydroxyvitamin D3 for more than five years

It has been reported that 1,25-dihydroxyvitamin D₃ increases serum bone Gla-protein (BGP) in a short period in osteoporotic patients as well as in normal subjects. There have been, however, no reports on serum BGP in osteoporotic patients under long term treatment with 1α-hydroxyvitamin D₃. We measured serum BGP in 11 osteoporotic women treated with 1α-hydroxyvitamin D₃ and calcium for 5–12 years, 8.4 years on average. Bone mineral density of distal radius was assessed by single photon absorptiometry. Other biochemical parameters such as serum alkaline phosphatase, fasting urinary hydroxyproline/creatinine and calcium/creatinine were also measured. Serum BGP levels were 6.25±0.36ng/ml (mean±S.E.), being all within the normal range (6.2±3.86ng/ml). We found no significant correlation between serum BGP and other biochemical parameters. Significant correlation was found neither between serum BGP and period of treatment nor between serum BGP and bone mineral density. Our result that serum BGP is within the normal range in osteoporotic patients whose bone mineral density has been maintained by long-term treatment suggests the normal bone turnover in these patients.     

A longitudinal study of pre- and postmenopausal changes in calcium metabolism

Longitudinal changes in the serum concentration of calcium, phosphate, alkaline phosphatase, PTH, calcitonin and the renal handling of calcium and phosphate were studied in 19 normal women of the same age before and after the menopause. Significant increase in serum calcium, phosphate and calcitonin and urine calcium/creatinine and TmPO4/GF were shown to precede the premenopause. After cessation of the menstruation, no statistically significant further changes were observed in these variables. Changes in PTH were not observed neither during the premenopausal nor the post-menopausal period. Alkaline phosphatase increased in the postmenopausal period suggesting an increase in bone turn-over.     

Serum bone Gla protein variations during estrogen and calcium prophylaxis of postmenopausal women

We have evaluated serum bone Gla protein (BGP) changes in a double-blind study of early postmenopausal women during treatment with estrogen and calcium. To substantiate the changes in bone turnover, serum alkaline phosphatase, 24-hour urinary calcium, and bone mineral content (BMC) have also been measured. Our results indicate that serum BGP is a valuable measurement of bone metabolism.     

Effects of cyclical etidronate therapy on bone loss in early postmenopausal women who are not undergoing hormonal replacement therapy

This study was carried out to investigate the effectiveness and tolerability of cyclical etidronate therapy in the prevention of bone loss occurring in early postmenopausal women who are not undergoing hormone replacement therapy (HRT). A total of 109 Caucasian women aged 45–60 years were treated with etidronate 400 mg/day or placebo for 14 days followed by calcium supplementation 500 mg/day for 77 days. Ninety-one women completed the 2 years of the study. After 2 years, the estimated difference between the two groups as regards lumbar spine bone mineral density (BMD) was 2.53% (SEM 1.07%;p=0.01); BMD of the hip and wrist were not significantly different between treatment groups. A clear reduction in bone turnover was obtained as evidenced by a significant decrease in serum alkaline phosphatase level and in urinary N-telopeptide/creatinine ratio in the etidronate group; the difference between the two groups was –12%±3.2% for serum alkaline phosphatase level (p=0.019) and –22.9%+13.7% for the urinary N-telopeptide/creatinine ratio (p=0.047). There was no statistically significant difference between the two groups in terms of the serum osteocalcin levels and urinary hydroxyproline/creatinine and calcium/creatinine ratios. Etidronate was generally well tolerated and its adverse event profile was similar to that of placebo. The results of this study indicate that cyclic etidronate therapy can prevent trabecular bone loss, with no deleterious effect on cortical bone, in the first 5 years of menopause and that it has a very high safety margin.     

Effect of etidronate disodium on bone turnover following surgical menopause

Summary A longitudinal study was performed to document the effect of surgical menopause and postmenopausal etidronate disodium therapy on several nonhistomorphometric indices of bone turnover. Twenty healthy, premenopausal women undergoing oophorectomy for nonmalignant conditions were studied preoperatively and at 3 monthly intervals postoperatively. Sequential measurements of serum calcium (Ca), alkaline phosphatase (AP), bone Gla protein (BGP), and urinary calcium and hydroxyproline excretion, expressed as a ratio of urinary creatinine (UCa/Cr and UOHp/Cr, respectively) were obtained. Twenty-four-hour whole body retention of diphosphonate (WBR) and radial bone density were also measured. When a postoperative increase in bone turnover was observed, patients were randomized to receive either 400 mg etidronate disodium daily or placebo for 3 months. Oophorectomy was associated with a significant increase in WBR, Ca, AP, and BGP and an insignificant rise in UCa/Cr. A variable pattern of UOHp/Cr was seen. Patients on placebo maintained these elevated levels of Ca, BGP, and UCa/Cr. WBR and AP continued to rise. Etidronate disodium therapy resulted in a fall towards premenopausal levels in WBR, Ca, and UCa/Cr. AP and BGP were unchanged. Three months after stopping etidronate, BGP fell significantly and the decrease in Ca was maintained; however, WBR and UCa/Cr had returned towards pretreatment values. Bone density measurements did not change significantly. An increase in several of the indices of bone turnover was seen following oophorectomy. Etidronate disodium suppressed this increase, affecting indices of both resorption and formation. This effect on formation may be an unavoidable consequence of normal resorption-formation coupling. The ability of etidronate alone to maintain postmenopausal bone mass has yet to be established. However, the suppressive effect of this diphosphonate on the accelerated bone turnover found after oophorectomy suggests that etidronate may have a potentially useful role as an inhibitor of resorption in a pulsed regimen.     

妊娠妇女性激素、骨密度、骨代谢生化指标的变化及相关性研究

目的：探讨妊振妇女骨密度和骨代谢的变化及其与性激素的关系。方法：随机选取63例健康脑力劳动孕妇和21例健康脑力劳动妇女分别测定骨密度,血清Ca、P、ALP、BGP和E2、P、FSH、LH、PRL以及尿HP/Cr、Ca/Cr比值。结果：孕期骨密度虽有下降但无显变化（P＞0.05),ALP和BGP在晚孕期有显变化（P＜0.05)且此变化与E2成正相关（r=0.61、0.36)。结论：妊娠期骨密度虽无明显变化,但晚孕期骨转换率明显增加且与E2呈正相关。提示可通过测定E2了解孕期骨代谢情况,并及时予以补钙等措施可能有益。     

年龄和雌激素对绝经后妇女骨转换生化指标的影响

目的调查骨转换生化指标的差异,并评估激素和年龄相关因素与绝经前和绝经后妇女生化指标的关系。方法选取在2016年1月至2018年1月期间在我院就诊的女性患者作为研究对象。根据问卷调查,共选出496名健康女性,其中绝经前244例,绝经后女性252例。根据试剂制造商提供的指南评估不同的骨标志物,并且采用化学发光免疫测定法进行激素测定,特别是雌二醇水平评估。结果与绝经前妇女相比,绝经后妇女血清钙水平和雌二醇水平显著降低,而绝经后妇女血清磷和碱性磷酸酶(ALP)水平显著升高(P0.05)。年龄与绝经后骨标志物(ALP和钙)显著相关(P 0.05),而绝经前组无显著相关性。绝经后妇女钙与雌二醇之间呈显著正相关,而ALP与雌二醇之间呈显著负相关。此外,在体质指数和年龄校正偏相关分析中,绝经后妇女雌二醇和骨标志物之间没有显著相关性。结论绝经后女性雌激素水平和骨代谢异常对骨质疏松症的预测有积极的意义。     

Parathyroid hormone and rates of bone formation are raised in perimenopausal rural Gambian women

To investigate rates of bone turnover and calcium homeostasis in Gambian women, we recruited 103 peri- and postmenopausal women, aged 45 to 80+ years and 11 women of reproductive age. Fasting blood was analyzed for plasma osteocalcin, PTH, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D], total- and bone-specific alkaline phosphatase. Plasma and urinary calcium, inorganic phosphate, sodium, potassium, creatinine, and albumin and urine free deoxypyridinoline (Dpd) was also measured. Samples from 20 premenopausal and 31 postmenopausal women from Cambridge, UK were analyzed, using the same methodology for comparison. For the Gambian women, peak calcium excretion occurred at around 50 years of age. For women aged > or =45 years, calcium excretion decreased by 3.0% per year of age (SE 1%; P < 0.005). In this age group, 25(OH)D also decreased with age (P < 0.005). Urinary sodium output, pH, and titratable acid output decreased (all P < 0.05) and total alkaline phosphatase (P < 0.005), osteocalcin (P < 0.005), and PTH (P < 0.05) increased with age. Comparisons were made between the following groups of Gambian and British women: premenopausal, early (age 55-64 years)- and late (age 65+ years)-postmenopausal. Gambian women of all ages were lighter (P < 0.001), shorter (P < 0.01), and had higher plasma bone-specific alkaline phosphatase activity (P < 0.05) and higher concentrations of osteocalcin (P < 0.05), PTH (P < 0.001), 1,25(OH)(2)D (P < 0.001), and 25(OH)D (P < 0.001). There were no consistent differences in calcitonin, while urinary free Dpd outputs were lower in the Gambians (P < 0.001). Plasma calcium, phosphate, and albumin (P < 0.01) were significantly lower. Urinary calcium, phosphate, sodium, and potassium excretion were lower, particularly in the postmenopausal group (P < 0.001). Although Gambian urine pH was more acidic, titratable acid output was lower (P < 0.01). These data show that Gambian women with low dietary calcium intakes and good vitamin D status have low urinary calcium excretion and that menopausal changes in calcium and bone metabolism among Gambian women are similar to those seen in other populations. In addition, they demonstrate that Gambian women of all ages have raised plasma PTH and 1,25(OH)(2)D concentrations and raised markers of osteoblast activity. We postulate that high endogenous PTH concentrations may be beneficial to bone health in Gambian women, removing fatigue damage and improving bone quality.     

Racial differences in pre- and postmenopausal bone homeostasis: association with bone density.

The disparity in fracture incidence and bone mass in women of European (white) and African (black) ancestry is of unknown etiology. To determine if racial differences in bone mass reflected racial differences in the mechanisms of bone turnover underlying bone mineral loss, we measured serum osteocalcin, serum alkaline phosphatase, fasting urinary calcium and hydroxyproline excretion, 24 h urinary excretion of calcium and sodium, and dietary intakes of calcium and vitamin D in 263 healthy pre-, peri-, and postmenopausal white and black women. In addition, radial and spinal bone density were measured cross-sectionally for comparison with biochemical measures of bone turnover. The biochemical parameters thought to reflect bone resorption (fasting urinary calcium and hydroxyproline excretions) were lower in black than in white women throughout the age and menopausal stages studied. The parameters thought to reflect bone formation (alkaline phosphatase and osteocalcin), were similar in the two racial groups among the premenopausal women, but osteocalcin was significantly lower among the peri- and postmenopausal blacks. Cross sectionally measured radial bone density increased with age in premenopausal black women, but it did not change with age in the white premenopausal subjects, a statistically significant difference. In peri- and postmenopausal women radial density declined significantly with years after menopause in both racial groups, but the rate of decline was significantly slower in the black women. Lumbar bone density in premenopausal white and black women did not change with age. After menopause lumbar bone density declined significantly and similarly in both racial groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effects of menopause and estrogen replacement therapy on the renal handling of calcium

Mineral metabolism was studied in 99 premenopausal and 80 postmenopausal women both before and after 9–14 months of treatment with 50 µg/day transdermal estradiol. In estrogen-repleted subjects (premenopausal women and postmenopausal women on estrogen replacement therapy) total serum calcium was significantly lower (0.065 mmol/l;p<0.001) than in those who were estrogen-depleted (untreated postmenopausal women). This difference was smaller but still significant for calculated ultrafiltrable calcium (UFCa: 0.02–0.03 mmol/l;p<0.001). However, ionized calcium (both calculated and measured) was not different in the two groups of women. This finding explains why estrogen repletion does not induce changes in the serum level of intact parathyroid hormone (PTH), despite lower total or ultrafiltrable serum calcium. In a parallel study we have shown that intravenous administration of aminobutane bisphosphonate, a powerful inhibitor of bone resorption, produces similar decreases in serum calcium which were associated with significant increases in intact PTH.Estrogen-depleted women had, on the one hand, significantly higher serum levels of bicarbonate, anion gap, complexed calcium, pH, phosphate and alkaline phosphatase, and higher rates of tubular reabsorption of phosphate and urinary excretion of calcium and hydroxyproline. On the other hand they had lower serum chloride levels and lower rates of tubular reabsorption of calcium.Altogether these findings might indicate that estrogen deficiency decreases renal sensitivity to PTH. This is responsible for the higher serum phosphate and bicarbonate levels, the resulting mild metabolic alkalosis leading to higher serum levels of complexed ultrafiltrable calcium and higher rates of urinary excretion of calcium, but unchanged serum levels of ionized calcium and PTH.     

Effect of age on variables relating to calcium and phosphorus metabolism in women

Lack of adequate data concerning the effect of age on biochemical variables relating to bone and mineral metabolism hampers research on age-related bone loss in women. Furthermore, to detect disease and to monitor therapy, clinical laboratories require reference values derived from an appropriate population sample. Therefore, we determined the age-specific distribution of values for serum concentrations of calcium, inorganic phosphorus, alkaline phosphatase, bone Gla protein, and parathyroid hormone; for creatinine clearance; for fasting urinary calcium:creatinine ratio; and for 24 h urinary excretion of calcium, hydroxyproline, and cyclic AMP in a population-based sample of 301 white women. From this sample, a healthy subgroup of 181 women was identified by medical record review. Age-related effects were seen in all variables except serum calcium and phosphorus. Moreover, substantial differences between the population sample and the healthy subgroup were noted in values for creatinine clearance, serum alkaline phosphatase, and 24 h urinary calcium excretion. These observations may prove useful for assessment of normality in other populations of aging white women.     

Longitudinal Evaluation of Vitamin D Status in Healthy Subjects from Southern Italy: Seasonal and Gender Differences

Vitamin D status is currently considered among the relevant determinants of skeletal integrity. Since vitamin D levels present seasonal variations, we longitudinally studied young healthy men and women in order to investigate the related physiologic modifications of both calcium homeostasis and bone remodeling. Thirty-two men (mean age 39.4 ± 7.8 years) and 58 premenopausal women (aged 36.9 ± 6.4 years) from southern Italy were studied. In all subjects the following parameters were measured both in winter and in summer: serum calcium, phosphorus, creatinine, total alkaline phosphatase activity, 25-hydroxyvitamin D (25OHD), parathyroid hormone (PTH), osteocalcin (BGP), together with urinary calcium (Ca/Cr), total pyridinoline (Pyr/Cr) and deoxypyridinoline (d-Pyr/Cr), corrected for creatinine excretion. In both sexes 25OHD levels were significantly higher in summer, while PTH values were lower, than in winter. The prevalence of hypovitaminosis D, defined by concentrations of 25OHD lower than 30 nmol/l, was 17.8% in winter and 2.2% in summer in the whole sample, while it was 27.8% and 3.4%, respectively, among female subjects. Indeed male subjects did not display hypovitaminosis D, having throughout the year significantly higher calcium and 25OHD levels together with lower PTH values, than the women. Moreover, alkaline phosphatase total activity was more elevated in men both in winter and in summer. In women, during winter, bone remodeling markers levels were higher while urinary calcium levels were lower than in summer. In the whole sample serum 25OHD correlated positively with serum calcium and inversely with PTH. The seasonal percentage variations in PTH were inversely correlated with those of Ca/Cr. Our results show a relatively high prevalence of subclinical vitamin D deficiency among young healthy women from southern Italy. Significant gender-specific differences have been demonstrated in both calcium homeostasis and skeletal remodeling indexes; the seasonal fluctuations in the vitamin D–PTH axis are accompanied by cyclical variations of bone turnover rate, which were more pronounced in women. Received: 11 January 2001 / Accepted: 6 July 2001     

Comparison of the effects of calcium loading with calcium citrate or calcium carbonate on bone turnover in postmenopausal women

Calcium supplementation is known to increase bone mineral density and decrease fractures, but the relative efficacy of different forms of calcium supplementation is not established. We compared the effects of calcium carbonate and calcium citrate on markers of bone resorption in older postmenopausal women in an open-labeled crossover study. Forty women were randomized to receive 1000 mg/day of either calcium citrate or calcium carbonate for 12 weeks, followed by a 2-week washout without calcium supplements and 12 weeks treatment with the alternate calcium supplement. All women received vitamin D (900 IU/day). Thirty-four women (25 Caucasian, nine Hispanic) completed the study. No significant differences in the decrease in parathyroid hormone (PTH) or bone specific alkaline phosphatase or the increase in urinary calcium/creatinine were detected between the two treatments. However, calcium citrate supplementation decreased the collagen cross-link resorption markers, urinary N-telopeptide (–30%), C-telopeptide (–31%), free deoxypyridinoline (19%) and serum N-telopeptide (–8%), compared to no significant change following calcium carbonate supplementation (+2%, +3%, +2% and +2%, respectively; P<0.05). Calcium citrate decreased markers of bone resorption significantly more than calcium carbonate in postmenopausal women, although no differences in their effects in calcium excretion or PTH were detected.     

Prospective trial of ossein-hydroxyapatite compound in surgically induced postmenopausal women

Women with increased bone resorption induced by bilateral oophorectomy 1-5 years previously (of a total of 48 women in the study, 20 were controls, and 28 were the treatment group) were studied during a 3 year follow-up. The ossein-hydroxyapatite compound (OHC) treatment provided 1.6 g calcium, 0.74 g phosphorus and 1.94 g noncollagen peptides a day. Biochemical indices of bone remodeling (urinary hydroxyproline/creatinine and calcium/creatinine ratios, bone alkaline phosphatase isoenzyme in serum and plasma tartrate resistant acid phosphatase) decreased significantly in both treatment and control groups compared with their baseline values. Biochemical indices were significantly lower in the treatment group compared to the controls after the first year, but in only half the patients after three years. By the third year these responders had significantly higher cortical area than controls. In an additional 13 women a transient response to OHC was followed by an accelerated bone loss and a return to the control values of the biochemical indices of bone resorption. In the poor responders an estrogen/progesterone substitution resulted within 6 months in a complete normalization in the biochemical parameters and in no further cortical bone loss. The results confirm a heterogeneous pattern of bone mass loss in menopause and indicate that OHC treatment is of value in preventing cortical bone loss in a portion of at-risk postmenopausal women, provided that the efficacy of the treatment is monitored.     

Is heritability a risk factor for postmenopausal osteoporosis?

We investigated heritability as a risk factor for the development of osteoporosis in two randomly selected populations of postmenopausal women and their premenopausal daughters. We determined the familial resemblance in bone mass at three sites; the distal forearm, lumbar spine, and proximal femur, premenopausally and with increasing maternal postmenopausal age. We also examined the bone mass of daughters in relation to mothers with and without osteoporotic fractures. Peak bone mass among premenopausal siblings was significantly correlated at all sites (r = 0.30-0.42, p less than 0.001). The same levels of resemblance were found between early postmenopausal mothers and premenopausal daughters. There was no significant difference in bone mass at any skeletal site between daughters of women with either peripheral or spinal fractures and daughters of women without fractures. We also examined familial resemblance with four biochemical markers of bone turnover (fasting urinary calcium and hydroxyproline, both corrected for creatinine, serum alkaline phosphatase, and plasma bone Gla protein). A generally significant resemblance were seen in premenopausal siblings (r = 0.25-0.39, hydroxyproline NS), but not between premenopausal daughters and postmenopausal mothers. We conclude that peak bone mass is hereditary in the distal forearm, lumbar spine, and proximal femur, but the mother-daughter resemblance explains only about 16% of the variability in daughters' bone mass. Furthermore, daughters of women with a moderate state of osteoporotic fractures are not substantially at an increased risk of having a low peak bone mass compared to the daughters of women without fractures.     

Is there a role for a random measurement of 24-hour urine calcium excretion and serum total alkaline phosphatase in the determination of fracture risk in osteoporotic postmenopausal women?

Our objective was to explore whether a casual determination of 24-hour urinary calcium excretion and serum total alkaline phosphatase (TAP), in osteoporotic postmenopausal women are independent predictors for osteoporotic fracture. Subjects were 121 women with postmenopausal osteoporosis (mean age 62.8 +/- 9.9) segregated in two study groups based on prevalence of osteoporotic fractures (51 women with prevalent fractures and 70 without fractures), similar in terms of age and BMI. We measured bone mineral density (BMD) by DXA at lumbar spine and femoral neck. Vertebral fracture assessment was done by plain X ray evaluation. Routine blood tests and extensive endocrine evaluation were performed in all patients to exclude secondary causes of osteoporosis. Serum TAP, calcium, phosphate and urinary calcium excretion was measured to evaluate bone metabolism. We did not find any significant differences between groups regarding lumbar T score (-3.1/-2.9 SD), femoral neck T score (-2.2/-1.8 SD), lumbar Z score (-1.5/-1.9 SD) or femoral neck Z score (-1.5/-1.8 SD). Serum TAP was higher in fracture group (211.5 UI) comparing to non-fracture osteoporotic women (208.3 UI) without statistical significance. We were not able to find any significant difference between groups in terms of urinary calcium excretion (9.13/5.4 mEq/24h) or serum total calcium (4.8/4.9 mmol/l). CONCLUSION: in spite of a mean TAP near the upper limit of normal range which could be related to low bone mass, there is no significant relationship to fracture risk in osteoporotic postmenopausal women. Based on our data, a casual measurement of urinary calcium excretion seems irrelevant for BMD independent fracture risk assessment in this clinical setup.     

骨质疏松患者骨碱性磷酸酶、钙、磷代谢变化及与牙槽骨骨密度的相关性

目的探究骨质疏松患者血清钙、磷、骨碱性磷酸酶代谢变化及其与牙槽骨骨密度的相关性,以期通过血生化指标了解牙槽骨的代谢状况。方法 46例患者随机分为2组,观察组(强骨胶囊组)和对照组(阿仑膦酸钠片组)各23例,药物治疗前采集静脉血进行血清钙、磷、骨碱性磷酸酶水平检测,并行锥形束CT检查,测量牙槽骨骨密度,药物治疗后6月时重复以上检测和检查,观察血清钙、磷、骨碱性磷酸酶变化情况,分析以上血生化指标与牙槽骨骨密度的相关关系。结果药物治疗前及药物治疗后6月观察组和对照组血清钙、磷及骨碱性磷酸酶变化组间比较均无统计学意义(P0.05)。药物治疗前及药物治疗后6月观察组和对照组血清钙、磷变化与牙槽骨骨密度无统计学相关性(P0.05)。药物治疗前观察组和对照组BALP与牙槽骨颊(唇)侧皮质骨骨密度变化呈负相关(r=-0.440,P0.05;r=-0.419,P0.05),药物治疗后6月两组BALP与牙槽骨颊(唇)侧皮质骨骨密度亦呈负相关(r=-0.642,P0.05;r=-0.442,P0.05)。结论 (1)血清BALP与牙槽骨颊(唇)侧皮质骨BMD呈统计学负相关;(2)强骨胶囊可用以提高合并牙列缺损或缺失的骨质疏松患者牙槽骨骨密度;(3)血清骨碱性磷酸酶可作为评估合并牙列缺损或缺失的骨质疏松患者牙槽骨颊(唇)侧皮质骨骨密度变化的参考指标。     

Comparison of vitamin D metabolism in early healthy and late osteoporotic postmenopausal women

Summary We studied 20 healthy premenopausal women aged 36.5±4.0 years (mean±1 SD), 123 healthy postmenopausal women aged 50.0±2.4 years, and 103 postmenopausal women aged 65.1±5.6 years with symptomatic osteoporosis (forearm and spinal fracture). Serum levels of vitamin D metabolites [25(OH)D, 24,25(OH)₂D₃, and 1,25(OH)₂D] were compared with (1) bone mass in the forearm (single photon absorptiometry) and in the spine (dual photon absorptiometry); (2) biochemical indices of bone formation (serum alkaline phosphatase, plasma bone Gla protien), and bone resorption (fasting urinary hydroxyproline); and (3) other biochemical estimates of calcium metabolism (serum calcium, serum phosphate, 24-hour urinary calcium, intestinal absorption of calcium). The present study revealed no difference in any of the vitamin D metabolites between the premenopausal women, the healthy postmenopausal women and the osteoporotic women as a group. The concentrations of 1,25(OH)₂D and 25(OH)D were significantly lower in patients with spinal fracture than in those with forearm fracture. In the early postmenopausal women, serum 1,25(OH)₂D was related to forearm bone mass (r=−0.20;P<0.05), intestinal calcium absorption (r=0.18;P<0.05), and 24-hour urinary calcium (r=0.21;P<0.05); serum 25(OH)D was related to spinal bone mass (r=0.23;P<0.01). In the osteoporotic women, serum vitamin D metabolites were not related to bone mass, but 1,25(OH)₂D was related to bone Gla protein (r=0.33;P<0.001), serum phosphate (r=−0.27;P<0.01), and 24-hour urinary calcium (r=0.43;P<0.001). The present study demonstrates that in a population that is apparently not deficient in vitamin D, a disturbance of the vitamin D metabolism is not likely to play a pathogenetic role in early postmenopausal bone loss. Patients with spinal fractures have low levels of vitamin D metabolites, which may aggravate their osteoporosis.