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In vivo bone mineral studies on volunteers during a 370-day antiorthostatic hypokinesia test.

Bone mineral of spine, femur, tibia, forearm, calcaneus, hand, and foot was studied on nine volunteers by quantitative computed tomography, neutron activation analysis, single and dual photon absorptiometry during and after long-term hypokinesia. Conditions of long-term space flight were simulated using a 370-day antiorthostatic hypokinesia test. It is shown that the highest mineral losses occur in foot bones including calcaneus. Remedial measures undertaken delay the process of osteoporosis development but do not completely exclude it. The results obtained by different methods are often conflicting. Consequently, the accuracy of the in vivo methods for bone mineral determination must be more thoroughly studied.

Absorptiometry, Photon↗

PubMed1994

Bone mineral distribution of the proximal tibia in gonarthrosis assessed in vivo by photon absorption.

Regional bone mineral density (BMD, g/cm2) of the proximal tibia including the subchondral plate was measured in vivo by dual photon absorptiometry (DPA). Twenty-one women and six men with gonarthrosis (GA) were examined. Twenty-four healthy women served as controls for the women. The precision error of the BMD measurements ranged from 1.4-3.7% depending on the region measured. Subchondral BMD correlated significantly to the radiologic stage (P < 0.05). Compared to the controls, BMD of the subchondral plate, BMD of the medial condyle, the medial to lateral distribution ratio of subchondral BMD and the ratio between BMD of the subchondral plate and of the immediately underlying region were significantly increased in patients with predominantly medial GA (P < 0.05-0.0001). The BMD of the lateral condyle was lower in GA patients than in controls (P < 0.05). In patients with unilateral GA, the above-mentioned changes were found in the affected tibia compared to the normal knee in the same individual (P < 0.05). In contrast to any of the patients with varus deformity, the two patients with valgus deformity had higher BMD of the lateral condyle than of the medial. No differences in BMD of the distal forearm or the ultradistal region of the proximal tibia were found between the GA patients and the controls. The study shows that regional bone changes of the proximal tibia in GA can be measured precisely and noninvasively in vivo by DPA.

Absorptiometry, Photon↗

PubMed1996

Osteoporosis in steroid-dependent asthma.

BACKGROUND: Patients on prolonged corticosteroid therapy are at risk of developing osteoporosis. Some patients with severe asthma are difficult to wean off corticosteroids and are therefore at risk of developing bony complications due to steroids. OBJECTIVE: The purpose of this study was to examine the relationship of cumulative steroid dosage and duration of therapy with osteoporosis. METHODS: We obtained bone mineral density studies using dual photon absorptiometry, and radiographs of the lumbar spine of 16 steroid-dependent patients with asthma. Patients with conditions affecting bone metabolism were excluded. RESULTS: We studied 16 male steroid-dependent patients with asthma who received 4 to 41 grams equivalent dose of prednisone over a period of 1 to 15 years. The overall prevalence rate for abnormal age-matched bone mineral density was 50%. Abnormal bone mineral density was more commonly noted in the lumbar spine (38%) than in the femoral neck (19%). The lowest dose of corticosteroid associated with a decrease in bone mineral density was a cumulative steroid dose of 5.6 equivalent grams-prednisone. CONCLUSION: Prolonged corticosteroid therapy can cause significant osteoporosis among male patients with steroid-dependent asthma. Bone loss due to corticosteroid therapy occurs at different rates at different bony sites.

Absorptiometry, Photon↗

PubMed2000

Supralesional and sublesional bone mineral density in spinal cord-injured patients.

This study was performed to evaluate supra- and sublesional bone mineral density (BMD) in spinal cord-injured (SCI) patients after 1 year postinjury, and to correlate the BMD to the neurological level; to correlate the sublesional demineralization to functional parameters (duration postinjury, duration of the initial bedrest); and to assess the role of classic methods of prevention such as walking or standing. Thirty-one SCI patients, all male, were studied vs. 31 controls (age matched). The mean age of the population was 36 years (range 18-60 years). Eleven were tetraplegic and 20 were paraplegic. Twenty-six patients dysplayed a complete motor lesion. The BMD was measured by dual-photon absorptiometry on the lumbar spine and on the femoral neck, and the bone mineral content (BMC) on whole-body scans. Particular attention was paid to the distal femur and proximal tibia upper third. Blood samples and urine samples included phosphocalcic parameters, with determination of urinary hydroxyproline and deoxypyridinoline. SCI patients showed a decrease of sublesional BMD of 41% in comparison with controls. This loss of bone mass is higher at the distal femur (-52%) and proximal tibia (-70%), which are the most common sites of fracture. The degree of demineralization for the lumbar spine, the pelvis, and the lower limbs is independent of the neurological level. The duration of acute posttraumatic immobilization (mean 43.3 days) and the time postinjury increase the loss of bone mass for lower limbs (p = 0.04) and particularly for the proximal tibia (p = 0.02). The study of biomechanical stress (i.e., standing, walking, sitting) does not influence the sublesional BMC. This study underlines the major role of the neurological lesion on the decrease of sublesional BMC in SCI patients and the absence of influence of biomechanical stress.

Absorptiometry, Photon↗

PubMed1992

Measurement of bone mass.

The clinical attraction of being able to measure bone density in a precise and accurate manner is clear. With this information, clinicians can identify osteopenic postmenopausal women, assess the effects of disease on the skeleton, and examine the effect of therapy. Significant advances have been made in the last decade in methodology of bone-mass measurements, leading to a number of safe, precise, and accurate techniques. The field continues to change and, for example, dual photon absorptiometry, which itself was a major advance, has now effectively been superceded by dual energy X-ray absorptiometry. It is predicted that such methodology will continue to find an expanding role and will soon be considered part of routine clinical practice. A brief review of the various methodologies that have commonly been used for bone-mass measurements is presented.

Absorptiometry, Photon↗

PubMed1998

Physical activity and bone mineral density in Italian middle-aged women.

Osteoporosis is a major health issue in post-menopausal women on account of the association between low bone mineral density and fractures. A role of physical activity in the prevention and treatment of low bone mineral density is possible but still unclear. The relationship between low spine bone mineral density measured by means of dual photon absorptiometry at lumbar spines, and levels of past and recent physical activity has been assessed by means of a population-based screening study carried out on 1373 women (age 40-64 years) in the North-East of Italy. Physical activity at work and in leisure time was investigated for three specific periods of life: at age 12, between 15 and 19 years (during bone formative years), and in the recent years prior to the interview (30-39 or 50-59 years). Data were analysed comparing low versus high bone mineral density tertile (i.e., 458 and 461 women, respectively), after controlling for other known contributory factors in the development of osteoporosis. A positive association emerged with leisure time physical activity, with significant trends at age 15-19 (odds ratio (OR) for low versus high tertile of leisure time activity: 1.4, 95% confidence interval (CI): 0.8-2.4) and at most recent age (OR: 1.7, 95% CI: 1.1-2.6). Risk trends with occupational physical activity were less clear and non-statistically significant. The present Southern European cross-sectional study lends further support to the possibility that past and recent physical activity helps increasing bone mineral density in middle-aged women. Although the most beneficial type and intensity level of exercise has yet to be determined, the present results provide further evidence that participation in even moderate exercise programs should be encouraged.

Absorptiometry, Photon↗

PubMed2001

Bone mineral content and bone metabolism in young adults with severe periodontitis.

OBJECTIVES: To clarify in young adults with severe periodontitis (1) whether the bone mineral content (BMC) or density (BMD) in the mandible/other skeletal sites and the systemic bone metabolism differed from normal and (2) whether mandibular/forearm BMC did change during the 5 to 10-year follow-up. MATERIAL AND METHODS: 24 young otherwise normal patients with verified severe periodontitis were included, of which 20 attended the follow-up visit. Mandibular/forearm BMC was measured at both visits by dual-photon absorptiometry, supplemented with femoral neck/lumbar spine BMD measurements at follow-up visit by dual-energy X-ray absorptiometry. Serum alkaline phosphatase/ionized calcium, urinary excretion of pyridinoline/deoxy-pyridinoline were analysed at the follow-up visit. A conventional periodontal examination was performed at both visits. RESULTS: Mandibular BMC was significantly below normal mean BMC at both visits. The mandibular Z-scores were < or = -2.00 in 33.3% (8/24). BMC/BMD in the remaining sites and the values for bone markers did not differ from normal. Mandibular/forearm BMC was stable while a significant aggravation of alveolar bone loss occurred during the trial without change of probing depth. CONCLUSIONS: Severe periodontitis in young adults seems to be a local disorder associated with relatively low BMC in the jaws without systemic alterations of BMC/BMD and bone metabolism.

Absorptiometry, Photon↗

PubMed1991

Total body calcium in patients with inflammatory bowel disease: a longitudinal study.

1. Serial measurements of total body calcium have been made by prompt gamma-neutron activation analysis in 13 patients with inflammatory bowel disease over a mean period of 23 months. Changes in spinal trabecular bone mineral density and radial shaft bone mineral content were also assessed by using quantitative computed tomography and single photon absorptiometry, respectively. 2. The mean annual decreases (95% confidence intervals) were: total body calcium, 7.8% (-12.0 to -3.7%; P less than 0.001); spinal trabecular bone mineral density, 2.5% (-5.0 to +0.1%; 0.05 less than P less than 0.1), radial bone mineral content, 2.1% (-3.4 to -0.8%; P less than 0.01). 3. No significant correlations were found between rates of change of the three variables. However, there were significant positive correlations between the baseline values for total body calcium and radial bone mineral content (r = 0.638, P less than 0.05), spinal bone mineral density and radial bone mineral content (r = 0.854, P less than 0.01), and total body calcium and spinal bone mineral density (r = 0.876, P less than 0.001). 4. These results demonstrate rapid decreases in total body calcium in patients with inflammatory bowel disease which, in conjunction with the significant decrease in radial shaft bone mineral content, indicate increased rates of cortical bone loss. Whilst values for bone mass at different skeletal sites showed positive correlations within individuals, no relationship was found between the rates of change in bone mass at these sites. 5. The rapid bone loss observed in some subjects emphasizes the importance of early detection of osteoporosis by bone densitometry and the need for effective prophylactic measures to be established in this group of patients.

Absorptiometry, Photon↗

PubMed1997

Bone mineralization and turnover in children with congenital neutropenia, and its relationship to treatment with recombinant human granulocyte-colony stimulating factor.

Bone mineral content (BMC) of the radius was measured using single photon absorptiometry (SPA) in nine children with congenital neutropenia. Five had normal values. Two children with severe congenital neutropenia (SCN) had low BMC, and two boys with Schwachman syndrome had biochemistry suggestive of rickets.

Absorptiometry, Photon↗

PubMed1998

Long-term change in the bone mineral density of adults with adult onset growth hormone (GH) deficiency in response to short or long-term GH replacement therapy.

OBJECTIVE: Only two previous studies have assessed the effects of long-term GH replacement therapy on bone mineral density (BMD) in patients with adult onset GH deficiency. To date no study has looked at the long-term impact on BMD after a short course (6-12 months) of GH replacement. In two groups of patients with adult onset GH deficiency we have studied BMD either (a) after 3 years of continuous GH replacement or (b) 2 years after completion of a short course of GH. DESIGN: An open GH therapeutic study in which patients were recruited from a previous double-blind placebo-controlled study. The BMD status of all patients was unknown to the physician and patient at the time of recruitment. PATIENTS: Group A (n = 7, three females) all received GH replacement continuously for 3 years. Group B (n = 8, five females) included six patients who received GH replacement for 6 months and two who received GH replacement for 12 months with BMD being measured at 6-monthly intervals. METHODS: Single photon absorptiometry (SPA) and later single X-ray absorptiometry (SXA) were used to measure forearm cortical BMD. Dual-energy X-ray absorptiometry (DXA) was used to measure lumbar spine, trochanteric, femoral neck and Ward's area BMD. RESULTS: In group A lumbar spine and trochanter BMD had increased significantly from baseline by 3.7% (DXA: median change = 0.045 g/cm2; P = 0.028) and 4.0% (DXA: median change = 0.031 g/cm2; P = 0.046), respectively. There were non-significant decreases in femoral neck (1.9%) (DXA: median change = -0.02 g/cm2; P = 0.39), Ward's area (6.5%) (DXA: median change = -0.06 g/cm2; P = 0.09) and forearm (2.6%) (SPA/SXA: median change = -0.013 g/cm2; P = 0.18). In group B, compared with baseline, only trochanter BMD changed significantly, increasing by 5.9% (DXA: median change = 0.0485 g/cm2; P = 0.049). Lumbar spine (DXA: median change = -0.001 g/cm2) Ward's area (DXA: median change = 0.0135 g/cm2), femoral neck (DXA: median change = -0.005 g/cm2) and forearm cortical (SPA/SXA; median change = -0.01 g/cm2) BMD did not change significantly (P = 0.67, P = 0.57, P = 0.86 and P = 0.31, respectively). Median percentage changes compared with baseline were -0.1%, 1.8%, -0.5% and -2.1%, respectively. From the time of completion of GH therapy however, BMD increased significantly at lumbar spine, (median change = 0.023 g/cm2), Ward's area (median change = 0.03 g/cm2) and trochanter (median change = 0.056 g/cm2) (P = 0.036, P = 0.049 and P = 0.012, respectively) but not at the femoral neck (median change = 0.017 g/cm2; P = 0.31) or forearm (median change = 0 g/cm2; P = 0.75). CONCLUSION: Long-term GH replacement therapy for three years appears to have beneficial effects on bone in patients with adult onset GH deficiency particularly at the lumbar spine and trochanter; the effects on femoral neck and forearm cortical BMD, however, are less impressive. A short course (6-12 months) of GH replacement therapy results in an increase in trochanter BMD several years later, and after an initial decline in BMD whilst on GH replacement, lumbar spine and Ward's area BMD return towards their baseline values. These results emphasize that not all types of bone and skeletal sites respond to GH therapy identically. Furthermore a short course of GH replacement over 6-12 months may result in significant changes in BMD several years later.

Absorptiometry, Photon↗

PubMed1998

Increased biochemical markers of bone formation and resorption in primary hyperparathyroidism with special reference to patients with mild disease.

OBJECTIVES: To evaluate the impact on bone turnover of primary hyperparathyroidism (pHPT) with special reference to patients with mild pHPT, using biochemical markers of bone formation and resorption. DESIGN: A longitudinal study of patients with pHPT before and one year after surgical treatment. SETTING: The Departments of Internal Medicine and Surgery, Lund University Hospital. SUBJECTS: Forty consecutive patients with pHPT. Thirty of these patients had mild pHPT and are reported separately. Data on bone mineral was also compared to a reference population. INTERVENTION: All patients were operated upon and restudied one year later. MAIN OUTCOME MEASURES: Bone resorption and formation was studied by means of the serum concentrations of the telopeptide of the carboxyterminal region of type 1 collagen (ICTP) and of alkaline phosphatase (ALP), osteocalcin and the carboxyterminal propeptide of type 1 procollagen (PICP), respectively. Bone density was measured at the distal radius by single photon absorptiometry (SPA). RESULTS: Bone formation markers consistently decreased after parathyroid surgery: ALP from 3.51 +/- 0.23 to 2.94 +/- 0.21 microkat L(-1) (P < 0.05), osteocalcin from 6.15 +/- 0.53 to 2.89 +/- 0.23 microg L(-1) (P < 0.001) and PICP from 126.4 +/- 10.9 to 96.0 +/- 6.5 microg L(-1) (P < 0.001). In parallel, the ICTP concentration, reflecting bone resorption, decreased from 5.10 +/- 0.54 to 3.94 +/- 0.34 microg L(-1) (P < 0.001). There was not any significant change in distal radius bone mineral 1 one year after surgery. In the subgroup of patients classified as mild pHPT, a significant decrease was noted for osteocalcin, PICP and for ICTP but not for ALP, without significant changes in variables reflecting distal radius bone mineral content. Glomerular filtration rate was inversely correlated to serum levels of intact PTH, ionized calcium, alkaline phosphatase, osteocalcin and ICTP and directly correlated to the 1.25-dihydroxy-vitamin D concentrations. CONCLUSIONS: pHPT is associated with substantial changes in circulating levels of biochemical markers of bone formation and resorption. These findings are also present in patients with mild pHPT. Renal function should be considered in the evaluation of the impact of pHPT on bone turnover.

Absorptiometry, Photon↗

PubMed1997

Bone metabolism following bladder substitution with the ileal urethral Kock reservoir.

OBJECTIVES: To assess bone metabolism following bladder substitution with the ileal Kock reservoir. PATIENTS, SUBJECTS AND METHODS: The investigation comprised two separate studies, one with baseline measurements before and after surgery, and the second after surgery only, of bone mass, made using single-photon absorptiometry and dual-energy X-ray absorptiometry, biochemical variables of bone turnover, plasma analyses and measurements of renal calcium and phosphate excretion. After inclusion, both groups of patients were observed longitudinally for 2 years. The post-surgery study included 25 patients who had undergone bladder substitution (median age 67 years, range 44-75), with a median post-operative follow-up of 1.0 year (range 0.3-3.7), and 16 control subjects (either healthy or with other minor urological complaints; median age 62 years, range 34-80), and the pre-surgery study comprised seven patients who had undergone bladder substitution (median age 57 years, range 42-68). RESULTS: Total body, forearm and spinal bone mineral contents were similar in patients with an ileal bladder substitute measured 1 year after surgery and in control subjects. There were equivalent significant changes in both the patients and control subjects during the 2-year observation period, with a 2-3% decrease in total body and forearm bone mineral content. The values were similar in patients with and without a mild metabolic acidosis. Plasma calcium, phosphate, total alkaline phosphatase, intact parathyroid hormone, vitamin D and osteocalcin were normal in both patients and control subjects. Renal excretion of calcium and phosphate was also similar in patients and in control subjects. CONCLUSIONS: Ileal urethral Kock bladder substitution does not lead to accelerated bone mineral loss in elderly men, despite a mild metabolic acidosis in half of the patients.

Absorptiometry, Photon↗

PubMed2002

The relationship among history of falls, osteoporosis, and fractures in postmenopausal women.

OBJECTIVE: To study the relative contribution of osteoporosis and falls to the occurrence of symptomatic fractures in postmenopausal women. DESIGN: Retrospective survey of current osteoporosis in relation to falls and fractures in the preceding year. SETTING: Patients of general practitioners of the area around a Belgian university. PARTICIPANTS: A total of 2649 consecutive postmenopausal women (mean age, 61y; range, 45-91y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Current bone density measurements (single-photon absorptiometry in the forearm) were analyzed in relation to self-reported incidence of falls and fractures in the preceding year. RESULTS: Osteoporosis was found in 15% of the patients, 19% reported 1 or more falls during the preceding year, and 1.8% had a fracture during the preceding year. The age-adjusted risk for a fracture in the past 12 months for a 1 standard deviation decrease in bone density was 1.9 (95% confidence interval [CI], 1.4-2.5; P<.01). Adjusted risk for age, bone density, and body mass index (BMI) for a fracture in the past 12 months in patients who reported a fall was 6.0 (95% CI, 3.1-11.5; P<.001). Compared with women without osteoporosis and without a fall, women with osteoporosis without a fall had an age- and BMI-adjusted fracture risk of 2.8 (95% CI, 0.6-12.8; P<.10), and women with osteoporosis and a fall had an adjusted-fracture risk of 24.8 (95% CI, 6.9-88.6; P<.0001). CONCLUSIONS: Falls are a major contributing factor to the occurrence of symptomatic fractures in postmenopausal women, independent of and additive to the risk attributable to age and osteoporosis.

Absorptiometry, Photon↗

PubMed1994

[Evidence of fluoride-induced effects on the calcaneus by measurements of broadband ultrasound attenuation (BUA)].

We measured broadband ultrasound attenuation (BUA) of the calcaneus as well as radial (RBD) and spinal bone density (SBD) in normal and osteoporotic females (n = 188) both before treatment and after long-term fluoride therapy. RBD was measured using single photon absorptiometry of the non-dominant distal forearm (SPA) and spinal bone density (SBD) was assessed using quantitative CT (QCT). In untreated osteoporotic patients (n = 62), BUA as well as the other densitometric methods showed significantly lower values (p < 0.05) when compared to age matched controls (n = 75). Females with osteoporosis and long-term treatment with fluoride (n = 51) had both significantly higher BUA values and higher spinal bone density when compared to women with untreated osteoporosis. BUA and SBD were correlated in the entire group (r = 0.5, r < 0.0001) as well as in the subgroups of untreated (r = 0.48, p < 0.001) and fluoride-treated patients with osteoporosis (r = 0.4, p < 0.05). These results suggest that BUA provides further evidence of an osteogenic response to fluoride at peripheral weight-bearing skeletal sites such as the calcaneus.

Absorptiometry, Photon↗

PubMed1993

[The avoidance of early postmenopausal bone substance losses by transdermal estrogen substitution].

The effect of transdermal oestrogen replacement therapy on prevention of osteoporosis was investigated in a controlled randomized study of 38 healthy women (mean age 49.6 [45-54] years) in the early postmenopausal period (< or = 3 years). 19 women (hormone group) continuously used oestrogen patches with a mean daily estradiol delivery of 0.05 mg with addition of medroxyprogesterone acetate, 5 mg orally, for 14 days per month. The other 19 women (calcium group), whose baseline levels were identical, took 500 mg calcium daily. Climacteric symptoms improved significantly in the hormone group, and serum and urinary calcium levels and total serum cholesterol all declined, while the HDL cholesterol levels increased slightly. Bone density was measured by single photon absorptiometry at two points (1/3 and 1/10 of the forearm length from the distal end of the radius). After 6 and 12 months, the values at the proximal site (1/3) had risen in the hormone group by 1.1% and 0.46% and had fallen in the calcium group by 1.96% and 2.42% respectively (both P < 0.05 vs hormone group). At the distal radial site (1/10), the values increased by 2.14% and 5.3% in the same period and fell by 3.59% and 5.67% in the calcium group. The overall difference after 12 months was 11% (P < 0.01). Transdermal oestrogen appears to be as effective as oral oestrogen replacement for prevention of osteoporosis, and should help to prevent vertebral and limb fractures in the elderly.

Absorptiometry, Photon↗

PubMed1992

Osteopenia in men with a history of delayed puberty.

BACKGROUND AND METHODS: The effect of delayed puberty on peak bone mineral density in men is unknown. To determine whether such a delay reduces normal peak bone density and leads to osteopenia during adulthood, we measured radial bone mineral density by single-photon absorptiometry and spinal bone mineral density by dual-energy x-ray absorptiometry in 23 men who had a history of constitutionally delayed puberty and 21 men who underwent normal puberty. Their mean ages were 26 and 24 years, respectively. The groups were matched for other factors known to affect bone mass. RESULTS: The mean (+/- SD) radial bone mineral density was significantly lower in the men with a history of delayed puberty than in the normal men (0.73 +/- 0.07 vs. 0.80 +/- 0.05 g per square centimeter; P less than 0.0002). Spinal bone mineral density was also significantly lower in the men with delayed puberty than in the normal men (1.03 +/- 0.10 vs. 1.13 +/- 0.11 g per square centimeter; P less than 0.003). Radial bone density was at least 1 SD below the mean value for the normal men in 15 of the 23 men with a history of delayed puberty, and spinal bone density was similarly decreased in 10 of the 23. CONCLUSIONS: Adult men with a history of constitutionally delayed puberty have decreased radial and spinal bone mineral density. These findings suggest that the timing of puberty is an important determinant of peak bone density in men. Because the peak bone mineral density achieved during young adulthood is a major determinant of bone density in later life, men in whom puberty was delayed may be at increased risk for osteoporotic fractures when they are older.

Absorptiometry, Photon↗

PubMed1992

Calcium supplementation and increases in bone mineral density in children.

BACKGROUND: Increased dietary intake of calcium during childhood, usually as calcium in milk, is associated with increased bone mass in adulthood; the increase in mass is important in modifying the later risk of fracture. Whether the increase is due to the calcium content of milk, however, is not certain. METHODS: We conducted a three-year, double-blind, placebo-controlled trial of the effect of calcium supplementation (1000 mg of calcium citrate malate per day) on bone mineral density in 70 pairs of identical twins (mean [+/- SD] age, 10 +/- 2 years; range, 6 to 14). In each pair, one twin served as a control for the other; 45 pairs completed the study. Bone mineral density was measured by photon absorptiometry at two sites in the radius (at base line, six months, and one, two, and three years) and at three sites in the hip and in the spine (at base line and three years). RESULTS: The mean daily calcium intake of the twins given placebo was 908 mg, and that of the twins given calcium supplements was 1612 mg (894 mg from the diet and 718 mg from the supplement). Among the 22 twin pairs who were prepubertal throughout the study, the twins given supplements had significantly greater increases in bone mineral density at both radial sites (mean difference in the increase in bone mineral density: midshaft radius, 5.1 percent [95 percent confidence interval, 1.5 to 8.7 percent]; distal radius, 3.8 percent [95 percent confidence interval, 1.4 to 6.2 percent]) and in the lumbar spine (increase, 2.8 percent [95 percent confidence interval, 1.1 to 4.5 percent]) after three years; the differences in the increases at two of three femoral sites approached significance (Ward's triangle in the femoral neck, 2.9 percent; greater trochanter, 3.5 percent). Among the 23 pairs who went through puberty or were postpubertal, the twins given supplements received no benefit. CONCLUSIONS: In prepubertal children whose average dietary intake of calcium approximated the recommended dietary allowance, calcium supplementation increased the rate of increase in bone mineral density. If the gain persists, peak bone density should be increased and the risk of fracture reduced.

Absorptiometry, Photon↗

PubMed1993

Relationship between long-term calcium intake and bone mineral content of children aged from birth to 5 years.

This study evaluated Ca intake in Hong Kong Chinese children and examined the association between long-term Ca intake and bone mineral content (BMC) in children. Longitudinal dietary intake from birth to 5 years was obtained in 128 children (sixty-seven boys, sixty-one girls). Ca intakes were evaluated by dietary history and cross-checked with food frequency and 24 h recall. At age 5 years BMC was determined at the one-third distal radius of the right arm using single-photon absorptiometry. The mean Ca intake of 133 children at 5 years was 546 (SD 325) mg/d. Milk was the chief source of Ca (43.5%). From birth to 5 years, 90% of the children had been taking milk regularly. The mean BMC and bone width (BW) of these children were 0.317 (SD 0.042) g/cm and 0.756 (SD 0.074) cm respectively. BMC was not correlated with current intakes of Ca, energy and protein but was positively correlated with weight (r 0.57), height (r 0.47) and BW (r 0.66). However, cumulative Ca intake throughout the past 5 years showed significant correlation with BMC (r 0.235, P = 0.0133). The significant correlation remained even after weight, height, BW, sex, and cumulative intakes of energy and protein were adjusted in multiple regression analysis (r 0.248, P = 0.0107). Moreover, using principal component analysis, Ca intake during the 2nd year of life had the strongest correlation with BMC at 5 years (r 0.240, P = 0.02). Ca intake of Hong Kong Chinese children was higher than the RDA of the Food and Agriculture Organization/World Health Organization (1962) and achieved 66% of the current US recommendation (National Research Council, 1989). The increased regular milk consumption reflects a significant change in dietary habits of the younger generation. Children with a habitually higher Ca intake throughout the past 5 years, particularly in the 2nd year, were found to have higher BMC.

Absorptiometry, Photon↗