Dual-emission X-ray Absorptiometry Scans Research Articles

Fenestrated screws in osteoporotic spine—Is there an association between the cement distribution and DEXA scan T score?

Abstract Purpose: Cement distribution in spinal stabilization with fenestrated screws is unpredictable in patients with osteoporosis. The objective of our study was an assessment of cement distribution while using fenestrated screws and to establish an association between cement distribution and the Dual Emission X-ray Absorptiometry (DEXA) scan T scores. Materials and Methods: Osteoporotic patients who underwent spinal stabilization with fenestrated screws by a single surgeon with a minimum follow-up of one year were included. Cement distribution (four zones comprising the vertebral body and the pedicle), a pattern of distribution (concentrated or scattered) and cement leakage were assessed on CT scans. Patients were categorized into two groups based on their DEXA scan T scores to test an association between the pattern of distribution of cement and the scores. Clinical improvement was determined using visual analogue scale and Oswestry disability index scores. Results: A total of 126 screws were analyzed in 20 patients with a mean age of 69 years and a mean follow-up of 18 months. Out of 126 screws, 114 (90.47%) had cement in Zones 1 and 2. In total, 58 screws had a concentrated pattern of distribution of cement, whereas 68 screws had a scattered distribution, and the odds ratio of a scattered pattern of distribution was 6.31:1 if the DEXA scan T score was “below (−)3.0.” Clinical improvement was calculated in percentage of change from the preoperative value (mean % visual analogue scale change = 65.13 ± 7.59 and mean % Oswestry disability index change = 43.14 ± 7.24). Conclusion: The pattern of cement distribution in fenestrated screws relates well with the DEXA scan T scores and their usage should be strongly considered in patients with poorer scores. However, there is no relevant difference between the pattern of distribution and the clinical outcome.

Sugar Sweetened Beverages Consumption in Preadolescent Children: 25-Hydroxy Vitamin D and Bone Mineral Density Affection

Objective: To study the effect of heavy consumption of sugar sweetened beverages on serum 25-hydroxy vitamin D (25OHD) level and bone mineral density (BMD) in preadolescents. Study Design: Case-control. Place and Duration of Study: Outpatient clinic in Children`s hospital, Ain Shams University, between September, 2009 and July, 2010. Methods: A questionnaire to define the frequency of beverage consumption was filled by one thousand children within the age range of 8-12 years. Fifty children were selected from the heavy sugar sweetened beverages consumers and were compared to 50 clinically healthy age and sex matched children who gave no history of more than Original Research Article British Journal of Medicine & Medical Research, 4(6): 1400-1412, 2014 1401 average sugar sweetened beverages intake. Each enrolled case filled a questionnaire that assesses duration of beverage intake, frequency and type as well as milk consumption. Questions concerning symptoms of pain, limitation of movement and fractures were also included. Anthropometric measurements were taken. Serum calcium and phosphorus were measured as well as the circulating 25OHD and dual-emission xray absorptiometry scan assessed their BMD Z-score. Results: Children who heavily consumed the sugar sweetened beverages had significantly lower 25 (OH) vitamin D, and BMD Z-score as compared to the controls (t= 4.05, P<0.001 and t= 3.73, P<0.001, respectively). There was significant negative correlations between duration of beverage intake and both BMD Z-score and 25OHD among heavy sugar sweetened beverage consumers(r=0.38, P=0.01 and r=0.4, P<0.001, respectively). A significant negative correlation was detected between duration of beverage intake and serum calcium among heavy sugar sweetened beverage consumers (r = -0.46 and P<0.001) and significant positive correlation between BMD Zscore and 25OHD among them (r = 0.69 and P<0.001). Conclusion: Sugar sweetened beverages intake is associated with a decrease in 25OHD which contributes to low bone mineralization in preadolescents and the duration of intake is the most determinant factor for this association. Consumption of carbonated beverages had more hazardous effect on 25OHD and BMD than packed fruit juice while milk intake showed an opposite effect. We recommend more awareness programs for preadolescents and their parents whether at school or as a part of national campaigns to boost healthy trends in beverage consumption.

Increased Skeletal Muscle Volume in Women With Familial Partial Lipodystrophy, Dunnigan Variety

Familial partial lipodystrophy, Dunnigan variety (FPLD), an autosomal dominant disorder caused by LMNA mutations, is characterized by fat loss from the extremities. However, it is unclear whether these patients appear muscular because of a lack of subcutaneous fat or have an actual increase in muscle mass. Therefore, we compared muscle mass and volume of selected muscles in women with FPLD and control subjects using dual-emission x-ray absorptiometry (DXA) and magnetic resonance imaging (MRI). Whole-body axial MRI and DXA scans were obtained on 39 women, aged 18 to 65 years, with FPLD and 17 healthy women matched for body mass index and age (group 1). Volumes of muscles in both the thighs, calves, and psoas were calculated from MRI scans and muscle mass in extremities were calculated from DXA. In addition, abdominal MRI and DXA scans were analyzed from 129 healthy, frequency-matched women (group 2). Comparisons between women with FPLD and control subjects were made using ANOVA, adjusting for height, body mass index, and age. Patients with FPLD, compared with control subjects had significantly greater volumes of the thigh muscles, (6358 ± 1491 vs 5198 ± 716 mL, P = .002), calf muscles (3133 ± 713 vs 2397 ± 335 mL; P < .001), and psoas muscles (210 ± 51 vs 175 ± 34 [group 1] and 165 ± 38 mL [group 2], P < .001). Patients with FPLD also had significantly increased arm and leg muscle masses when measured by DXA (P < .001). Insulin sensitivity, assessed by insulin tolerance tests, was negatively correlated to the calf muscle volume. Female patients with FPLD have increased skeletal muscle volume and mass compared with those of normal women.

Specrtum of Post Transplant Bone Disorder

Introduction: With the advent of new developments in the field of transplantation, new challenges have emerged in the management of long-term post transplant complications. Post transplantation bone disease represents one such important complication, because it is observed in a substantial proportion of patients. It results in fractures in 20-40% of recipients solid organ transplant compared to non-transplant patients of similar age. Aims: To study the spectrum of bone disorders in initial post transplant period, factors affecting it like various biochemical parameters, effect of immunosuppression and underlying native kidney disease. Methods: We did a prospective clinical study of 50 randomly selected renal allograft recipients who had undergone renal transplantation at our institute during Jan 2009 to August 2010. At baseline and at month 6 and 12 laboratory parameters and BMD (Bone Mineral Density) were analysed. Results: Of the 50 patients, we had 46 men and 4 women with a mean age of 36.9 .49 patients were haemodialysed and one was dialysed peritonealy. Of the 50 patients 32 patients were on calcineuric inhibitor containing regime. 18 patients were on cyclosporine sparing regime which included either mycophenote mofetil or azathioprine ± sirolimus. No patient was on steroid sparing regime. Cumulative dose of steroids for one year in patients with calcineurine inhibitor (CNI) based regime was 5.6 ± 0.67g and that of non CNI based regime was 6.3± 0.87g. 22% of patients had rejection episode treated with additional steroids and immunosuppression. The number of patients with normal BMD decreased to 24% from 76% after one year. The number of osteoporotic patients increased to 30% from 0% and the number of osteopenic patients increased from 18% to 42% during the same period. Out of 15 osteoporotic patients, despite low BMD their serum calcium was either normal or increased in 80 % of patients. We found that there was no statistically significant variation with regard to mean serum alkaline phosphatase levels in the osteoporotic and non osteoporotic groups. The cumulative dose of steroid was 6.30g for the osteoporotic group and 5.96 g for the non-osteoporotic group. The difference was found to be statistically significant (p =0.04). Of total, 5 patients (10%) had post transplant fractures (all had fracture neck of femur). All diabetic patients were osteoporotic and 37.5% (3 patients) of diabetics had fractures. Of the 2 nondiabetic patients having fracture, 1 had osteopenia and 1 had osteoporosis. Conclusions: Post transplant period requires assessment of bone disorder by Dual-emission X-ray absorptiometry (DEXA) scan and influenced by various pre and post transplant factors. DEXA scan is a sensitive monitoring tool. Significant number of renal transplant recipients shows decline in BMD. Diabetics have higher incidence of osteoporotic bone disease.

The Predictive Accuracy of PRE-BMD FRAX Scoring in Identifying the Need for Treating Osteoporosis in Patients with Coeliac Disease

Purpose: Patients with coeliac disease are at increased risk of osteoporosis. Current guidance recommend the use of Dual-Emission X-ray absorptiometry (DEXA) scans at diagnosis of coeliac disease in order to assess for osteoporosis and guide the need for preventative therapy. The WHO fracture risk assessment web tool can be used with or without bone mineral density (BMD) to calculate a FRAX scores (10-year probability of major osteoporotic fracture and hip fracture). Patients are assigned, based on their pre-BMD FRAX outcome into low, intermediate (requiring BMD measurement) and high (requiring preventative therapy) risk groups in accordance with guidelines from the National Osteoporosis Guidelines Group (NOGG). Our study aimed to assess the accuracy of Pre-BMD FRAX scores in predicting need for preventative therapy in a coeliac cohort. Methods: We conducted a retrospective review of 70 biopsy proven coeliac disease patients who had undergone an index DEXA scan whilst attending follow up at our hospital between 2007 and 2011.Clinical data including demographics, DEXA scans was obtained from case note and electronic patient record review. Information regarding previous history of fractures and history of hip fracture in patient parents was obtained by direct interview. Pre and post-BMD FRAX assessment scores were calculated retrospectively. All coeliac patients were considered to have secondary osteoporosis as a risk factor for FRAX calculation. Pre-BMD FRAX risk status was compared with Post-BMD FRAX outcome to identify patients requiring and not requiring therapy. The study was approved by our Institutional Review Board. Results: Seventy biopsy proven coeliac patients (female 51) with a median age of 54 were analysed. Pre-BMD FRAX risk status (low and intermediate/high risk) had a sensitivity of 82 % (95 % CI 73-91) in correctly identifying 9 out of 11 patients as needing treatment. Specificity was 76% (95 % CI 66-86) identifying 44 out of 58 patients as not needing treatment. The positive predictive value (PPV) was 39% (95 % CI 28-50) with 9 out of 23 patients correctly identified as needing treatment but the negative predictive value was high 96% (95% CI 91-100) as 44 patients out 46 were correctly identified as not needing treatment. Specificity and PPV results were influenced by the intermediate risk Pre-BMD FRAX sub-group of which 12 (75%) required lifestyle advice and 4 (25%) required preventative therapy following post-BMD FRAX assessment. Conclusion: In patients with coeliac disease, pre-BMD FRAX risk status is sensitive as well as specific in predicting need for osteoporosis treatment and can help guide clinical decisions potentially avoiding DEXA scanning if appropriate.

The Accuracy of Pre Bone Mineral Density FRAX Scores in Predicting Need for Treatment in Patients with Inflammatory Bowel Disease at Risk of Osteoporosis

Purpose: Patients with Inflammatory Bowel disease (IBD) are at increased risk of Osteoporosis. Dual-Emission X-ray absorptiometry (DEXA) scans are frequently used to assess for osteoporosis and guide the need for preventative therapy. The WHO fracture risk assessment web tool can be used with or without bone mineral density (BMD) to calculate a FRAX score (10-year probability of major osteoporotic fracture and hip fracture). Patients are assigned, based on their pre-BMD FRAX outcome into low, intermediate (requiring BMD measurement) and high (requiring preventative therapy) risk groups in accordance with guidelines from the National Osteoporosis Guidelines Group (NOGG). Our study aimed to assess the accuracy of Pre-BMD FRAX scores in predicting need for preventative therapy in an IBD cohort. Methods: We conducted a retrospective review of 95 patients who had undergone an index DEXA scan whilst attending IBD clinics at our hospital between 2007 and 2011. Clinical data including demographics, disease characteristics and therapy were obtained from case note and electronic patient record review. Pre and post-BMD FRAX assessment scores were calculated retrospectively. All IBD patients were considered to have secondary osteoporosis as a risk factor for FRAX calculation. Fifteen patients were excluded as they had previously received bisphosphonates. Pre-BMD FRAX risk status was compared with Post-BMD FRAX outcome to identify patients requiring and not requiring therapy. Results: Eighty patients (female 56) with a median age of 53.8 and mean disease duration of 14.1 years were analysed. Fifty-two (65%) patients had Crohn's disease, 27 (34%) patients ulcerative colitis and 1 patient had IBD-type unclassified (IBDU). Pre-BMD FRAX risk status (low and intermediate/high risk) had a sensitivity of 100% (95% CI 87.9-100), in correctly identifying 28 out of 28 patients as needing treatment. Specificity was low at 31% (95% CI 19.9-44.3) identifying only 16 out of 52 patients as not needing treatment. The positive predictive value was low (44%; 95% CI 32.3-55.9) with 28 out of 64 patients correctly identified as needing treatment but the negative predictive value was high (100%; 95% CI 80.6-100) as all 16 patients were correctly identified as not needing treatment. Specificity and PPV results were influenced by the intermediate risk Pre-BMD FRAX sub-group of which 33 (73%) required lifestyle advice and 12 (27%) required preventative therapy following post-BMD FRAX assessment. Conclusion: In IBD patients, pre-BMD FRAX risk status is sensitive at predicting need for osteoporosis treatment and can help guide clinical decision making potentially avoiding DEXA scanning in IBD sub-groups.

PWE-277 Fracture prevalence and vitamin D status in primary biliary cirrhosis: the Leicestershire experience

IntroductionMetabolic bone disease is a recognised complication in Primary Biliary Cirrhosis (PBC) and increases the risk of developing fractures. Although osteoporosis is the major contributor, Vitamin D (25- hydroxy- vitamin-...

PWE-239 The accuracy of pre bone mineral density frax scores in predicting need for treatment in patients with inflammatory bowel disease at risk of osteoporosis

IntroductionPatients with Inflammatory Bowel disease (IBD) are at increased risk of Osteoporosis. Dual-Emission x-ray absorptiometry (DEXA) scans are frequently used to assess for osteoporosis and guide the need for preventative...

How good are BMI charts for monitoring children's attempts at obesity reduction?

IntroductionBody mass index (BMI) is the pragmatic measure to assess children's obesity clinically and BMI charts are widely used for counselling families about children's weight management over time.AimsTo explore the...

Calcium supplements lower bone resorption after renal transplant

Bone loss in renal transplant (RT) patients is a problem that begins during end-stage kidney disease and persists after transplantation. Suppression of parathyroid hormone (PTH) may decrease bone loss and improve fracture rate. A single-group prospective intervention study involving 30 patients was performed at a large RT unit. Investigations included dual-emission X-ray absorptiometry scan, vertebral X-ray, calcium absorption test, 24-h urinary calcium and serum measurements of total and ionized calcium, PTH, C-telopeptide cross-links (CTX), osteocalcin, alkaline phosphatase, 25 hydroxyvitamin D (25[OH]D), and 1,25-dihydroxyvitamin D3. Patients were given 500 mg elemental calcium daily for seven d, and serum measurements were repeated. Two-tailed Wilcoxon rank-sum test showed significant decreases in PTH (p<0.01) and CTX (p<0.01) after calcium load. Dietary calcium, mean calcium absorption, and urinary calcium excretion were below desirable levels. Mean 25 hydroxyvitamin D (25(OH)D) was low, but levels of 1,25-dihydroxyvitamin D3 were normal. Calcium absorption significantly correlated with change in PTH (p<0.001), baseline 25(OH)D (p<0.001), and mycophenolate dose (p=0.024). Calcium malabsorption is prevalent in RT recipients, contributing to bone destruction and compounded by poor dietary intake and low 25(OH)D. Calcium supplementation appears to help overcome this deficiency and acutely suppress PTH. Calcium may be an effective and inexpensive therapy for bone loss in RT recipients.

Pattern of use of DXA scans in men: a cross-sectional, population-based study

Osteoporosis in men is underdiagnosed. The use of dual-emission X-ray absorptiometry (DXA) was evaluated in almost 5,000 men aged 60-74 years. DXA was infrequent, despite the presence of multiple risk factors for osteoporosis and a high FRAX score. There is a need for improved targeting of DXA scans for men at high risk. Clinical and socioeconomic factors associated with bone mass assessment (DXA) in men have seldom been evaluated. This study aimed to evaluate factors associated with the use of DXA in men. Self-report information on prior DXA and osteoporosis risk factors were obtained from the baseline data of a study investigating the health perspectives of men aged 60-75 years. Socioeconomic and comorbidity data were retrieved from national registers. The FRAX algorithm was used to calculate the absolute fracture risk. Regression analysis was used to identify factors significantly associated with previous DXA scan. Of the 4,696 men returning questionnaires (50% response rate), 2.7% had prior DXA but 48% had at least one osteoporosis risk factor. Previous DXA was associated with oral glucocorticoid treatment, secondary osteoporosis, rheumatoid arthritis, fracture after age 50, falls within the previous year, smoking, and higher age. Twenty-one percent of men with prior DXA and 10% of men without prior DXA had greater than 20% risk of a major osteoporotic fracture within the next 10 years. One third of those with previous DXA had none of the FRAX osteoporosis risk factors. When family history of osteoporosis and falls were included as risk factors, 18% with previous DXA had no clinical risk factors for osteoporosis. DXA was infrequent in this group of elderly men, despite the presence of risk factors for osteoporosis. DXA was also used despite a low fracture risk. There is a need for improved targeting of DXA scans for men at high risk.

Moderate Daily Exercise Activates Metabolic Flexibility to Prevent Prenatally Induced Obesity

Obesity and its associated comorbidities are of major worldwide concern. It is now recognized that there are a number of metabolically distinct pathways of obesity development. The present paper investigates the effect of moderate daily exercise on the underlying mechanisms of one such pathway to obesity, through interrogation of metabolic flexibility. Pregnant Wistar rats were either fed chow ad libitum or undernourished throughout pregnancy, generating control or intrauterine growth restricted (IUGR) offspring, respectively. At 250 d of age, dual-emission x-ray absorptiometry scans and plasma analyses showed that moderate daily exercise, in the form of a measured amount of wheel running (56 m/d), prevented the development of obesity consistently observed in nonexercised IUGR offspring. Increased plasma C-peptide and hepatic atypical protein kinase Czeta levels explained increased glucose uptake and increased hepatic glycogen storage in IUGR offspring. Importantly, whereas circulating levels of retinol binding protein 4 were elevated in obese, nonexercised IUGR offspring, indicative of glucose sparing without exercise, retinol binding protein 4 levels were normalized in the exercised IUGR group. These data suggest that IUGR offspring have increased flexibility of energy storage and use and that moderate daily exercise prevents obesity development through activation of distinct pathways of energy use. Thus, despite a predisposition to develop obesity under sedentary conditions, obesity development was prevented in IUGR offspring when exercise was available. These results emphasize the importance of tailored lifestyle changes that activate distinct pathways of metabolic flexibility for obesity prevention.

Diurnal secretion of growth hormone, cortisol, and dehydroepiandrosterone in pre- and perimenopausal women with active rheumatoid arthritis: a pilot case-control study

Rheumatoid arthritis (RA) is associated with neuroendocrine and immunologic dysfunction leading to rheumatoid cachexia. Although excess proinflammatory cytokines can decrease somatotropic axis activity, little is known about the effects of RA on growth hormone/insulin-like growth factor-1 (GH/IGF-I) axis function. We tested the hypothesis that patients with active RA exhibit decreased GH/IGF-I axis activity. To do so, we conducted a pilot case-control study at a clinical research center in 7 pre- and perimenopausal women with active RA and 10 age- and body mass index-matched healthy women. Participants underwent blood sampling every 20 minutes for 24 hours (8 a.m. to 8 a.m.), and sera were assayed for GH, cortisol, and dehydroepiandrosterone (DHEA). Sera obtained after overnight fasting were assayed for IGF-I, IGF-binding protein (IGFBP)-1, IGFBP-3, C-reactive protein (CRP), interleukin-6 (IL-6), glucose, insulin, and lipids. Body composition and bone mineral density were evaluated by DEXA (dual emission x-ray absorptiometry) scans. In patients with RA, mean disease duration was 7.6 ± 6.8 years, and erythrocyte sedimentation rate, CRP, and IL-6 were elevated. GH half-life was shorter than in control subjects (p = 0.0037), with no other significant group differences in GH deconvolution parameters or approximate entropy scores. IGF-I (p = 0.05) and IGFBP-3 (p = 0.058) were lower, whereas IGFBP-1 tended to be higher (p = 0.066), in patients with RA, with nonsignificantly increased 24-hour total GH production rates. There were no significant group differences in cortisol or DHEA secretion. Lean body mass was lower in patients with RA (p = 0.019), particularly in the legs (p = 0.01). Women with active RA exhibit a trend toward GH insensitivity and relatively diminished diurnal cortisol and DHEA secretion for their state of inflammation. Whether these changes contribute to rheumatoid cachexia remains to be determined.NCT00034060.