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Diane Krueger

Publications and source records attributed to Diane Krueger.

14 recordsLinked to original sources
PubMed2006

Calcium supplement ingestion may alter lumbar spine bone mineral density measurement.

Densitometry centers commonly request patients abstain from ingesting calcium supplements prior to dual-energy X-ray absorptiometry (DXA) examination to avoid interference with bone mineral density (BMD) measurement. However, it is not clear that this practice is necessary. This study assessed the impact of recent calcium supplement intake on lumbar spine BMD measurement. The phase 1 experiment demonstrated BMD differences when placing a supplement over various areas of two encapsulated phantoms. To determine whether these results were clinically relevant, the phase 2 study enrolled 36 subjects who received spine scans before and after random assignment to ingest one Citracal, OsCal or People's Choice tablet providing 315, 500, and 600 mg of elemental calcium, respectively. The phase 3 study evaluated 15 subjects that had three spine scans with repositioning between to establish BMD precision, and then ingested a calcium carbonate tablet. Post-dosing scans were performed 15 and 30 minutes after tablet ingestion. The difference in L1-L4 BMD on subsequent scans was compared with the study derived least significant change (LSC) of 0.028 g/cm(2). In phase 2, L1-L4 BMD changes outside the LSC occurred in 36% of subjects with 47% having visualized tablets. Similarly, 33% of the phase 3 subjects demonstrated changes outside the LSC after calcium ingestion and 53% of the subjects in phase 3 had tablets visualized. Visualization of calcium tablets was not associated with BMD changes. In conclusion, calcium tablet intake may affect measured L1-L4 BMD within 30 minutes of ingestion. As such, it is appropriate to request patients abstain from calcium tablet ingestion prior to a spine DXA examination.

Absorptiometry, Photon↗
PubMed2005

Combination therapy for osteoporosis: considerations and controversy.

Combination therapy, the simultaneous use of two pharmaceutical agents with the goal being reduction of fracture risk, is an area of substantial clinical interest. This paper summarizes the rationale, existing clinical trials data, and other considerations relevant to combination therapy for osteoporosis. Combinations of antiresorbers (eg, estrogen plus bisphosphonates) produce greater increases in bone mass than either treatment alone. Conversely, combining anabolic agents (parathyroid hormone) with bisphosphonates does not produce additive effects. None of the existing studies are large enough to determine whether combination treatment reduces fracture risk to a greater extent than use of a single agent. However, it is certain that combination treatment will increase cost and likely that it will increase side effects and reduce therapy adherence. Given the absence of demonstrated fracture reduction benefit, increased cost and likely increase in adverse events, combination therapy is not currently recommended.

Alendronate↗
PubMed2005

Combination therapy for osteoporosis: considerations and controversy.

Combination therapy, the simultaneous use of two pharmaceutical agents with the goal being reduction of fracture risk, is an area of substantial clinical interest. This paper summarizes the rationale, existing clinical trials data, and other considerations relevant to combination therapy for osteoporosis. Combinations of antiresorbers (eg, estrogen plus bisphosphonates) produce greater increases in bone mass than either treatment alone. Conversely, combining anabolic agents (parathyroid hormone) with bisphosphonates does not produce additive effects. None of the existing studies are large enough to determine whether combination treatment reduces fracture risk to a greater extent than use of a single agent. However, it is certain that combination treatment will increase cost and likely that it will increase side effects and reduce therapy adherence. Given the absence of demonstrated fracture reduction benefit, increased cost and likely increase in adverse events, combination therapy is not currently recommended.

Bone Resorption↗
PubMed2004

Interobserver reproducibility of criteria for vertebral body exclusion.

UNLABELLED: We studied reproducibility of the ISCD vertebral exclusion criteria among four interpreters. Surprisingly, agreement among interpreters was only moderate, because of differences in threshold for diagnosing focal structural defects and choice of which vertebra among a pair discordant for T-score, area, or BMC to exclude. Our results suggest that reproducibility may be improved by specifically addressing the sources of interobserver disagreement. INTRODUCTION: Although DXA is widely used to measure vertebral BMD, its interpretation is subject to multiple confounders including osteoarthritis, aortic calcification, and scoliosis. In an attempt to standardize interpretation and minimize the impact of artifacts, the International Society for Clinical Densitometry (ISCD) established criteria for vertebral exclusion, including the presence of a focal structural defect (FSD), discrepancy of >1 SD in T-score between adjacent vertebrae, and a lack of increase in BMC or area from L1 to L4. Whereas the efforts of the ISCD represent an important advance in BMD interpretation, the interobserver reproducibility with application of these criteria is unknown. We hypothesized that there would be substantial agreement among four interpreters regarding application of the exclusion criteria and the final lumbar spine T-score. MATERIALS AND METHODS: Each interpreter read a set of 200 lumbar DXA scans obtained on male veterans, applying the ISCD vertebral body exclusion criteria. RESULTS: Surprisingly, agreement among interpreters was only moderate. Differences in interpretation resulted from differing thresholds for recognition of FSD and the choice of excluding the upper or lower vertebral body for the criteria requiring comparison between adjacent vertebrae. CONCLUSIONS: Despite their apparent simplicity, the ISCD vertebral exclusion criteria are difficult to apply consistently. In principle, appropriate refinement of the exclusion criteria may significantly improve interobserver agreement.

Absorptiometry, Photon↗
PubMed2004

Recalculation of the NHANES database SD improves T-score agreement and reduces osteoporosis prevalence.

UNLABELLED: In attempt to improve diagnostic agreement between manufacturers, a recent software update incorporated NHANES III data in GE Lunar densitometers. As a result, the femur neck and trochanter T-scores were lowered, and osteoporosis prevalence was increased. Use of a recalculated young-normal SD for the GE Lunar-adjusted NHANES III database improved diagnostic agreement and is recommended. INTRODUCTION: Use of manufacturer-specific normative databases for T-score derivation leads to discordance in T-score values and differences in diagnostic classification. To address this issue, the International Committee for Standards in Bone Measurement (ICSBM) recommended the NHANES III database for femur T-score derivation. Acquired on Hologic (Hol) instruments, this database requires conversion equations for application to other DXA systems. NHANES III total femur (TF) conversions for GE Lunar (GE) have previously been available, and femoral neck (FN) and trochanter (TR) equations were reported recently. Per the ICSBM recommendation, GE Lunar incorporated these values into their female database. This should produce T-score and diagnostic agreement between Hol and GE instruments; however, this has not been evaluated. MATERIALS AND METHODS: We compared GE femur scans in 115 postmenopausal women using software before and after the NHANES III software update. Subsequently, T-scores derived from femur scans obtained on GE and Hol densitometers were compared in a different group of 89 postmenopausal women. RESULTS: The NHANES III software update had no effect on measured BMD (g/cm2) at any femur region. However, because of changes in values used for T-score calculation (increase in the mean young-normal BMD at the FN and TR and a reduction in SD at the TR), the T-scores were lower (mean, 0.48 and 0.68, respectively) at the FN and TR using post-NHANES III software. Consequently, this update increased femur osteoporosis prevalence in these 115 women from 7.8% to 18.3%. Comparison of GE with Hol total proximal femur T-scores revealed a minimal difference (<0.1) and equal diagnoses of osteoporosis. FN and TR differences were larger, with mean GE T-scores lower than Hol (p < 0.001) by 0.17 and 0.50, respectively, thereby introducing osteoporosis diagnostic disagreement (13 [GE] versus 9 [Hol]). Our evaluation suggested that this disparity resulted from direct application of published NHANES III SDs at the FN and TR. As such, we applied the conversion formulae to the NHANES III published Hologic data and found the FN and TR SDs were greater than assumed by GE. Using our recalculated SD to derive T-scores reduced the mean GE/Hol T-score difference to 0.03 at the FN and 0.32 at the TR and resolved osteoporosis diagnostic disagreement. CONCLUSION: The GE NHANES III software update leads to lower FN and TR T-scores than obtained with Hol or prior GE software. Recalculation of the young-normal SD reduces this difference and is recommended. Clinicians are advised to avoid using the TR for diagnosis or, at a minimum, use caution when making treatment decisions based solely on T-score at this site.

Absorptiometry, Photon↗
PubMed2004

Use of the lowest vertebral body T-score to diagnose lumbar osteoporosis in men: is "cherry picking" appropriate?

In this study, we hypothesized that use of the lowest T-score among four lumbar vertebral bodies would lessen the impact of degenerative arthritis and other artifacts on diagnostic categorization at this site and increase study sensitivity, classifying more men with prior fracture as osteoporotic than the other two methods of lumbar spine analysis. Bone density studies of 533 male veterans measured between January and October 2002 were reviewed to determine diagnostic classification using the L1-L4 average, International Society for Clinical Densitometry (ISCD)-determined, and lowest lumbar vertebral body T-score. We calculated sensitivity and specificity of the three methods of spine analysis, using spine osteoporosis to indicate a positive test and prior fracture as the true indicator of osteoporosis. The lowest lumbar T-score performed with similar sensitivity and specificity to that of the lowest hip or wrist T-score in the ability to classify men with prior fracture as osteoporotic, whereas the average L1-L4 and ISCD-determined T-scores performed with lower sensitivity, but better specificity. In conclusion, this retrospective study suggests that use of the lowest vertebral body T-score among men increases diagnostic sensitivity of lumbar spine bone mass measurement. Prospective studies are needed to determine which of these three methods of lumbar spine analysis best predicts future fragility fracture in men and women.

Absorptiometry, Photon↗
PubMed2003

An overlying fat panniculus affects femur bone mass measurement.

Dual-energy X-ray absorptiometry (DXA) is currently the gold standard technique for osteoporosis diagnosis. However, DXA has limitations, including artifacts, such as degenerative disease or metallic foreign bodies, that may confound bone mineral density (BMD) results. Because fat folds overlying the proximal femur may alter soft-tissue density in a nonuniform manner, this may be a currently unappreciated confounder of proximal femur BMD measurement. This possibility was evaluated in 127 patients (52 women/75 men) referred for routine BMD measurement who were identified as having a fat panniculus overlying their proximal femur scan area. Presence of a fat panniculus within the scan field was confirmed by visual assessment of images obtained utilizing a GE Lunar Expert-XL. Subsequently, these individuals were rescanned while retracting their fat panniculus away from the femur scan area without other repositioning between scans. In 49% of the men, and 56% of the women, either the femoral neck, trochanter, or total femur BMD differed by more than the least significant change at our facility. No pattern was observed to predict whether BMD would increase or decrease upon fat retraction. Subsequently, 30 patients were scanned using the standard and retracted technique twice, with repositioning between scans to establish precision. Retracted and standard precision was similar. In conclusion, an overlying fat panniculus may alter proximal femur BMD measurement, which would be expected to impair the ability to accurately diagnose low bone mass and monitor osteoporosis therapy. When a fat panniculus overlays the proximal femur scan area, its retraction should be part of routine densitometric practice.

Absorptiometry, Photon↗
PubMed2003

Are Wisconsin physicians knowledgeable about male osteoporosis?

It is unknown if recent research defining the relatively frequent occurrence and pathophysiology of male osteoporosis has been conveyed to clinicians. To assess if physicians have incorporated such information, 5646 licensed Wisconsin physicians received a 1-page survey consisting of 14 statements regarding general knowledge, diagnosis, and treatment of osteoporosis in men. Twenty-six percent (1488) responded; 69% (1033) were family physicians or internists, 7% (106) orthopedic surgeons, and 5% (63) endocrinologists or rheumatologists. Of these physicians, 61% to 78% recognized that osteoporosis is not rare in men. Most (68%-97%) agreed that low-trauma fracture or corticosteroid therapy initiation are indications for bone mass measurement. Treating osteoporosis at a T-score of -2.5 was accepted by 79% to 89% of responders. Overall these physicians: (1) recognize osteoporosis as an important disease in men; (2) accept corticosteroid therapy and prior low-trauma fracture as indications for bone mass measurement; and (3) utilize T-scores in treatment decisions. These data suggest that knowledge regarding male osteoporosis has been conveyed to practicing physicians. Evaluation of methods by which physicians will translate this knowledge into action, thereby optimizing patient care, are needed.

Bone Density↗
PubMed2002

Densitometric diagnosis of osteoporosis in men: effect of measurement site and normative database.

Controversy exists regarding which sites to measure, and the appropriate reference database to use, for densitometric diagnosis of osteoporosis in men. While hip and spine bone mineral density (BMD) measurement is routine, spinal osteoarthritis often elevates measured BMD in older men. Additionally, the use of male reference data is standard practice; however, recent reports suggest that a female database may be more appropriate. This study evaluated the effect of sites measured, and normative database utilized, on the densitometric diagnosis of osteoporosis in men. Spine, femur, and ultradistal radial BMD T-scores were determined in 595 male veterans using the GE Lunar male normative database. Subsequently, World Health Organization diagnostic criteria were applied, identifying 282 men with osteoporosis (T-score </= 2.5). The combination of femoral (lowest of neck or total) with the ultradistal radius site was more sensitive (p < 0.0001) for diagnosing osteoporosis than femur plus lumbar spine. When scans from 129 subjects with documented fractures were analyzed using female normative data, fewer (p < 0.0001) met an arbitrary threshold for receiving pharmacologic osteoporosis therapy. In conclusion, BMD measurement at only the spine and hip leads to underdiagnosis of osteoporosis in men. This situation will be exacerbated by utilization of a female normative database; more men with prior fracture may be categorized as not meeting a pharmaceutical intervention threshold.

Absorptiometry, Photon↗
PubMed2002

Osteoporosis in men.

Osteoporosis is often considered a disease of women. However, the lifetime risk of osteoporotic fracture in men is as high as 1 in 4. Furthermore, approximately 30% of hip fractures occur in males. Additionally, morbidity and mortality following osteoporotic fractures appears to be greater in men than women. Thus, it is appropriate that increased attention be paid to this problem in men. Recently, indications for bone mass measurement in men have been published. They include prior low trauma fracture, hypogonadism, and corticosteroid treatment, among others. Additionally, a consensus recommendation that osteoporosis be diagnosed at a T-score of -2.5 or below will soon be published. In men presenting with low bone mass or osteoporotic fractures, secondary causes of bone loss will be found in up to two thirds. The most common secondary causes are corticosteroid use, alcohol abuse, hypogonadism, and idiopathic hypercalciuria. Thus, laboratory evaluation is indicated in osteoporotic men. Finally pharmacologic agents to treat osteoporosis have recently been approved in men. This review highlights current understanding of epidemiology, pathophysiology, diagnosis, and treatment of osteoporosis in men.

Humans↗
PubMedDate not supplied

Addition of right lateral decubitus positioning improves vertebral visualization with VFA in selected patients.

Densitometric vertebral fracture assessment (VFA) allows detection of clinically unappreciated vertebral fracture. However, vertebral visualization using VFA can be suboptimal. In such individuals, alternative spine positioning may enhance visualization. Consistent with this, we observed that reversal of positioning (right lateral decubitus rather than standard left lateral decubitus, subsequently referred to as "reverse" positioning) improved visualization in patients with suboptimal vertebral visualization. This report describes 33 such individuals (i.e., 30 men and 3 women); their mean age and their lowest T-score (L1-L4 spine, proximal femur or 0.3 radius) was 69.9 yr and 2.2, respectively. All images were acquired using a GE Healthcare Lunar Prodigy densitometer (GE Healthcare, Madison, WI). Reverse VFA increased the number of visualized vertebrae in 82% of these patients (27 of 33; p<0.0001). Specifically, only 62% of vertebrae from T4-L5 were visualized using the standard left lateral position. Addition of either full or partial reverse VFA increased (p<0.0001) the number of visualized vertebrae to 83% (384 of 462). In this cohort, reverse positioning allowed detection of 4 additional vertebral fractures, including two in patients without previously identified fractures. We conclude that in selected patients with suboptimal vertebral visualization on VFA, addition of reverse positioning improves visualization and may enhance vertebral fracture detection.

Absorptiometry, Photon↗