Portable gluten sensors: qualitative assessments by adults and adolescents with coeliac disease.

BACKGROUND: Portable gluten sensors are now commercially available to the public, although there is genuine uncertainty within the medical community over whether they should be used for coeliac disease management. The present study described qualitatively the experience of using a portable gluten sensor for 15 adults and 15 adolescents with coeliac disease participating in a 3-month pilot clinical trial. METHODS: Participants were 30 individuals, aged 13-70 years, with biopsy-confirmed coeliac disease on a gluten-free diet. All received a portable gluten sensor and were randomised to low, medium, and high numbers of single-use capsules. Open-ended questions addressed likes and dislikes using the portable gluten sensor after 3 months. Major themes were identified and described. RESULTS: Participants liked that the portable gluten sensor provided extra assurance to check foods presented as gluten-free, the convenient size and portability, the added sense of control, and overall peace-of-mind. Participants disliked having attention drawn to them when using the sensor and feeling as if they were deterring others from eating. Participants also disliked the physical difficulty associated with using the capsules, questionable accuracy and the inability to test fermented foods. Adults were more enthusiastic about the sensor than adolescents. CONCLUSIONS: Positive and negative experiences may be expected when using commercially available portable gluten sensors to help manage coeliac disease. As future versions of this and other gluten sensors become available, it will be important to investigate the relationship between users' experience with the sensors and long-term outcomes such as mucosal healing and quality of life.

Diminished quality of life among adolescents with coeliac disease using maladaptive eating behaviours to manage a gluten-free diet: a cross-sectional, mixed-methods study.

BACKGROUND: Certain approaches to managing a strict gluten-free diet (GFD) for coeliac disease (CD) may lead to impaired psychosocial well-being, a diminished quality of life (QOL) and disordered eating. The present study aimed to understand adolescents' approaches to managing a GFD and the association with QOL. METHODS: Thirty adolescents with CD (13-17 years old) following the GFD for at least 1 year completed the Celiac Dietary Adherence Test (CDAT) and QOL survey. Their approaches to GFD management were explored using a semi-structured interview, where key themes were developed using an iterative process, and further analysed using a psychosocial rubric to classify management strategies and QOL. CDAT ratings were compared across groups. RESULTS: Gluten-free diet management strategies were classified on a four-point scale. Adaptive eating behaviours were characterised by greater flexibility (versus rigidity), trust (versus avoidance), confidence (versus controlling behaviour) and awareness (versus preoccupation) with respect to maintaining a GFD. Approximately half the sample (53.3%) expressed more maladaptive approaches to maintaining a GFD and those who did so were older with lower CD-Specific Pediatric Quality of Life (CDPQOL) scores, mean subscale differences ranging from 15.0 points for Isolation (t = 2.4, P = 0.03, d.f. = 28) to 23.4 points for Limitations (t = 3.0, P = 0.01, d.f. = 28). CONCLUSIONS: Adolescents with CD who manage a GFD with maladaptive eating behaviours similar to known risk factors for feeding and eating disorders experience diminished QOL. In accordance with CD management recommendations, we recommend ongoing follow-up with gastroenterologists and dietitians and psychosocial support referrals, as needed.

Differentiating Tumor Progression from Pseudoprogression in Patients with Glioblastomas Using Diffusion Tensor Imaging and Dynamic Susceptibility Contrast MRI.

BACKGROUND AND PURPOSE: Early assessment of treatment response is critical in patients with glioblastomas. A combination of DTI and DSC perfusion imaging parameters was evaluated to distinguish glioblastomas with true progression from mixed response and pseudoprogression. MATERIALS AND METHODS: Forty-one patients with glioblastomas exhibiting enhancing lesions within 6 months after completion of chemoradiation therapy were retrospectively studied. All patients underwent surgery after MR imaging and were histologically classified as having true progression (>75% tumor), mixed response (25%-75% tumor), or pseudoprogression (<25% tumor). Mean diffusivity, fractional anisotropy, linear anisotropy coefficient, planar anisotropy coefficient, spheric anisotropy coefficient, and maximum relative cerebral blood volume values were measured from the enhancing tissue. A multivariate logistic regression analysis was used to determine the best model for classification of true progression from mixed response or pseudoprogression. RESULTS: Significantly elevated maximum relative cerebral blood volume, fractional anisotropy, linear anisotropy coefficient, and planar anisotropy coefficient and decreased spheric anisotropy coefficient were observed in true progression compared with pseudoprogression (P < .05). There were also significant differences in maximum relative cerebral blood volume, fractional anisotropy, planar anisotropy coefficient, and spheric anisotropy coefficient measurements between mixed response and true progression groups. The best model to distinguish true progression from non-true progression (pseudoprogression and mixed) consisted of fractional anisotropy, linear anisotropy coefficient, and maximum relative cerebral blood volume, resulting in an area under the curve of 0.905. This model also differentiated true progression from mixed response with an area under the curve of 0.901. A combination of fractional anisotropy and maximum relative cerebral blood volume differentiated pseudoprogression from nonpseudoprogression (true progression and mixed) with an area under the curve of 0.807. CONCLUSIONS: DTI and DSC perfusion imaging can improve accuracy in assessing treatment response and may aid in individualized treatment of patients with glioblastomas.

Diagnostic utility of diffusion tensor imaging in differentiating glioblastomas from brain metastases.

BACKGROUND AND PURPOSE: Differentiation of glioblastomas and solitary brain metastases is an important clinical problem because the treatment strategy can differ significantly. The purpose of this study was to investigate the potential added value of DTI metrics in differentiating glioblastomas from brain metastases. MATERIALS AND METHODS: One hundred twenty-eight patients with glioblastomas and 93 with brain metastases were retrospectively identified. Fractional anisotropy and mean diffusivity values were measured from the enhancing and peritumoral regions of the tumor. Two experienced neuroradiologists independently rated all cases by using conventional MR imaging and DTI. The diagnostic performances of the 2 raters and a DTI-based model were assessed individually and combined. RESULTS: The fractional anisotropy values from the enhancing region of glioblastomas were significantly higher than those of brain metastases (P < .01). There was no difference in mean diffusivity between the 2 tumor types. A classification model based on fractional anisotropy and mean diffusivity from the enhancing regions differentiated glioblastomas from brain metastases with an area under the receiver operating characteristic curve of 0.86, close to those obtained by 2 neuroradiologists using routine clinical images and DTI parameter maps (area under the curve = 0.90 and 0.85). The areas under the curve of the 2 radiologists were further improved to 0.96 and 0.93 by the addition of the DTI classification model. CONCLUSIONS: Classification models based on fractional anisotropy and mean diffusivity from the enhancing regions of the tumor can improve diagnostic performance in differentiating glioblastomas from brain metastases.

Differentiation between glioblastomas, solitary brain metastases, and primary cerebral lymphomas using diffusion tensor and dynamic susceptibility contrast-enhanced MR imaging.

BACKGROUND AND PURPOSE: Glioblastomas, brain metastases, and PCLs may have similar enhancement patterns on MR imaging, making the differential diagnosis difficult or even impossible. The purpose of this study was to determine whether a combination of DTI and DSC can assist in the differentiation of glioblastomas, solitary brain metastases, and PCLs. MATERIALS AND METHODS: Twenty-six glioblastomas, 25 brain metastases, and 16 PCLs were retrospectively identified. DTI metrics, including FA, ADC, CL, CP, CS, and rCBV were measured from the enhancing, immediate peritumoral and distant peritumoral regions. A 2-level decision tree was designed, and a multivariate logistic regression analysis was used at each level to determine the best model for classification. RESULTS: From the enhancing region, significantly elevated FA, CL, and CP and decreased CS values were observed in glioblastomas compared with brain metastases and PCLs (P < .001), whereas ADC, rCBV, and rCBV(max) values of glioblastomas were significantly higher than those of PCLs (P < .01). The best model to distinguish glioblastomas from nonglioblastomas consisted of ADC, CS (or FA) from the enhancing region, and rCBV from the immediate peritumoral region, resulting in AUC = 0.938. The best predictor to differentiate PCLs from brain metastases comprised ADC from the enhancing region and CP from the immediate peritumoral region with AUC = 0.909. CONCLUSIONS: The combination of DTI metrics and rCBV measurement can help in the differentiation of glioblastomas from brain metastases and PCLs.

Pseudopathologic brain parenchymal enhancement due to venous reflux from left-sided injection and brachiocephalic vein narrowing.

In this report, we present a case of a patient with CT angiographic artifacts related to left-sided venous injection resulting in a striking pattern of enhancement simulating vascular abnormalities, which prompted additional diagnostic imaging. To our knowledge, no similar case has been reported in the published literature to date.

Arteriovenous shunt visualization in arteriovenous malformations with arterial spin-labeling MR imaging.

BACKGROUND AND PURPOSE: A reliable quantitative technique for measuring arteriovenous (AV) shunt in vascular malformations is not currently available. Here, we evaluated the hypothesis that continuous arterial spin-labeled (CASL) perfusion MR imaging can be used to detect and measure AV shunt in patients with arteriovenous malformations (AVMs). MATERIALS AND METHODS: CASL perfusion MR imaging was performed in 7 patients with AVMs. Semiquantitative AV shunt estimates were generated based on a thresholding strategy by using signal-intensity difference (DeltaM) images to avoid potential errors in cerebral blood flow (CBF) calculation related to abnormal transit times and nonphysiologic blood-tissue water exchange in and around the AVMs. The potential for measuring CBF in regions distant from and near the AVM was explored, as was the relationship of CBF changes related to the size of the shunt. RESULTS: In all 7 cases, striking increased intensity was seen on CASL perfusion DeltaM maps in the nidus and venous structures draining the AVM. Shunt estimates ranged from 30% to 0.6%. Mean CBF measurements in structures near the AVMs were not significantly different from the contralateral measurements. However, CBF in adjacent ipsilateral white matter increased relative to the contralateral side as the percent shunt increased (P = .02). Cortical gray matter CBF Delta (contralateral-ipsilateral) values demonstrated the same effect, but the correlation was weak and not significant. Thalamic CBF decreased ipsilaterally with increasing percent AV shunt (P = .01), indicating a possible steal effect. Basal ganglia Delta values showed little change in CBF with the size of the AV shunt. CONCLUSION: CASL perfusion MR imaging can demonstrate AV shunting, providing high lesion conspicuity and a novel means for evaluating AVM physiology.

Arterial spin-labeling and MR spectroscopy in the differentiation of gliomas.

BACKGROUND AND PURPOSE: Noninvasive grading of gliomas remains a challenge despite its important role in the prognosis and management of patients with intracranial neoplasms. In this study, we evaluated the ability of cerebral blood flow (CBF)-guided voxel-by-voxel analysis of multivoxel proton MR spectroscopic imaging ((1)H-MRSI) to differentiate low-grade from high-grade gliomas. MATERIALS AND METHODS: A total of 35 patients with primary gliomas (22 high grade and 13 low grade) underwent continuous arterial spin-labeling perfusion-weighted imaging (PWI) and (1)H-MRSI. Different regions of the gliomas were categorized as "hypoperfused," "isoperfused," and "hyperperfused" on the basis of the average CBF obtained from contralateral healthy white matter. (1)H-MRSI indices were computed from these regions and compared between low- and high-grade gliomas. Using a similar approach, we applied a subgroup analysis to differentiate low- from high-grade oligodendrogliomas because they show different physiologic and genetic characteristics. RESULTS: Cho(glioma (G)/white matter (WM)), Glx(G/WM), and Lip+Lac(G)/Cr(WM) were significantly higher in the "hyperperfused" regions of high-grade gliomas compared with low-grade gliomas. Cho(G/WM) and Lip+Lac(G)/Cr(WM) were also significantly higher in the "hyperperfused" regions of high-grade oligodendrogliomas. However, metabolite ratios from the "hypoperfused" or "isoperfused" regions did not exhibit any significant differences between high-grade and low-grade gliomas. CONCLUSION: The results suggest that (1)H-MRSI indices from the "hyperperfused" regions of gliomas, on the basis of PWI, may be helpful in distinguishing high-grade from low-grade gliomas including oligodendrogliomas.

Structural MRI of carotid artery atherosclerotic lesion burden and characterization of hemispheric cerebral blood flow before and after carotid endarterectomy.

Collateral circulation plays a major role in maintaining cerebral blood flow (CBF) in patients with internal carotid artery (ICA) stenosis. CBF can remain normal despite severe ICA stenosis, making the benefit of carotid endarterectomy (CEA) or stenting difficult to assess. Before and after surgery, we assessed CBF supplied through the ipsilateral (stenotic) or contralateral ICA individually with a novel hemisphere-selective arterial spin-labeling (ASL) perfusion MR technique. We further explored the relationship between CBF and ICA obstruction ratio (OR) acquired with a multislice black-blood imaging sequence. For patients with unilateral ICA stenosis (n = 19), conventional bilateral labeling did not reveal interhemispheric differences. With unilateral labeling, CBF in the middle cerebral artery (MCA) territory on the surgical side from the ipsilateral supply (53.7 +/- 3.3 ml/100 g/min) was lower than CBF in the contralateral MCA territory from the contralateral supply (58.5 +/- 2.7 ml/100 g/min), although not statistically significant (p = 0.09). The ipsilateral MCA territory received significant (p = 0.02) contralateral supply (7.0 +/- 2.7 ml/100 g/min), while ipsilateral supply to the contralateral side was not reciprocated. After surgery (n = 11), ipsilateral supply to the MCA territory increased from 57.3 +/- 5.7 to 67.3 +/- 5.4 ml/100 g/min (p = 0.03), and contralateral supply to the ipsilateral MCA territory decreased. The best predictor of increased CBF on the side of surgery was normalized presurgical ipsilateral supply (r(2) = 0.62, p = 0.004). OR was less predictive of change, although the change in normalized contralateral supply was negatively correlated with OR(excess) (=OR(ipsilateral) - OR(contralateral)) (r(2) = 0.58, p = 0.006). The results demonstrate the effect of carotid artery stenosis on blood supply to the cerebral hemispheres, as well as the relative role of collateral pathways before surgery and redistribution of blood flow through these pathways after surgery. Unilateral ASL may better predict hemodynamic surgical outcome (measured by improved perfusion) than ICA OR.

Development of a posterior cerebral artery aneurysm subsequent to occlusion of the contralateral internal carotid artery for giant cavernous aneurysm.

We report a case of a patient who developed a left posterior cerebral artery aneurysm 5 years after balloon occlusion of the right internal carotid artery for a giant cavernous aneurysm. The location of the new aneurysm was outside of the primary collateral pathways to the contralateral, proximally occluded, anterior circulation, illustrating the complexity of hemodynamic factors contributing to the development of intracranial saccular aneurysms. The appearance of an aneurysm in this setting supports the hypothesis that degenerative factors and hemodynamic stresses are important in the etiology of intracranial aneurysms.

Ethnic differences in asthma and associated phenotypes: collaborative study on the genetics of asthma.

BACKGROUND: In the Collaborative Study on the Genetics of Asthma, 314 families with 2584 subjects were characterized for asthma and allergy. OBJECTIVE: The purpose of this investigation was to examine clinical heterogeneity observed in asthma and allergic characteristics among 3 ethnic groups (African American, white, and Hispanic family members). METHODS: Pulmonary function parameters and asthma associated phenotypes were compared among the ethnic groups. RESULTS: In comparison with the other groups, African American sibling pairs had a significantly lower baseline FEV(1) percent of predicted (P =.0001) and a higher rate of skin test reactivity to cockroach allergen (P =.0001); Hispanic sibling pairs had significantly more skin reactivity overall (P =.001); and white sibling pairs had significantly lower total serum IgE (P <.05). In addition, there were significantly more relatives with asthma among the African American families than among the white and the Hispanic families (P =.001). CONCLUSION: Although different environmental backgrounds should be considered, these clinical differences could be due to differences in genetic susceptibility among the ethnic groups, such as those suggested by our previous genome screen.

Knowledge, beliefs, and barriers relevant to colorectal cancer screening in an urban population: a pilot study.

A sample of 115 urban, working-class, predominantly minority men and women was interviewed by telephone to assess knowledge, beliefs, and barriers relevant to colorectal cancer (CRC) and CRC screening. More than half (53.9%) were unable to name a CRC screening test. Misconceptions were common. Dispelling inaccurate beliefs, establishing an individual's preference for fecal occult blood tests or flexible sigmoidoscopy, and helping individuals take a proactive role in the receipt of CRC screening are important goals for health education efforts aimed at increasing rates of CRC screening. Participants' willingness to engage in detailed telephone conversations about CRC and CRC screening was encouraging.

Detection of mesial temporal lobe hypoperfusion in patients with temporal lobe epilepsy by use of arterial spin labeled perfusion MR imaging.

BACKGROUND AND PURPOSE: Interictal hypometabolism has lateralizing value in cases of temporal lobe epilepsy and positive predictive value for seizure-free outcome after surgery to treat epilepsy. Alterations in regional cerebral metabolism can also be inferred from measurements of regional cerebral perfusion. The purpose of this study was to determine the feasibility of detecting cerebral blood flow (CBF) asymmetries in the mesial temporal lobes using continuous arterial spin labeling perfusion MR imaging, which is a noninvasive method for calculating regional CBF. METHODS: Twelve patients with medically refractory temporal lobe epilepsy who underwent preoperative evaluation for temporal lobectomy and 12 normal control participants were studied retrospectively. Absolute and normalized mesial temporal CBF measurements were compared between the patient and control groups. Lateralization based on a perfusion asymmetry index was compared with metabolic ((18)[F]-fluorodeoxyglucose positron emission tomography) and hippocampal volumetric asymmetry indices and with clinical lateralization. RESULTS: Mesial temporal CBF was more asymmetric in patients with temporal lobe epilepsy than in normal control participants, although asymmetric mesial temporal CBF was also found in normal participants, with the left side dominant. Ipsilateral mesial temporal CBF was significantly decreased compared with contralateral mesial temporal CBF in patients with temporal lobe epilepsy. Global CBF measurements were significantly decreased in patients compared with control participants. Asymmetry in mesial temporal blood flow in patients persisted after normalization to global CBF. Lateralization using continuous arterial spin labeling perfusion MR imaging asymmetry index significantly correlated with lateralization based on (18)[F]-fluorodeoxyglucose positron emission tomography hypometabolism, hippocampal volumes, and clinical evaluation. CONCLUSION: Continuous arterial spin labeling perfusion MR imaging can detect interictal asymmetries in mesial temporal lobe perfusion in patients with temporal lobe epilepsy. This technique is readily combined with routine structural assessment and potentially offers an inexpensive and noninvasive means of screening for asymmetries in interictal mesial temporal lobe function.

Quantitative apparent diffusion coefficient measurements in term neonates for early detection of hypoxic-ischemic brain injury: initial experience.

PURPOSE: To determine the utility of using quantitative apparent diffusion coefficient (ADC) values as an objective means of early detection of brain injury caused by hypoxic-ischemic encephalopathy (HIE) in term neonates. MATERIALS AND METHODS: Conventional images, diffusion-weighted images, ADC maps, and clinical charts from 13 term neonates clinically suspected of having HIE were retrospectively reviewed. Four term neonates without HIE served as control subjects. ADC values were calculated in predefined regions in patients and compared with those in control subjects. A Student t test was performed for each region to compare patients and control subjects. RESULTS: Abnormalities were more easily detected on diffusion-weighted images and ADC maps, compared with conventional images. ADC values in patients with HIE were significantly different from those of control subjects in the posterior limb of the internal capsule, corona radiata, posterior frontal white matter, and parietal white matter bilaterally. CONCLUSION: Evaluation of ADC maps can improve conspicuity of hypoxic-ischemic injury in the acute and/or subacute setting (within 12 days of insult), and calculation of ADC values can provide an objective measure of hypoxic-ischemic injury.

MRI identification of early white matter injury in anoxic-ischemic encephalopathy.

BACKGROUND: Anoxic-ischemic encephalopathy (AIE) affects the gray matter more than the white matter. Recent animal experiments suggest that the white matter is more sensitive to ischemia than previously thought. The authors describe the MRI findings in seven patients with AIE who demonstrate early preferential involvement of the white matter. MATERIALS AND METHODS: A retrospective case series study was performed, including seven patients with AIE who underwent MRI of the brain within 7 days of insult. Demographic information, type of insult, clinical examination findings, EEG findings, and clinical outcome were obtained. MRI studies were reviewed with specific attention to the cortex, deep gray matter, and the white matter structures. Mean apparent diffusion coefficient (ADC) was calculated in regions of interest placed in the cerebellar hemispheres, putamen, thalamus, splenium of corpus callosum, centrum semiovale, and medial frontal cortex. RESULTS: The causes of AIE were cardiac arrhythmias in two patients, myocardial infarction in one, drug overdose in two, carbon monoxide poisoning in one, and respiratory failure and sepsis in one. The median time to MRI was 2.5 days. Symmetric areas of restricted diffusion were found in the periventricular white matter tracts (7/7 patients), the corpus callosum (6/7 patients), internal capsule (5/7 patients), and the subcortical association fibers (3/7 patients). ADC maps confirmed the restricted diffusion. Gray matter involvement was seen in three patients, and was more prominent on conventional imaging sequences compared with diffusion-weighted imaging. A subtle decrease in mean ADC was seen in cortex. CONCLUSIONS: Prominent, symmetric restricted diffusion can occur early after AIE in white matter, whereas gray matter involvement may be less prominent. Further studies involving a larger sample and serial imaging are required to confirm these preliminary findings.

The relationship of life stressors and maternal depression to pediatric asthma morbidity in a subspecialty practice.

OBJECTIVE: To examine the relationships among demographic characteristics, caregiver life stressors, and depressive symptoms of mothers and their children's asthma morbidity. SETTING: Three pediatric asthma subspecialty programs, 2 in the inner city and 1 in the suburbs. DESIGN: Cross-sectional census sample of caregivers of children with asthma: interviews mostly with mothers (N = 123) regarding their children's asthma symptoms and health care utilization. Information collected on demographics and caregivers' own recent life stressors and depressive symptoms. SUBJECTS: Caregivers of children ages 18 months to 12 years with asthma at their subspecialty visit. MEASURES: Structured interviews: a survey instrument prepared for this study and standardized instruments for depression (Center for Epidemiologic Studies--Depression) and life stressors (Crisis in Family Systems). RESULTS: A total of 32% of respondents' children had high asthma morbidity, 28% intermediate, and 40% low. Caregiver life stressors and depression and the children's sex showed the strongest relationships to asthma morbidity in a model that also included race, residence, and Medicaid status. Children were more likely to have high morbidity if they had caregivers with more depressive symptoms and negative life stressors and if they were female. CONCLUSIONS: Respondents experienced many life stressors and symptoms of depression while managing their children's illness. Caregivers' lives may affect their children's asthma morbidity, offering empirical evidence for the potential value of targeted case management for children in subspecialty care.

Update on the epidemiology of osteoporosis.

Osteoporosis is a major public health problem that affects the entire aging population. This report provides an update on the epidemiology of osteoporosis and its associated fractures. Published studies from 1997 to the present are highlighted. The current US prevalence estimates for osteoporosis, trends in fracture incidence rates, and latest reports on the morbidity, mortality, and costs attributable to osteoporotic fractures are discussed. Recent advances in our understanding of risk factors associated with osteoporosis and related fractures are reviewed. Special attention is paid to the rapid progress being made in the field of genetics, the growing importance of nutrition, and the new questions being raised as to the influence of hormonal factors on bone mineral density and fracture risk. New studies linking osteoporosis to several other important diseases in women including breast cancer, osteoarthritis, and stroke are also reviewed.

Factors associated with calcium absorption efficiency in pre- and perimenopausal women.

BACKGROUND: The amount of calcium ingested by an individual may affect several chronic conditions, including osteoporosis, hypertension, and colon cancer. However, individuals vary in their ability to absorb the calcium they consume. OBJECTIVE: The purpose of this study was to examine sources of interindividual variation in the efficiency of calcium absorption in women. DESIGN: Fractional calcium absorption was estimated in 142 healthy pre- and perimenopausal women. Dietary habits, lifestyle factors, calciotropic hormones, and vitamin D receptor gene polymorphisms were also assessed. RESULTS: Calcium absorption values averaged 35% and ranged from 17% to 58%. Fractional calcium absorption was positively associated with body mass index (r = 0.22, P = 0.007), dietary fat intake (r = 0.29, P = 0.001), serum 1,25 dihydroxyvitamin D [1,25(OH)(2)D] concentrations (r = 0.23, P = 0. 006), and parathyroid hormone concentrations (r = 0.21, P = 0.015). Fractional calcium absorption was inversely associated with total calcium intake (r = -0.18, P = 0.030), dietary fiber intake (r = -0. 19, P = 0.028), alcohol consumption (r = -0.14, P = 0.094), physical activity (r = -0.22, P = 0.007), and symptoms of constipation (r = -0.16, P = 0.059). In stepwise regression analysis, dietary fat, dietary fiber, serum 1,25(OH)(2)D, and alcohol consumption emerged as independent predictors of calcium absorption, explaining 21.02% of the observed variation. Women in the lowest tertile of the ratio of dietary fat to fiber had 19% lower fractional calcium absorption values than did women in the highest tertile of ratio of dietary fat to fiber (test of trend, P < 0.001). CONCLUSIONS: There is a wide range of calcium absorption values in healthy women. The amount of dietary fat consumed relative to dietary fiber appears to have an important role in determining differences in calcium absorption performance among individuals.