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11.
The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk. INTRODUCTION: Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy. We examined how the application of such absolute risk classification systems influences the prevalence of those considered to be at high risk for osteoporotic fracture and compared these systems to one based solely on BMD. MATERIALS AND METHODS: Using 6646 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, randomly selected, population-based cohort, we assessed three different systems for determining prevalence of high risk for osteoporotic fracture: a BMD-based system; a simplified risk factor system incorporating age, sex, BMD, and two clinical risk factors; and a comprehensive system, incorporating age, sex, BMD, and seven clinical risk factors. The 10-year absolute risks of incident fragility fracture were compared across systems using three different high-risk thresholds. RESULTS: The prevalence of a T score < or = -2.5 was 18.8% (95% CI: 17.7-19.9%) in women and 3.9% (95% CI: 3.0-4.7%) in men. Using a 15% 10-year risk of fracture threshold, the prevalence of women at high risk increased to 46.9% (95% CI: 45.4-48.4) and 42.5% (95% CI: 41.1-43.9) when the comprehensive and simplified risk factor classification systems were used, respectively. Using a 25% 10-year absolute risk threshold, the prevalence of high risk was similar to that of the BMD-based system, whereas the 20% threshold gave intermediate rates. All thresholds analyzed resulted in an increased prevalence of older women at high risk for fracture, whereas only the 15% 10-year risk of fracture threshold resulted in an increase in the prevalence of men at high risk. CONCLUSIONS: The application of risk factor-based systems results in an increased prevalence of older women at high risk. The prevalence of individuals at high risk may increase with changes to the methods used to determine those who are eligible for therapy. These data have important implications for the pattern of care and costs of treating osteoporotic fractures.  相似文献   
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The number of left ventricular assist device (LVAD) implantations is growing as a result of increased waiting periods for cardiac transplantation and the decreased availability of organ donors. Furthermore, the Food and Drug Administration (FDA) has approved permanent LVAD support. After an acute hospitalization, patients with LVADs may need prolonged convalescence in a healthcare facility because they have complex medical needs and are physically disabled. Admission criteria need to be developed as essential patient and nursing competencies need to be defined as a part of a successful LVAD program in an acute rehabilitation center. Acute rehabilitation centers can help patients with LVADs transition to a home setting.  相似文献   
14.
Mapping brain size and cortical gray matter changes in elderly depression.   总被引:1,自引:0,他引:1  
BACKGROUND: In elderly depression, volumetric brain imaging findings suggest abnormalities of the frontal lobe, particularly the orbitofrontal cortex, and the hippocampus. No studies to date have mapped cortical abnormalities over the entire brain surface in major depression. Here, we conducted detailed spatial analyses of brain size and gray matter within the cortical mantle in elderly patients with major depression. METHODS: High-resolution, three-dimensional, structural magnetic resonance imaging data and cortical pattern matching methods were used in 24 depressed elderly patients and 19 group-matched controls to measure local brain size and proportions of gray matter at thousands of homologous cortical surface locations. RESULTS: Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex. CONCLUSIONS: Complex cortical changes may contribute to the brain size reduction of the orbitofrontal cortex and to the gray matter abnormalities detected in orbitofrontal cortex and temporoparietal cortices, thereby providing a potentially new window into the pathophysiology of elderly depression.  相似文献   
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PURPOSE: Evaluate the effectiveness of body mass index (BMI) tables placed in exam rooms as an intervention to encourage providers to calculate and record BMI scores in patients' medical records. DESIGN: In a prospective cohort design, medical record data for 276 adult patients at a federally funded community health center in New England were examined from August 2000 to August 2002 following the intervention. METHODS: Prominent, multicolored, laminated BMI tables were posted in the exam rooms of one of the study site's three primary health care teams. Medical record data collected included documentation of BMI calculation in medical records, documentation of an obesity diagnosis, and inclusion of heights and current weights. Frequency distributions were calculated; chi-square tests were used to identify associations. FINDINGS: In contrast to the comparison teams, patients on the intervention team were more likely to have BMI recorded in the medical record. A statistically significant increase in the diagnosis of obesity was observed throughout the health center after the intervention. CONCLUSIONS: Posting BMI tables in exam rooms contributed to increased BMI documentation in patients' medical records.  相似文献   
16.
Precise and accurate inversion-recovery (PAIR) magnetic resonance (MR) measurements of T1 were obtained in eight brain regions and cerebrospinal fluid of 26 healthy volunteers. Accuracy of the technique was assessed by measuring T1 in small fluid volumes with the PAIR technique and with two independent spectroscopic techniques. The mean difference between T1 measured with PAIR and with the two spectroscopic techniques was 3.1% ± 1.3. The precision (reproducibility) of measurements with the PAIR technique was excellent. The coefficient of variation (CV) across 16 measurements in a head phantom was 2.0%, compared with a CV of 2.7% across 45 separate measurements in a single subject. The within-subject CV was 1.8% ± 0.6 in white matter and 1.4% ± 1.0 in basal ganglia. The between-subject CV in 26 healthy volunteers was 3.6% ± 0.6 in white matter and 4.1% ± 1.9 in basal ganglia. Comparison between a patient with an active recurrent brain tumor and an agematched patient with an inactive brain tumor showed that T1 was significantly elevated throughout the brain of the active-tumor patient, especially in white matter tracts, even though no tumor or edema was detected in the white matter on standard MR images. Comparisons between five brain tumor patients and four healthy volunteers of similar age showed that T1 was significantly and substantially elevated throughout the white matter tracts and in the caudate nucleus, putamen, and thalamus. These results are consistent with the hypothesis that white matter tracts are selectively vulnerable to edema and that T1 increases in white matter are a sensitive indicator of patient status or tumor aggressiveness.  相似文献   
17.
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.  相似文献   
18.
To better understand the impact of incident Parkinson's disease (PD) on the Veteran's Health Administration (VHA) and to develop methods applicable to future epidemiological research, we performed a medical record review study at a tertiary referral VHA medical center. Searching the local data base, we identified 782 veterans with diagnostic codes for PD or secondary parkinsonism (SP) between 1998 and 2000. Based on structured medical record review, a movement disorders specialist confirmed diagnoses for incident parkinsonism cases. Among the 782, 191 incident parkinsonism cases were identified (100 PD, 75 SP, and 16 Parkinson's Plus). Incident PD cases were older at diagnosis (74.5 vs. 70.4 yr; P < 0.05) and more likely to be white (81% vs. 62; P < 0.07) than incident SP cases. Diagnostic codes were insufficient to distinguish between incident PD and SP (positive predictive value, 57% and 39%, respectively), and VHA sources failed to identify 21% of confirmed deaths among the incident PD cohort by November 2004. Although the large number of incident cases identified suggests PD is an important cause of disability among elderly VHA users, observed limitations of VHA sources for identifying incident PD cases and determining their vital status should be considered when designing future studies.  相似文献   
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Even though continued smoking by cancer patients adversely affects survival and quality of life, about one third of patients who smoked prior to their diagnosis continue to smoke after their diagnosis. The implementation of smoking cessation treatments for cancer patients has been slowed by the lack of data on correlates of tobacco use in this population. Thus, this longitudinal study assessed demographic, medical, addiction, and psychological predictors of tobacco use among 74 head, neck, and lung cancer patients. Multivariable binary logistic regression analyses, with outcome categorized as smoker or nonsmoker, indicated that the likelihoodthat patients would be a smoker was associated with lower levels of perceived risk and a higher level of quitting cons. Multivariable nominal logistic regression, with outcome classified as continuous smoker, continuous quitter, relapser, or follow-up quitter, indicated that: (a) patients categorized as continuous smokers reported significantly lower quitting self-efficacy than follow-up quitters and continuous quitters, (b) relapsers reported a significantly lower level of quitting self-efficacy than either follow-up quitters or continuous quitters, and (c) continuous smokers exhibited a significantly lower level of risk perceptions than continuous abstainers. These findings can be useful for the development and evaluation of treatments to promote smoking cessation among cancer patients. Support for this study was provided by National Institutes of Health Grants CA57708, CA06927, CA88610, CA95678, and CA76644.  相似文献   
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