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41.

Background

Visual analogue scales (VAS) are often used to measure health-related quality of life (HRQoL). However, when such scales contain ambiguous anchors like “best imaginable health state,” they produce answers that are difficult to interpret, as such anchors are interpreted differently by respondents of different age. This phenomenon that people’s interpretation of subjective response scales changes in response to changing circumstances is known as scale recalibration. The current study attempts to investigate whether scale recalibration in a patient sample with cognitive limitations and proxies differs from the general population.

Methods

The participants in the current study were 151 pairs of community-dwelling patients with dementia and their proxies. They were administered three VASs with different upper anchors; (A) “best imaginable health state,” (B) “best imaginable health state for someone your age,” and (C) “best imaginable health state for a 25-year-old.” From literature, we inferred a conceptual model for the general population that predicts the ordinal relationship of the VASs to be B ≥ A ≥ C. This rank order is tested by repeated measure ANOVA’s in the aforementioned populations.

Results

VAS scores of patients with dementia were in line with the conceptual model. Proxy VAS scores for assessing patient HRQoL were not in line with the model: A > B > C. In addition, proxy VAS scores for assessing their own health were not in line with the model: A > B > C.

Conclusion

Patients with dementia use the VAS in a similar way to the general population. Proxies assessing either patients or themselves differ from the general population.  相似文献   
42.
43.
The purpose of this study was to investigate whether an age-associated impaired acute-phase response exists. Nine healthy elderly volunteers (median, 66 years; range, 61 to 69 years) and eight young controls (median, 24 years; range, 20 to 27 years) were given an intravenous bolus of endotoxin (2 ng/kg). The rectal temperature was monitored continuously, and blood samples for cytokine measurements were obtained before endotoxin administration as well as 0.5, 1, 1.5, 2, 3, 4, 8, 12, and 24 h after the injection. The elderly subjects showed a more prolonged fever response compared to the young controls. Levels of tumor necrosis factor alpha (TNF-α), soluble TNF receptors (sTNFR-I), interleukin-6 (IL-6), IL-8, IL-10, and IL-1 receptor antagonist (IL-1ra) in plasma increased markedly following endotoxin administration in both groups. The elderly group showed larger initial increases in TNF-α and sTNFR-I levels and prolonged increased levels of sTNFR-I. Monocyte concentrations decreased in both groups, with the elderly group showing a more rapid decrease and a slower subsequent increase than did the young group. Furthermore, the elderly group had a more rapid increase in C-reactive protein levels than did the young group. In conclusion, ageing is associated with an altered acute-phase response including initial hyperreactivity, prolonged inflammatory activity, and prolonged fever response.  相似文献   
44.
BACKGROUND: and objective The aim of this study was to determine possible age-associated differences in human blood pressure regulation during an immunological challenge in healthy subjects. METHODS: Eight healthy young volunteers (median age 24 yr) and nine healthy elderly volunteers (median age 66 yr) received an intravenous bolus injection of Escherichia coli endotoxin (2 ng kg(-1)). Blood pressure, heart rate and core temperature were monitored during the first 7 h. Plasma catecholamine concentrations were measured at hourly intervals. RESULTS: The elderly showed a significantly more pronounced decrease in mean arterial pressure 4-7 h after endotoxin administration compared with the young controls (ANOVA; age x time; P < 0.0005). This mainly reflected a decrease in the systolic blood pressure in the elderly. The heart rate of both groups increased without difference between groups. Increased plasma epinephrine concentrations were found 2-3 h after endotoxin administration in both groups. Five hours after the endotoxin challenge, the epinephrine concentration had returned to control values in the elderly group only, in spite of decreased blood pressure. CONCLUSION: In conclusion, healthy elderly subjects fail to maintain a constant mean arterial pressure in response to the immunological challenge of endotoxemia.  相似文献   
45.
Detection of distant metastases and second primary tumors in patients with head and neck squamous cell carcinoma (HNSCC) is of importance because of the impact on treatment and prognosis. The aim of this study was to assess the value of whole-body fluorodeoxyglucose-positron emission tomography (FDG-PET) in detecting distant metastases and second primary tumors below clavicular level in HNSCC compared to chest CT and chest radiography (CXR). Patient records of 149 consecutive patients with a primary HNSCC in whom a whole-body FDG-PET for initial staging was performed were reviewed. FDG-PET showed a sensitivity and specificity for detecting distant disease of 92% and 93%, respectively. Chest CT (n=82) showed a sensitivity and a specificity of 74% and 61% respectively. CXR (n=106) showed a sensitivity and a specificity of 41% and 91%, respectively. FDG-PET was shown to be able to detect distant metastases and second primary tumors in HNSCC with a high sensitivity and specificity. The higher sensitivity of PET compared to chest CT is mainly due to the detection of extrapulmonary malignancy. Sensitivity of PET and CT were similar in detecting intrapulmonary malignancy, but PET specificity was significantly higher. FDG-PET helps to determine the nature of pulmonary lesions and might be considered as a first diagnostic modality for detecting distant disease in advanced HNSCC.  相似文献   
46.
Impaired tumor suppressor functions, such as deficient p53, are characteristic for glioblastoma multiforme (GBM) and can cause resistance to DNA-damaging agents like cisplatin. We have recently shown that the INhibitor of Growth 1 (ING1) tumor suppressor is down-regulated in malignant gliomas and that the decrease of ING1 expression correlates with histological grade of malignancy, suggesting a role for ING1 in the pathogenesis and progression of malignant gliomas. Based on this background, the purpose of our current study was to examine the potential impact of ING1 protein levels on DNA-damage response in GBM. Using LN229 GBM cells, which express ING1 proteins and harbor mutant TP53, we are the first to show that DNA damage by cisplatin or ionizing radiation differentially induced the two major ING1 splicing isoforms. The p47 ING1a isoform, that promotes deacetylation of histones, thus formation of heterochromatic regions of DNA, which are less susceptible to DNA damage, was preferentially induced by >50-fold. This might represent a response to protect DNA from damage. Also, ING1 knockdown by siRNA accelerated transit of cells through G1 phase, consistent with ING1 serving a tumor suppressor function, and caused cells to enter apoptosis more rapidly in response to cisplatin. Our results indicate that malignant gliomas may down-regulate ING1 to allow more efficient tumor growth and progression. Also, ING1 down-regulation may sensitize GBM cells with deficient p53 to treatment with cisplatin. U. G. Tallen and M. Truss contributed equally to this work.  相似文献   
47.
The Impact of Migraine on Health Status   总被引:3,自引:0,他引:3  
Problems.-What is the effect of migraine on health status, defined as the patient's physical, psychological, and social functioning? And, suppose that the health status of migraine sufferers appears to be impaired, to what extent is this a consequence of migraine-associated comorbidity rather than of migraine itself? Methods.-A group of 846 migraineurs, selected from the general population following IHS criteria, and a control group were surveyed with the Medical Outcomes Study 36-item Short-Form Health Survey, Nottingham Health Profile, EuroQol instrument, end the COOP/WONCA charts. Questions on demographic characteristics and comorbidity were included. Results.-The health status of migraineurs appeared to be significantly impaired in comparison to the control group. Because statistical significance is distinct from relevance, effect size estimators were employed. Although the direction of the differences indicated consistently a worse health status of the migraineurs, regardless of the instrument used, the sizes of the differences were small to medium. Self-reported comorbidity, especially depression, was more prevalent in the migraine group. However, this offered only a partial explanation for the impaired health status of the migraine group. Conclusions.-Migraine has an independent moderately deteriorating effect on the daily functioning of individuals.  相似文献   
48.
In this study we compared the feasibility, internal structure and psychometric characteristics (internal consistency, test-retest reliability, construct validity) of two widely used generic health status measures, i.e. the Nottingham Health Profile (NHP) and the Sickness Impact Profile (SIP) when employed among a sample of patients on renal dialysis (n=63). The NHP was found to be more feasible, i.e. shorter and less difficult, than the SIP. The NHP scales showed somewhat higher levels of internal consistency (mean =0.67, range=0.39–0.80) than the SIP scales (mean =0.65, range=0.14–0.82). Test-retest reliability with a 24-hour interval was acceptable for most NHP scales (not available for the SIP in this study). Intercorrelations between the NHP scales were somewhat weaker than those for the SIP, and the expected patterns of scale intercorrelations were largely confirmed. The overall pattern of correlations between NHP scales and SIP scales was consistent with expectations, although the correlations were generally rather weak. Correlations between NHP scales and SIP scales and instruments measuring mainly physical functioning (ADL, Karnofsky) were largely as expected. Similarly, correlations between NHP scales and SIP scales and instruments measuring mainly psychological functioning [STAI (anxiety), SDS-Zung (depression)] were also as expected, although here the correlations were weaker for the SIP when compared with the NHP. The Index of Well-being exhibited intra-class correlations >0.3 with one SIP scale and with five out of six NHP scales. Common factor analysis, yielding a two-factor solution with a physical and a mental factor of equal importance, showed the SIP scales to load more on the physical factor, while the NHP scales loaded more on the mental factor. The NHP generally performed better than the SIP in terms of feasibility and internal consistency. Physical functioning is emphasized in the SIP, whereas the emphasis of the NHP lies on mental functioning. The analysis confirmed to some extent the intentions of the constructors of NHP and SIP respectively, i.e. the NHP to be a measure of perceived health and the SIP to be a more functional measure.  相似文献   
49.
50.
The aim of this prospective study was to evaluate the value of (18)F-FDG PET for the assessment of chemotherapy response in patients with non-small cell lung cancer. Furthermore, part of the objective of this study was to compare 2 methods to quantify changes in glucose metabolism. METHODS: In 51 patients, dynamic (18)F-FDG PET was performed before and at 5-8 wk into treatment. Simplified methods to measure glucose metabolism (standardized uptake value [SUV]) and quantitative measures (metabolic rate of glucose [MR(Glu)]), derived from Patlak analysis, were evaluated. The overall survival and progression-free survival with respect to MR(Glu) and SUV were calculated using Kaplan-Meier estimates. Fractional changes in tumor glucose use were stratified by the median value and also the predefined EORTC (European Organization for Research and Treatment of Cancer) metabolic response criteria, and criteria applying cutoff levels similar to those of RECIST (Response Evaluation Criteria in Solid Tumors) were evaluated. RESULTS: When stratifying at the median value of DeltaMR(Glu) and DeltaSUV, the difference in overall survival (P = 0.017 for DeltaMR(Glu), P = 0.018 for DeltaSUV) and progression-free survival (P = 0.002 for DeltaMR(Glu), P = 0.0009 for DeltaSUV) was highly significant. When applying the predefined criteria for metabolic response, the cutoff levels as also used for size measurement (RECIST) showed significant differences for DeltaSUV between response categories in progression-free survival (P = 0.0003) as well as overall survival (P = 0.027). CONCLUSION: The degree of chemotherapy-induced changes in tumor glucose metabolism as determined by (18)F-FDG PET is highly predictive for patient outcome, stratifying patients into groups with widely differing overall survival and progression-free survival probabilities. The use of (18)F-FDG PET for therapy monitoring seems clinically feasible, because simplified methods to measure tumor glucose use (SUV) are sufficiently reliable and can replace more complex, quantitative measures (MR(Glu)) in this patient population.  相似文献   
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