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Víctor Abraira

Publications and source records attributed to Víctor Abraira.

14 recordsLinked to original sources

The social tariff of EQ-5D is not adequate to assess quality of life in patients with low back pain.

BACKGROUND: We compared the quality of life perceived by patients with non-specific low back pain with that predicted by the social tariff of the Spanish version of EQ-5D questionnaire. METHODS: For each health state of the EQ-5D, an adjusted tariff for patients with back pain was obtained using a linear regression model in which the linear effect of the three levels of response for each of the five domains of the EQ-5D was assumed. These coefficients were compared with those obtained for the general Spanish population. In another model, equal in structure to the standard "Dolan N3" model, the linear effect of the five domains was not assumed. RESULTS: In 633 patients, 93 health states were recorded. Significant differences in the coefficients of self-care (p = 0.003) and the maximum level of severity in any dimension (p < 0.0001) were observed. The social tariff of the healthy population is different from the tariff of low back pain patients, with general population values being lower than those of patients, particularly in the 211 health states in which any dimension is at level 3. Weights of the different EQ-5D dimensions showed a non-linear effect on the patients' quality of life. CONCLUSION: Methods used to develop the social tariff for the Spanish version of EQ-5D were inadequate. In addition, this study shows that values given by the general population are different from those of low back pain patients, further confirming that the social tariff of EQ-5D should not be used with actual patients.

Adolescent↗

Accuracy of monoclonal stool antigen test for the diagnosis of H. pylori infection: a systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review and a meta-analysis of accuracy of monoclonal stool antigen test (SAT) for the diagnosis of Helicobacter pylori infection. METHODS SELECTION OF STUDIES: assessing the accuracy of monoclonal SAT for the diagnosis of H. pylori infection. SEARCH STRATEGY: electronic and manual bibliographical searches. DATA EXTRACTION: independently done by two reviewers. DATA SYNTHESIS: meta-analyses combining the sensitivities, specificities, and likelihood ratios (LRs) of the individual studies. RESULTS: Twenty-two studies, including 2,499 patients, evaluated the monoclonal SAT before eradication therapy. Pooled sensitivity, specificity, LR+, and LR- were: 0.94 (95% CI 0.93-0.95), 0.97 (0.96-0.98), 24 (15-41), and 0.07 (0.04-0.12). The accuracy of both monoclonal and polyclonal SAT was evaluated together in 13 pretreatment studies, and higher pooled sensitivity was demonstrated with the monoclonal technique (0.95 vs 0.83). Twelve studies, including 957 patients, assessed the monoclonal SAT to confirm eradication after therapy. Pooled sensitivity, specificity, LR+, and LR- were 0.93 (0.89-0.96), 0.96 (0.94-0.97), 17 (12-23), and 0.1 (0.07-0.15). Both tests were evaluated together in eight post-treatment studies and, again, the monoclonal technique showed higher sensitivity (0.91 vs 0.76). Heterogeneity among studies disappeared when a single outlier study was excluded. Subanalysis depending on the reference method, the study population, or the study quality showed similar results. CONCLUSION: Monoclonal SAT is an accurate noninvasive method both for the initial diagnosis of H. pylori infection and for the confirmation of its eradication after treatment. The monoclonal technique has higher sensitivity than the polyclonal one, especially in the post-treatment setting.

Antigens, Bacterial↗

Accuracy of Helicobacter pylori diagnostic tests in patients with bleeding peptic ulcer: a systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review and a meta-analysis of diagnostic accuracy of the different tests aimed to detect Helicobacter pylori infection in patients with upper gastrointestinal bleeding (UGIB). METHODS SELECTION OF STUDIES: assessing the accuracy of H. pylori diagnostic methods in patients with UGIB. SEARCH STRATEGY: electronic bibliographical searches. DATA EXTRACTION: independently done by two reviewers. DATA SYNTHESIS: meta-analyses of the different tests were performed combining the sensitivities, specificities, and likelihood ratios (LRs) of the individual studies. RESULTS: Studies showed a high degree of heterogeneity. Pooled sensitivity, specificity, LR+ and LR- (95% confidence interval (CI)) for the different methods were: Rapid urease test (16 studies/1,417 patients): 0.67 (0.64-0.70), 0.93 (0.90-0.96), 9.6 (5.1-18.1), and 0.31 (0.22-0.44). Histology (10 studies/827 patients): 0.70 (0.66-0.74), 0.90 (0.85-0.94), 6.7 (2.5-18.4), and 0.23 (0.12-0.46). Culture (3 studies/314 patients): 0.45 (0.39-0.51), 0.98 (0.92-1.00), 19.6 (4-96), and 0.31 (0.05-1.9). Urea breath test (8 studies/520 patients): 0.93 (0.90-0.95), 0.92 (0.87-0.96), 9.5 (3.9-23.3), and 0.11 (0.07-0.16). Stool antigen test (6 studies/377 patients): 0.87 (0.82-0.91), 0.70 (0.62-0.78), 2.3 (1.4-4), and 0.2 (0.13-0.3). Serology (9 studies/803 patients): 0.88 (0.85-0.90), 0.69 (0.62-0.75), 2.5 (1.6-4.1), and 0.25 (0.19-0.33). CONCLUSION: Biopsy-based methods, such as rapid urease test, histology, and culture, have a low sensitivity, but a high specificity, in patients with UGIB. The accuracy of 13C-urea breath test remains very high in these patients. Stool antigen test is less accurate in UGIB. Although serology seems not to be influenced by UGIB, it cannot be recommended as the first diagnostic test for H. pylori infection in this setting.

Antigens, Bacterial↗

Psychometric characteristics of the Spanish version of the FAB questionnaire.

STUDY DESIGN: Validation of a translated, culturally adapted questionnaire. OBJECTIVES: To translate and culturally adapt the Spanish version of the Fear Avoidance Beliefs Questionnaire (FABQ), and to validate its use in Spanish-speaking patients with low back pain (LBP). SUMMARY OF BACKGROUND DATA: The FABQ is a reliable evaluation instrument for fear avoidance beliefs, which includes two subscales (FAB-Work and FAB-Phys). No validated Spanish version was available. METHODS: Translation/retranslation of the English version of the FABQ was done blindly and independently by a multidisciplinary team. The study was done in 12 primary care centers and 9 hospital outpatient clinics from seven regions in Spain, with 209 acute, subacute, and chronic patients who visited their physician for LBP: 53 in the pilot phase and 156 in the validation phase. Subjects were given the FABQ, two VAS for LBP and referred pain, and the Roland-Morris and SF-12 Questionnaires on their first visit and 14 days later. In the pilot phase, on day 1 test-retest reliability was estimated by giving a second FABQ in which the name and order of the items had been changed. RESULTS: Time necessary to complete the FABQ was [median, P25, P75] 10 minutes (5,15). FABQ values were not normally distributed. Comprehensibility: No request for aid in interpretation was made during the validation phase and no item was left unanswered by >or= 10% of patients. Reliability: Scores [median, P25, P75] of the two FABQ were: 72.00 (47.25, 82.00) and 72.00 (49.50, 83.75), with an intraclass correlation coefficient of 0.9668 (95% confidence interval, 0.9421,0.9823). Mean of kappa values for all items was 0.743. Internal Consistency: Cronbach's alpha was 0.9337. VALIDITY: Values of FAB and FAB-Work were >37% higher for patients on sick leave. For FAB-Phys differences were below 8%. FABQ, FAB-Work and FAB-Phys strongly correlated with disability on days 1 and 15. CONCLUSIONS: The Spanish version of the FABQ has good comprehensibility, internal consistency, and reliability. It cannot be analyzed parametrically, but only nonparametrically. The total FABQ is at least as valid as its subscales and simpler to score, making it more suitable for routine clinical use.

Avoidance Learning↗

Accuracy of B-type natriuretic peptide levels in the diagnosis of left ventricular dysfunction and heart failure: a systematic review.

OBJECTIVES: To evaluate the accuracy of B-type natriuretic peptide levels (BNP) in the diagnosis of heart failure and left ventricular dysfunction. DATA SOURCES: Electronic search in Medline, Embase, Cochrane Library and Medion database, and hand search of reference lists. REVIEW METHODS: We have included published studies on the accuracy of BNP which had both sufficient information to construct the 2x2 diagnostic cross table and an appropriate spectrum of patients. RESULTS: Fifty five studies (16,730 patients) were analyzed. The main determinants of diagnostic accuracy were the reference standard analyzed (clinical heart failure versus left ventricular dysfunction), and the methodological quality of the study. BNP levels were highly accurate for the diagnosis of clinical heart failure (diagnostic OR=41; 95% CI 23-74). The negative likelihood ratios were homogeneous, and useful for excluding the existence of heart failure (pooled negative likelihood ratio=0.11; 95% CI 0.08-0.16). The studies focused on the identification of left ventricular dysfunction were heterogeneous, with indications of publication bias, and showed less overall diagnostic accuracy than studies focused on heart failure. CONCLUSIONS: BNP levels are useful for ruling out heart failure. The accuracy of BNP for identifying patients with systolic dysfunction is more limited.

Cardiac Output, Low↗

The transition from acute to subacute and chronic low back pain: a study based on determinants of quality of life and prediction of chronic disability.

STUDY DESIGN: Follow-up study. OBJECTIVES: To document differences between acute and subacute low back pain (LBP) based on the risk of developing chronic disability and on the correlation between pain, disability, and quality of life. SUMMARY OF BACKGROUND DATA: The subacute stage should identify the time in which the risk of developing chronic disability increases and specific measures should be considered, but its definition is currently inconsistent. METHODS: 366 patients were given Visual Analog Scales (VAS) for LBP and referred pain (RP), Roland-Morris questionnaires (RMQs), and EuroQol (EQ) questionnaires on their first visit and 14 and 59 days later. RESULTS: Median duration of pain when entering the study was 4 days (P25, P75: 2,10). Simple correlations among LBP, VAS, and RMQ were r = 0.407 (day 1), 0.688 (day 15), and 0.739 (day 60). Among LBP, VAS, and EQ, r = -0.523, r = -0.701, and r = -0.760. Among RP, VAS, and RMQ, r = 0.280, r = 0.561, and r = 0.583. Between RP, VAS, and EQ, r = -0.306, r = -0.534 and r = -0.600. Between RMQ and EQ, r = -0.650, r = -0.765 and r = -0.815. In 42 patients, disability did not improve throughout the study period, and a prestudy duration of > or = 14 days was the only independent predictor. All these models were significant at the P < 0.007 level. Improvement in quality of life was more likely to occur in patients in which disability improved [odds ratio (OR), 18.29; 95% CI; 8.64, 38.73; P < 0.001]. As opposed to acute patients, in those with a prestudy duration of pain of > or = 14 days, on day 60 RP had no influence on disability, and LBP had no influence on quality of life. CONCLUSION: LBP influences disability and quality of life more than RP. Disability is predicted by pain duration and quality of life is predicted by disability, but pain severity predicts neither one of them. Changes related to determinants of disability and quality of life, and to the prediction of chronic disability, appear 14 days after the onset of pain, supporting that cutoff point for considering a patient as being subacute.

Acute Disease↗

[Cardiac rehabilitation in patients with myocardial infarction: a 10-year follow-up study].

INTRODUCTION AND OBJECTIVES: Very little information is available on the effect of cardiac rehabilitation programs on long-term survival. The primary aim of this study was to assess the effect of a structured cardiac rehabilitation program on mortality in patients who had suffered acute myocardial infarction. The secondary endpoint was the effect on morbidity. PATIENTS AND METHOD: The study included 180 low-risk male patients aged under 65 years. Patients were randomly assigned to one of 2 groups: 90 entered into a comprehensive cardiac rehabilitation program, and 90 served as a control group. The mean follow-up period was 10 years. RESULTS: All-cause mortality was significantly lower in the intervention group: the 10-year survival rate was 91.8% in the intervention group compared with 81.7% in the control group (P=.04). There was also a decrease in cardiovascular mortality, though it was not statistically significant: the 10-year survival rate was 91.8% in the intervention group compared with 83.8% in the control group (P=.10). The incidence of non-fatal complications was lower in the intervention group (35.2% vs 63.2%, P=.03), as was the incidence of unstable angina (15.7% vs 33.9%, P =.02) and cardiac heart failure (3.0% vs 14.4%, P=.02), and the need for coronary intervention (8.4% vs 22.9%, P=.02). CONCLUSIONS: The application of a comprehensive cardiac rehabilitation program significantly decreased long-term mortality and morbidity in low-risk patients after acute myocardial infarction.

Adult↗

Influence of biologic markers on the outcome of Hodgkin's lymphoma: a study by the Spanish Hodgkin's Lymphoma Study Group.

PURPOSE: Current therapies fail to cure a significant proportion of patients with Hodgkin's lymphoma (HL). Predictive systems for stratification of the disease and selection of treatment based on sets of clinical variables, such as the international prognostic score (IPS), are of relatively small practical value. The predictive use of biologic parameters has so far provided limited and inconsistent results. Here we explore the influence of a set of molecular markers on the outcome of HL. PATIENTS AND METHODS: Forty molecular markers involved in B-cell differentiation and activation, signal transduction, cell cycle, and apoptosis control were analyzed in 259 classic HL patient cases by using tissue microarrays. Univariate analysis was performed to evaluate the influence of markers on favorable outcome (complete remission of > 12 months). Significant variables were included in a multivariate logistic regression analysis, and the probability of favorable outcome was estimated. RESULTS: Univariate analysis revealed four molecular markers that predicted outcome, and the multivariate analysis showed p53, Bcl-X(L), and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL) to have independent significance. The combination of these factors determined two groups of patients (group I, zero to one factor; group II, two to three factors) with a probability of a favorable outcome of.948 and.687, respectively. A multivariate Cox's model shows that these biologic risk groups have special predictive power in low-IPS patients. CONCLUSION: The data from this exploratory study suggest that the accumulation of molecular events seems to influence the outcome of HL, particularly in the low-IPS group.

Adolescent↗

Correlation between pain, disability, and quality of life in patients with common low back pain.

STUDY DESIGN: Correlation among previously validated questionnaires. OBJECTIVES: To determine the correlation between pain, disability, and quality of life in patients with low back pain. SUMMARY OF BACKGROUND DATA: The Visual Analogue Scale (VAS), and the Roland-Morris (RMQ), Oswestry (OQ), and EuroQol (EQ) Questionnaires are validated instruments to assess pain, low back pain-related disability, and quality of life. METHODS: The study was done in the primary care setting, in Mallorca, with 195 patients who visited their physician for LBP. Individuals were given the VAS, RMQ, OQ, and EQ on their first visit and 14 days later. RESULTS: Median duration of pain when entering the study was 10 days (P25,P75: 3, 40). On day 1, simple correlation was r = 0.347 between VAS and RMQ, r = -0.422 between VAS and EQ, and r = -0.442 between RMQ and EQ. On day 15, simple correlation was r = 0.570 between VAS and RMQ, r = -0.672 between VAS and EQ, and r = -0.637 between RMQ and EQ. Multiple linear regression models showed that, on day 1, the VAS score explains 12% of the RMQ score and the VAS and RMQ scores explain 27% of the EQ score. On day 15, the VAS score explains 33% of the RMQ score, and the VAS and RMQ scores explain 58% of the EQ score. On day 1, a 10% increase in VAS worsens disability by 3.3% and quality of life by 2.65%. On day 15, a 10% increase in VAS worsens disability by 4.99% and quality of life by 3.80%. Prestudy duration of pain had no influence on any model. All these correlation coefficients and models are significant at the P < 0.001 level. The OQ had lower correlation values with the other three scales, and only two of them were significant. CONCLUSION: Clinically relevant improvements in pain may lead to almost unnoticeable changes in disability and quality of life. Therefore, these variables should be assessed separately when evaluating the effect of any form of treatment for low back pain. The influence of pain and disability on quality of life progresses while they last, and doubles in 14 days. In acute and subacute patients, this increase is not dependent on the previous duration of pain.

Disability Evaluation↗

Presentation and prognosis of gastric cancer in patients aged 80 years and older.

The aim of this study was to analyze the characteristics of the presentation and prognosis of patients aged >/= 80 who were diagnosed with gastric adenocarcinoma. We have used a retrospective cohort study of 2334 patients diagnosed between 1975 and 1993 in northwestern Spain, 263 (11.3%)of whom were >/= 80 years of age. No differences were observed with respect to patients of a younger age at diagnosis regarding the site of the tumor, extension of the disease, or Laurén's histologic type. However, fewer resections with curative intent were performed in the older group (49.1% vs. 30.1%; p < 0.0001). Among those operated on with curative or palliative intent, at the end of the first month the survival probability was 0.9 and the 0.95% confidence interval (CI 95%) was 0.93-0.97 for patients < 80 years of age and 0.93 (CI 95% 0.89-0.98) for the older group ( p = 0.19). At the end of 5 years of follow-up these probabilities were 0.29 (CI 95% 0.27-0.31) and 0.18 (CI 95% 0.14-0.23), respectively ( p < 0.0001). If we consider only those patients undergoing curative resection, the survival probability for the two groups ( p = 0.4) was not statistically different. In conclusion, although the two groups showed similar characteristics at presentation, patients >/= 80 years of age underwent surgery with curative intent less frequently and their general prognosis was worse. Our data support the idea that curative surgery should not be ruled out exclusively for reasons of age.

Adenocarcinoma↗

Abnormal PcG protein expression in Hodgkin's lymphoma. Relation with E2F6 and NFkappaB transcription factors.

The Polycomb group (PcG) of proteins comprises a family of repressors of homeobox genes that play key roles in body formation, haematopoiesis and cell cycle control. In this study, a large-scale analysis of PcG protein expression (BMI1, MEL18, PH1, RNF2, RING1, and RYBP) was performed in 321 Hodgkin's lymphoma (HL) biopsies and in reactive lymphoid tissues using tissue microarrays. The relevance of PcG proteins in HL was also investigated by the simultaneous analysis of PcG and other proteins involved in the control of cell cycle, transcription machinery and lymphoid differentiation. The analysis revealed increased expression of a set of PcG proteins (particularly RYBP and BMI1) in tumour cells in comparison with reactive lymphoid tissue. One of the most striking findings was anomalous RYBP expression in 55% of classical HL cases associated with an unfavourable response to treatment and shorter survival. The data obtained in this study also show an association of PcG proteins with E2F6 and NFkappaB transcription factors. The statistical relationship between PcG and NFkappaB activation was further explored in HL-derived cell lines treated with curcumin, an NFkappaB inhibitor, and TNFalpha. Up- or downregulation of MEL18 was paralleled by loss or gain of activated NFkappaB, which suggests that NFkappaB may regulate expression of this protein. Investigation of the relationship between E2F6 and RING1 by immunofluorescence and confocal analysis, in HL cell lines and paraffin sections, revealed co-expression of both proteins in the same tumour cells. These results allow us to propose that the formation of transcription complexes with E2F6 may modify the functional status of PcG proteins in HSR cells.

Apoptosis↗

Effect of firmness of mattress on chronic non-specific low-back pain: randomised, double-blind, controlled, multicentre trial.

BACKGROUND: A firm mattress is commonly believed to be beneficial for low-back pain, although evidence supporting this recommendation is lacking. We assessed the effect of different firmnesses of mattresses on the clinical course of patients with chronic non-specific low-back pain. METHODS: In a randomised, double-blind, controlled, multicentre trial, we assessed 313 adults who had chronic non-specific low-back pain, but no referred pain, who complained of backache while lying in bed and on rising. Mattress firmness is rated on a scale developed by the European Committee for Standardisation. The H(s) scale starts at 1.0 (firmest) and stops at 10.0 (softest). We randomly assigned participants firm mattresses (H(s)=2.3) or medium-firm mattresses (H(s)=5.6). We did clinical assessments at baseline and at 90 days. Primary endpoints were improvements in pain while lying in bed, pain on rising, and disability. FINDINGS: At 90 days, patients with medium-firm mattresses had better outcomes for pain in bed (odds ratio 2.36 [95% CI 1.13-4.93]), pain on rising (1.93 [0.97-3.86]), and disability (2.10 [1.24-3.56]) than did patients with firm mattresses. Throughout the study period, patients with medium-firm mattresses also had less daytime low-back pain (p=0.059), pain while lying in bed (p=0.064), and pain on rising (p=0.008) than did patients with firm mattresses. INTERPRETATION: A mattress of medium firmness improves pain and disability among patients with chronic non-specific low-back pain.

Adult↗

Higher virological effectiveness of NNRTI-based antiretroviral regimens containing nevirapine or efavirenz compared to a triple NRTI regimen as initial therapy in HIV-1-infected adults.

PURPOSE: To compare outcomes of nonnucleoside reverse transcriptase inhibitors (NNRTIs) nevirapine or efavirenz versus abacavir-based regimens with a backbone of zidovudine and lamivudine as initial therapy of treatment-naive adults with HIV-1 infection in routine clinical care. METHOD: All patients starting their first antiretroviral therapy with any of the studied regimens from January 1999 to December 2002 were included in the analysis. Rates of viral suppression (HIV-RNA below 50 copies/mL) and discontinuation of any component of the regimen were compared at 48 weeks. RESULTS: Fifty-one patients started with one of the two NNRTI-based regimens and 49 started with the triple nucleoside regimen (3-NRTI). After 48 weeks, more patients in the NNRTI regimens (76.5%) than in the 3-NRTI (51.1%) regimen achieved a HIV-1 RNA level below the limit of detection (<1.7 log10 copies/mL; p = .008). Time to change the antiretroviral regimen was shorter with 3-NRTI (median [range]: 234 [139-329] days) than with NNRTI (346 [0-756] days) (p = .0901). More withdrawals related to drug toxicity or intolerance occurred with the 3-NRTI-based regimen. CONCLUSION: In a routine clinical care setting, initial antiretroviral treatment with an NNRTI (nevirapine or efavirenz) plus zidovudine and lamivudine was virologically superior and safer than a 3-NRTI therapy (abacavir with the same NRTI backbone).

Adult↗