952 resultados para correlation coefficient
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BACKGROUND AND PURPOSE: There is high interindividual variability in the activity of drug-metabolizing enzymes catalysing the oxidation of oxycodone [cytochrome P450 (CYP) 2D6 and 3A], due to genetic polymorphisms and/or drug-drug interactions. The effects of CYP2D6 and/or CYP3A activity modulation on the pharmacokinetics of oxycodone remains poorly explored. EXPERIMENTAL APPROACH: A randomized crossover double-blind placebo-controlled study was performed with 10 healthy volunteers genotyped for CYP2D6 [six extensive (EM), two deficient (PM/IM) and two ultrarapid metabolizers (UM)]. The volunteers randomly received on five different occasions: oxycodone 0.2 mg x kg(-1) and placebo; oxycodone and quinidine (CYP2D6 inhibitor); oxycodone and ketoconazole (CYP3A inhibitor); oxycodone and quinidine+ketoconazole; placebo. Blood samples for plasma concentrations of oxycodone and metabolites (oxymorphone, noroxycodone and noroxymorphone) were collected for 24 h after dosing. Phenotyping for CYP2D6 (with dextromethorphan) and CYP3A (with midazolam) were assessed at each session. KEY RESULTS: CYP2D6 activity was correlated with oxymorphone and noroxymorphone AUCs and C(max) (-0.71 < Spearman correlation coefficient rhos < -0.92). Oxymorphone C(max) was 62% and 75% lower in PM than EM and UM. Noroxymorphone C(max) reduction was even more pronounced (90%). In UM, oxymorphone and noroxymorphone concentrations increased whereas noroxycodone exposure was halved. Blocking CYP2D6 (with quinidine) reduced oxymorphone and noroxymorphone C(max) by 40% and 80%, and increased noroxycodone AUC(infinity) by 70%. Blocking CYP3A4 (with ketoconazole) tripled oxymorphone AUC(infinity) and reduced noroxycodone and noroxymorphone AUCs by 80%. Shunting to CYP2D6 pathway was observed after CYP3A4 inhibition. CONCLUSIONS AND IMPLICATIONS: Drug-drug interactions via CYP2D6 and CYP3A affected oxycodone pharmacokinetics and its magnitude depended on CYP2D6 genotype.
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Background: Ventilator-associated pneumonia (VAP) is the most common hospital-acquired, life-threatening infection. Poor outcome and health-care costs of nosocomial pneumonia remain a global burden. Currently, physicians rely on their experience to discriminate patients with good and poor outcome. However, standardized prognostic measures might guide medical decisions in the future. Pancreatic stone protein (PSP)/regenerating protein (reg) is associated with inflammation, infection, and other disease-related stimuli. The prognostic value of PSP/reg among critically ill patients is unknown. The aim of this pilot study was to evaluate PSP/reg in VAP.Methods: One hundred one patients with clinically diagnosed VAP were assessed. PSP/reg was retrospectively analyzed using deep-frozen serum samples from VAP onset up to day 7. The main end point was death within 28 days after VAP onset.Results: Serum PSP/reg was associated with the sequential organ failure assessment score from VAP onset (Spearman rank correlation coefficient 0.49 P < .001) up to day 7. PSP/reg levels at VAP onset were elevated in nonsurvivors (n = 20) as compared with survivors (117.0 ng/mL [36.1-295.3] vs 36.3 ng/mL [21.0-124.0] P = .011). The areas under the receiver operating characteristic curves of PSP/reg to predict mortality/survival were 0.69 at VAP onset and 0.76 at day 7. Two PSP/reg cutoffs potentially allow for identification of individuals with a particularly good and poor outcome. Whereas PSP/reg levels below 24 ng/mL at YAP onset were associated with a good chance of survival, levels above 177 ng/mL at day 7 were present in patients with a very poor outcome.Conclusions: Serum PSP/reg is a biomarker related to organ failure and outcome in patients with VAP.
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BACKGROUND The demographic structure has a significant influence on the use of healthcare services, as does the size of the population denominators. Very few studies have been published on methods for estimating the real population such as tourist resorts. The lack of information about these problems means there is a corresponding lack of information about the behaviour of populational denominators (the floating population or tourist load) and the effect of this on the use of healthcare services. The objectives of the study were: a) To determine the Municipal Solid Waste (MSW) ratio, per person per day, among populations of known size; b) to estimate, by means of this ratio, the real population in an area where tourist numbers are very significant; and c) to determine the impact on the utilisation of hospital emergency healthcare services of the registered population, in comparison to the non-resident population, in two areas where tourist numbers are very significant. METHODS An ecological study design was employed. We analysed the Healthcare Districts of the Costa del Sol and the island of Menorca. Both are Spanish territories in the Mediterranean region. RESULTS In the two areas analysed, the correlation coefficient between the MSW ratio and admissions to hospital emergency departments exceeded 0.9, with p < 0.001. On the basis of MSW generation ratios, obtained for a control zone and also measured in neighbouring countries, we estimated the real population. For the summer months, when tourist activity is greatest and demand for emergency healthcare at hospitals is highest, this value was found to be double that of the registered population. CONCLUSION The MSW indicator, which is both ecological and indirect, can be used to estimate the real population in areas where population levels vary significantly during the year. This parameter is of interest in planning and dimensioning the provision of healthcare services.
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Aims To compare multidetector computed tomography (MDCT) with intravascular ultrasound (IVUS) and invasive quantitative coronary angiography (QCA) for assessment of coronary lesions in patients referred for suspected coronary artery disease (CAD). Methods and results We studied 57 patients (48 men; mean age: 63 +/- 10 years) who underwent 64-slice MDCT because of atypical chest pain, stable angina, or ECG abnormalities and were diagnosed with CAD. All patients subsequently underwent QCA and IVUS. We analyzed 102 coronary lesions using the three techniques. Measurements of luminal area stenosis and cross-sectional area by MDCT (72.9 +/- 7.0% and 4.5 +/- 1.8 mm(2), respectively) were in good agreement with those by IVUS [72.7 +/- 6.7% and 4.5 +/- 1.6 mm(2), respectively; Lin's concordance correlation coefficient r = 0.847; 95% confidence interval (CI) = 0.792-0.902 and r = 0.931; 95% CI = 0.906-0.956, respectively] but not QCA (r = 0.115; 95% CI = 0.040-0.189 and r = 0.433; 95% CI = 0.291-0.576, respectively). Plaque cross-sectional area and plaque volume measured by MDCT (12.4 +/- 3.8 mm(2) and 104.7 +/- 52.8 mu l, respectively) were in good agreement with those by IVUS (12.2 +/- 3.7 mm(2) and 102.8 +/- 54.1 mu l; r = 0.913; 95% CI = 0.880-0.945 and r = 0.979; 95% CI = 0.969-0.990, respectively). Remodeling index measurements by MDCT (1.22 +/- 0.22) were in good agreement with those by IVUS (r = 0.876; 95% CI = 0.831-0.922). Positive remodeling occurred in 63% of stenoses. Conclusion MDCT allows accurate noninvasive assessment of coronary stenosis, plaque burden and remodeling in patients referred for suspected CAD. Positive remodeling is a frequent finding in stable lesions. J Cardiovasc Med 12:122-130 (C) 2011 Italian Federation of Cardiology.
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Introduction: The quality of life assessment means investigating how patients perceive their disease. Malnutrition-specific characteristics make patients more vulnerable, so it is important to know how these factors impaction patients’ daily life. Aim: To assess the quality of life in malnourished patients who have had hospital admission, and to determine the relationship of the quality of life with age, body mass index, diagnosis of malnutrition, and dependency. Method: Multicenter transversal descriptive study in 106 malnourished patients after hospital admission. The quality of life (SF-12 questionnaire), BMI, functional independency (Barthel index), morbidity, and a dietary intake evaluation were assessed. The relationship between variables was tested by using the Spearman correlation coefficient Results: The patients of the present study showed a SF-12 mean of 38.32 points. The age was significantly correlated with the SF-12 (r= -0.320, p= 0.001). The BMI was correlated with the SF-12 (r= 0.251, p= 0.011) and its mental component (r= 0.289, p= 0.03). It was also reported a significant correlation between the Barthel index and the SF-12 (r= 0.370, p< 0.001). Conclusions: The general health perception in malnourished patients who have had a hospital admission was lower than the Spanish mean. Moreover, the quality of life in these patients is significantly correlated with age, BMI and functional independency.
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BACKGROUND: Prevention of cardiovascular disease (CVD) at the individual level should rely on the assessment of absolute risk using population-specific risk tables. OBJECTIVE: To compare the predictive accuracy of the original and the calibrated SCORE functions regarding 10-year cardiovascular risk in Switzerland. DESIGN: Cross-sectional, population-based study (5773 participants aged 35-74 years). METHODS: The SCORE equation for low-risk countries was calibrated based on the Swiss CVD mortality rates and on the CVD risk factor levels from the study sample. The predicted number of CVD deaths after a 10-year period was computed from the original and the calibrated equations and from the observed cardiovascular mortality for 2003. RESULTS: According to the original and calibrated functions, 16.3 and 15.8% of men and 8.2 and 8.9% of women, respectively, had a 10-year CVD risk > or =5%. Concordance correlation coefficient between the two functions was 0.951 for men and 0.948 for women, both P<0.001. Both risk functions adequately predicted the 10-year cumulative number of CVD deaths: in men, 71 (original) and 74 (calibrated) deaths for 73 deaths when using the CVD mortality rates; in women, 44 (original), 45 (calibrated) and 45 (CVD mortality rates), respectively. Compared to the original function, the calibrated function classified more women and fewer men at high-risk. Moreover, the calibrated function gave better risk estimates among participants aged over 65 years. CONCLUSION: The original SCORE function adequately predicts CVD death in Switzerland, particularly for individuals aged less than 65 years. The calibrated function provides more reliable estimates for older individuals.
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Background and purpose: There is high interindividual variability in the activity of drug-metabolizing enzymes catalysing the oxidation of oxycodone [cytochrome P450 (CYP) 2D6 and 3A], due to genetic polymorphisms and/or drug-drug interactions. The effects of CYP2D6 and/or CYP3A activity modulation on the pharmacokinetics of oxycodone remains poorly explored. Experimental approach: A randomized crossover double-blind placebo-controlled study was performed with 10 healthy volunteers genotyped for CYP2D6 [six extensive (EM), two deficient (PM/IM) and two ultrarapid metabolizers (UM)]. The volunteers randomly received on five different occasions: oxycodone 0.2 mg·kg−1 and placebo; oxycodone and quinidine (CYP2D6 inhibitor); oxycodone and ketoconazole (CYP3A inhibitor); oxycodone and quinidine+ketoconazole; placebo. Blood samples for plasma concentrations of oxycodone and metabolites (oxymorphone, noroxycodone and noroxymorphone) were collected for 24 h after dosing. Phenotyping for CYP2D6 (with dextromethorphan) and CYP3A (with midazolam) were assessed at each session. Key results: CYP2D6 activity was correlated with oxymorphone and noroxymorphone AUCs and Cmax (−0.71 < Spearman correlation coefficient ρs < −0.92). Oxymorphone Cmax was 62% and 75% lower in PM than EM and UM. Noroxymorphone Cmax reduction was even more pronounced (90%). In UM, oxymorphone and noroxymorphone concentrations increased whereas noroxycodone exposure was halved. Blocking CYP2D6 (with quinidine) reduced oxymorphone and noroxymorphone Cmax by 40% and 80%, and increased noroxycodone AUC∞ by 70%. Blocking CYP3A4 (with ketoconazole) tripled oxymorphone AUC∞ and reduced noroxycodone and noroxymorphone AUCs by 80%. Shunting to CYP2D6 pathway was observed after CYP3A4 inhibition. Conclusions and implications: Drug-drug interactions via CYP2D6 and CYP3A affected oxycodone pharmacokinetics and its magnitude depended on CYP2D6 genotype.
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PURPOSE: Self-administered questionnaires continue to be the most widely used type of physical activity assessment in epidemiological studies. However, test-retest reliability and validity of physical activity questionnaires have to be determined. In this study, three short physical activity questionnaires already used in Switzerland and the International Physical Activity Questionnaire (IPAQ) were validated. METHODS: Test-retest reliability was assessed by repeated administration of all questionnaires within 3 wk in 178 volunteers (77 women, 46.1+/-14.8 yr; 101 men 46.8+/-13.2 yr). Validity of categorical and continuous data was studied in a subsample of 35 persons in relation to 7-d accelerometer readings, percent body fat, and cardiorespiratory fitness. RESULTS: Reliability was fair to good with a Spearman correlation coefficient range of 0.43-0.68 for measures of continuous data and moderate to fair with Kappa values between 0.32 and 0.46 for dichotomous measures active/inactive. Total physical activity reported in the IPAQ and the Office in Motion Questionnaire (OIMQ) correlated with accelerometry readings (r=0.39 and 0.44, respectively). In contrast, correlations of self-reported physical data with percent body fat and cardiorespiratory fitness were low (r=-0.26-0.29). Participants categorized as active by the Swiss HEPA Survey 1999 instrument (HEPA99) accumulated significantly more days of the recommended physical activities than their inactive counterparts (4.4 and 2.7 d.wk, respectively, P<0.05). However, compared with accelerometer data, vigorous physical activities were overreported in investigated questionnaires. CONCLUSION: Collecting valid data on physical activity remains a challenging issue for questionnaire surveys. The IPAQ and the three other questionnaires are characterized to inform decisions about their appropriate use.
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The joint angles of multi-segment foot models have been primarily described using two mathematical methods: the joint coordinate system and the attitude vector. This study aimed to determine whether the angles obtained through these two descriptors are comparable, and whether these descriptors have similar sensitivity to experimental errors. Six subjects walked eight times on an instrumented walkway while the joint angles among shank, hindfoot, medial forefoot, and lateral forefoot were measured. The angles obtained using both descriptors and their sensitivity to experimental errors were compared. There was no overall significant difference between the ranges of motion obtained using both descriptors. However, median differences of more than 6° were noticed for the medial-lateral forefoot joint. For all joints and rotation planes, both descriptors provided highly similar angle patterns (median correlation coefficient: R>0.90), except for the medial-lateral forefoot angle in the transverse plane (median R=0.77). The joint coordinate system was significantly more sensitive to anatomical landmarks misplacement errors. However, the absolute differences of sensitivity were small relative to the joints ranges of motion. In conclusion, the angles obtained using these two descriptors were not identical, but were similar for at least the shank-hindfoot and hindfoot-medial forefoot joints. Therefore, the angle comparison across descriptors is possible for these two joints. Comparison should be done more carefully for the medial-lateral forefoot joint. Moreover, despite different sensitivities to experimental errors, the effects of the experimental errors on the angles were small for both descriptors suggesting that both descriptors can be considered for multi-segment foot models.
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We consider stock market contagion as a significant increase in cross-market linkages after a shock to one country or group of countries. Under this definition we study if contagion occurred from the U.S. Financial Crisis to the rest of the major stock markets in the world by using the adjusted (unconditional) correlation coefficient approach (Forbes and Rigobon, 2002) which consists of testing if average crossmarket correlations increase significantly during the relevant period of turmoil. We would not reject the null hypothesis of interdependence in favour of contagion if the increase in correlation only suggests a continuation of high linkages in all state of the world. Moreover, if contagion occurs, this would justify the intervention of the IMF and the suddenly portfolio restructuring during the period under study.
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The clinical demand for a device to monitor Blood Pressure (BP) in ambulatory scenarios with minimal use of inflation cuffs is increasing. Based on the so-called Pulse Wave Velocity (PWV) principle, this paper introduces and evaluates a novel concept of BP monitor that can be fully integrated within a chest sensor. After a preliminary calibration, the sensor provides non-occlusive beat-by-beat estimations of Mean Arterial Pressure (MAP) by measuring the Pulse Transit Time (PTT) of arterial pressure pulses travelling from the ascending aorta towards the subcutaneous vasculature of the chest. In a cohort of 15 healthy male subjects, a total of 462 simultaneous readings consisting of reference MAP and chest PTT were acquired. Each subject was recorded at three different days: D, D+3 and D+14. Overall, the implemented protocol induced MAP values to range from 80 ± 6 mmHg in baseline, to 107 ± 9 mmHg during isometric handgrip maneuvers. Agreement between reference and chest-sensor MAP values was tested by using intraclass correlation coefficient (ICC = 0.78) and Bland-Altman analysis (mean error = 0.7 mmHg, standard deviation = 5.1 mmHg). The cumulative percentage of MAP values provided by the chest sensor falling within a range of ±5 mmHg compared to reference MAP readings was of 70%, within ±10 mmHg was of 91%, and within ±15mmHg was of 98%. These results point at the fact that the chest sensor complies with the British Hypertension Society (BHS) requirements of Grade A BP monitors, when applied to MAP readings. Grade A performance was maintained even two weeks after having performed the initial subject-dependent calibration. In conclusion, this paper introduces a sensor and a calibration strategy to perform MAP measurements at the chest. The encouraging performance of the presented technique paves the way towards an ambulatory-compliant, continuous and non-occlusive BP monitoring system.
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Background: Non-invasive monitoring of respiratory muscle function is an area of increasing research interest, resulting in the appearance of new monitoring devices, one of these being piezoelectric contact sensors. The present study was designed to test whether the use of piezoelectric contact (non-invasive) sensors could be useful in respiratory monitoring, in particular in measuring the timing of diaphragmatic contraction.Methods: Experiments were performed in an animal model: three pentobarbital anesthetized mongrel dogs. The motion of the thoracic cage was acquired by means of a piezoelectric contact sensor placed on the costal wall. This signal is compared with direct measurements of the diaphragmatic muscle length, made by sonomicrometry. Furthermore, to assess the diaphragmatic function other respiratory signals were acquired: respiratory airflow and transdiaphragmatic pressure. Diaphragm contraction time was estimated with these four signals. Using diaphragm length signal as reference, contraction times estimated with the other three signals were compared with the contraction time estimated with diaphragm length signal.Results: The contraction time estimated with the TM signal tends to give a reading 0.06 seconds lower than the measure made with the DL signal (-0.21 and 0.00 for FL and DP signals, respectively), with a standard deviation of 0.05 seconds (0.08 and 0.06 for FL and DP signals, respectively). Correlation coefficients indicated a close link between time contraction estimated with TM signal and contraction time estimated with DL signal (a Pearson correlation coefficient of 0.98, a reliability coefficient of 0.95, a slope of 1.01 and a Spearman's rank-order coefficient of 0.98). In general, correlation coefficients and mean and standard deviation of the difference were better in the inspiratory load respiratory test than in spontaneous ventilation tests.Conclusion: The technique presented in this work provides a non-invasive method to assess the timing of diaphragmatic contraction in canines, using a piezoelectric contact sensor placed on the costal wall.
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Hirsutism, acne, alopecia, and oligo-amenorrhea are clinical expressions of hyperandrogenism, one of the most frequent endocrine disorders in women of reproductive age. Women referred to our endocrine clinics for skin symptoms of hyperandrogenism underwent a laboratory workup to evaluate hormone measurements and received antiandrogen therapy. We retrospectively analyzed the outcome of 228 consecutive patients investigated over 6 years.Patients with hirsutism had higher levels of androstenedione, dehydroepiandrosterone sulfate (DHEAS), and salivary testosterone; lower levels of sex hormone-binding globulin (SHBG); and a higher prevalence of oligo-amenorrhea than patients with alopecia, while patients with acne showed intermediate values. Hirsutism score correlated positively with androstenedione, DHEAS, and salivary testosterone, and correlated negatively with SHBG; salivary testosterone showed the highest correlation coefficient. Total testosterone was not significantly different among patients with hirsutism, alopecia, or acne, and did not significantly correlate with hirsutism score. Hirsutism and oligo-amenorrhea were the most sensitive symptoms of hyperandrogenism, and no androgenic parameter alone allowed us to identify all cases of hyperandrogenism.Patients of central European origin sought consultation with milder hirsutism scores than patients of southern European origin. There was, however, no difference in the clinical-biological correlation between these groups, arguing against differences in skin sensitivity to androgens.Polycystic ovary syndrome, defined as hyperandrogenism (hirsutism or elevated androgens) and oligo-amenorrhea, was diagnosed in 63 patients (27.6%), an underestimate compared with other reports that include systematic ovarian ultrasound studies. Neither pelvic ultrasound, used in a limited number of cases, nor the luteinizing hormone/follicle-stimulating hormone ratio helped to distinguish patients with polycystic ovary syndrome from the other diagnostic groups. These included hyperandrogenism (hirsutism or elevated androgens) and eumenorrhea (101 patients; 44.3%); normal androgens (acne or alopecia and eumenorrhea) (51 patients; 22.4%); isolated low SHBG (7 patients; 3.1%); nonclassical congenital adrenal hyperplasia (4 patients; 1.8% of total, 4.9% of patients undergoing cosyntropin stimulation tests); and ovarian tumor (2 patients; 0.9%).Ethinylestradiol and high-dose cyproterone acetate treatment lowered the hirsutism score to 53.5% of baseline at 1 year, and was also effective in treating acne and alopecia. The clinical benefit is ascribed to the peripheral antiandrogenic effect of cyproterone acetate as well as the hormone-suppressive effect of this combination. Salivary testosterone showed the most marked proportional decrease of all the androgens under treatment. Cost-effectiveness and tolerance of ethinylestradiol and high-dose cyproterone acetate compared well with other antiandrogenic drug therapies for hirsutism. The less potent therapy with spironolactone only, a peripheral antiandrogen without hormone-suppressive effect, was effective in treating isolated alopecia in patients with normal androgens.
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PURPOSE: To conduct a cross-cultural adaptation of the Core Outcome Measures Index (COMI) into French according to established guidelines. METHODS: Seventy outpatients with chronic low back pain were recruited from six spine centres in Switzerland and France. They completed the newly translated COMI, and the Roland Morris disability (RMQ), Dallas Pain (DPQ), adjectival pain rating scale, WHO Quality of Life, and EuroQoL-5D questionnaires. After ~14 days RMQ and COMI were completed again to assess reproducibility; a transition question (7-point Likert scale; "very much worse" through "no change" to "very much better") indicated any change in status since the first questionnaire. RESULTS: COMI whole scores displayed no floor effects and just 1.5% ceiling effects. The scores for the individual COMI items correlated with their corresponding full-length reference questionnaire with varying strengths of correlation (0.33-0.84, P < 0.05). COMI whole scores showed a very good correlation with the "multidimensional" DPQ global score (Rho = 0.71). 55 patients (79%) returned a second questionnaire with no/minimal change in their back status. The reproducibility of individual COMI 5-point items was good, with test-retest differences within one grade ranging from 89% for 'social/work disability' to 98% for 'symptom-specific well-being'. The intraclass correlation coefficient for the COMI whole score was 0.85 (95% CI 0.76-0.91). CONCLUSIONS: In conclusion, the French version of this short, multidimensional questionnaire showed good psychometric properties, comparable to those reported for German and Spanish versions. The French COMI represents a valuable tool for future multicentre clinical studies and surgical registries (e.g. SSE Spine Tango) in French-speaking countries.
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This study evaluated the acceptability, ceiling/floor effects, and the reliability of the instrument for measuring the Impact of the Disease on the Daily Life of Patients with Valvular Disease (IDCV) when applied to 135 patients with heart failure (HF). Acceptability was evaluated by the percentage of unanswered items and by the proportion of patients who responded to all items; the ceiling/floor effects by the percentage of patients who scored in the top of 10% best and worst results of the scale, respectively. Reliability was estimated by internal consistency (Cronbach's alpha coefficient) and stability of the measure (intraclass correlation coefficient - ICC). All patients responded to all items. Ceiling/floor effects evidenced were of moderate magnitude. The Cronbach's alpha was satisfactory for the majority of the domains and ICC> 0.90 in all the domains. The IDCV proved to be an easy to understand questionnaire, with evidence of reliability in patients with HF.