Biomedical subjects

Gabriel Baron

Publications and source records attributed to Gabriel Baron.

At least 19 recordsLinked to original sources

PubMed2006

Reporting of radiographic methods in randomised controlled trials assessing structural outcomes in rheumatoid arthritis.

BACKGROUND: Because an increasing number of clinical trials evaluating disease-modifying antirheumatic drugs in rheumatoid arthritis (RA) emphasise radiographic outcomes as a primary outcome, using a reproducible radiographic measure should be placed at a premium. AIM: To evaluate the reporting of radiographic methods in randomised trials assessing radiographic outcomes in RA. METHODS: Medline was searched for randomised controlled trials assessing radiographic outcomes published between January 1994 and December 2005 in general medical and specialty journals with a high impact factor. One reader extracted data (radiographic acquisition, assessment and reproducibility) using a standardised form. RESULTS: A total of 46 reports were included in the analysis. The mean (SD) methodological quality scores on the Jadad scale (range 0-5) and the Delphi list (0-9) were 2.9 (1.2) and 6.4 (1.3), respectively. Use of a standardised procedure for the acquisition of the radiographs was reported in 2 (4.3%) articles. 2 (4.3%) reports indicated that the quality of the radiographs was evaluated. In 65.2% of the reports, > or = 2 radiographic scores were used. Reporting of radiographic assessment was well detailed for number of readers (91.3%), information on readers (71.7%), blinding (91.4%) and how films were viewed (74.0%). The reproducibility of the reading was reported in 39.1% of the articles. CONCLUSION: The reporting of results of randomised controlled trials of radiographic outcomes in RA shows great variability in radiographic scores used. Reporting of radiographic methods could be improved upon, especially the acquisition procedure and the reproducibility of the reading.

Arthritis, Rheumatoid↗

PubMed2006

Feeling good rather than feeling better matters more to patients.

OBJECTIVE: To determine the most appropriate means to assess the response to treatment in terms of pain and functional impairment in a chronic rheumatic condition (knee osteoarthritis [OA]) and an acute rheumatic condition (rotator cuff syndrome [RCS]). METHODS: Two prospective studies were conducted consisting of 1,019 outpatients with knee OA and 271 patients with acute RCS. The minimal clinically important improvement and the patient acceptable symptom state were determined for knee OA pain using a visual analog scale, and for knee OA function using the Western Ontario and McMaster Universities Osteoarthritis Index function subscale; for acute RCS pain, a numeral rating scale was used, and the Neer function subscale was used for RCS function. RESULTS: The minimal clinically important improvement was shown to be the change required to achieve the patient acceptable symptom state, whatever the baseline level of symptom, the outcome (pain or function), or type of condition (chronic or acute). This acceptable state for pain was higher for chronic (27.0-36.4 across the baseline score) than acute (16.7-24.1) conditions. The level of functional impairment considered satisfactory by patients with knee OA was higher for more disabled patients (43.1) than for less disabled patients (20.4). CONCLUSION: Patients consider that they experienced an important improvement only if this improvement allowed them to achieve a state they consider satisfactory. The most appropriate means to assess the response to therapy seems to be to assess whether patients feel good (i.e., achieve the patient acceptable symptom state).

Aged↗

PubMed2006

General practitioners' fear-avoidance beliefs influence their management of patients with low back pain.

The objectives of this cross-sectional study conducted in primary care practice in France were to describe general practitioners' (GPs) fear-avoidance beliefs about low back pain (LBP), investigate the impact of these beliefs on their following guidelines for bed rest, physical activities, and sick leave, and uncover factors associated with GPs' fear-avoidance beliefs. A total of 864 GPs completed a 5-part self-administered questionnaire. Parts 1, 2, and 3 concerned demographic, professional data, and personal history of back pain, respectively. Part 4 dealt with GPs' education about LBP and practice for LBP. Part 5 assessed GPs' fear-avoidance beliefs on the Fear-Avoidance Beliefs Questionnaire (FABQ). GPs' mean age was 48.2+/-7.0 years, 80% were male, 88% had been practicing for more than 10 years, and 52% reported a previous personal episode of acute LBP. Forty-six percent had participated in an educational session on LBP during the last 3 years. Mean scores for the FABQ Phys and Work were 9.6+/-4.8 and 17.5+/-6.7, respectively. Sixteen percent of participants had high rating on the FABQ Phys (FABQ Phys score>14). FABQ Phys score was associated with recommendation of bed rest or rest during sick leave (p<0.0001) for acute LBP and less advice to maintain maximum bearable physical activities (p<0.001) for chronic LBP. FABQ Work score was associated with prescribing sick leave during painful periods (p<0.005) for acute LBP and less advice to maintain maximum bearable physical activities (p<0.001) for chronic LBP. GPs' fear-avoidance beliefs about LBP negatively influence their following guidelines concerning physical and occupational activities for patients with LBP.

Adult↗

PubMed2006

Quality of reporting of noninferiority and equivalence randomized trials.

CONTEXT: Noninferiority and equivalence trials aim to show that the experimental treatment is not clinically worse than (noninferior) or clinically similar to (equivalent) a control active treatment. These study objectives imply particular planning and analysis. OBJECTIVE: To assess the methodologic quality of reports of randomized controlled trials of noninferiority and equivalence. DESIGN: We searched MEDLINE and the Cochrane Central Register of Controlled Trials for reports of randomized controlled trials of noninferiority and equivalence hypotheses published between January 1, 2003, and December 31, 2004. MAIN OUTCOME MEASURES: Data extracted by use of a standardized form involved assessment of choice of noninferiority or equivalence margins, sample size calculation, sets of patients analyzed, method of statistical testing and reporting results, and conclusions. RESULTS: A total of 162 reports were included in the analysis (116 reports of noninferiority and 46 of equivalence). The margin defining noninferiority or equivalence was described in most reports (156 [96.3%]), with justification of the margin in only 33 (20.4%). Almost one quarter of the reports (35 [21.6%]) did not describe a sample size calculation, and an additional 11 (6.8%) did not take into account a prespecified noninferiority or equivalence margin. Less than half of the reports (69 [42.6%]) described both an intent-to-treat (ITT; all randomized patients are included in the analysis) or modified ITT (patients who never received treatment are excluded) and per-protocol (patients who did not complete the treatment are excluded) analysis, and only about half of those (39 [56.5%]) described both types of results. Results were displayed with confidence intervals in 136 reports (84.0%). Only 33 articles (20.3%) fulfilled reporting requirements specific to noninferiority and equivalence trials, 4 of them (12.1%) with misleading conclusions. CONCLUSIONS: Reporting of noninferiority and equivalence trials has important deficiencies: absence of noninferiority or equivalence margin, only an ITT (or a per-protocol) analysis performed, and results not adequately reported. Moreover, even for articles fulfilling these requirements, conclusions are sometimes misleading.

Bias↗

PubMed2006

Plasma brain natriuretic peptide and cardiac troponin I concentrations after adult cardiac surgery: association with postoperative cardiac dysfunction and 1-year mortality.

OBJECTIVE: The purpose of the present study was to evaluate the prognostic implications of perioperative B-type natriuretic peptide (BNP) and cardiac troponin I concentrations in patients undergoing cardiopulmonary bypass for cardiac surgery. DESIGN: Prospective observational study. SETTING: Biochemistry laboratory and surgical care unit in a university hospital. PATIENTS: A total of 92 consecutive patients undergoing elective coronary artery (43 patients) or valve surgery (49 patients). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: BNP and cardiac troponin I concentrations were measured before surgery (day 0), and at day 1 after surgery. Postoperative cardiac dysfunction was defined as low cardiac output or hemodynamic instability requiring inotropic support for >24 hrs or congestive heart failure until day 5. One-year survival was also evaluated. Univariate and multivariate analyses were performed. An important BNP secretion was systematically observed after cardiac surgery. Independent predictors of cardiac dysfunction were preoperative New York Health Association class and BNP and cardiac troponin I concentrations measured at day 1. Patients with an elevation of both markers have a 12-fold increased risk of postoperative heart failure. The use of both markers in combination predicted better postoperative heart failure than each one separately. Age, low preoperative left ventricular ejection fraction, and elevated BNP at day 1 (>352 pg/mL) were associated with an increased mortality rate at 1 yr. In multivariate analysis, only left ventricular ejection fraction was significantly associated with 1-yr survival. CONCLUSIONS: Postoperative plasma BNP and cardiac troponin I levels are independent predictors of postoperative cardiac dysfunction after cardiac surgery. Simultaneous measurement of BNP and cardiac troponin I improve the risk assessment of postoperative cardiac dysfunction. However, the association between BNP levels and 1-yr outcome was no longer significant after adjustment on left ventricular ejection fraction.

Aged↗

PubMed2006

Inhibition of anti-tuberculosis T-lymphocyte function with tumour necrosis factor antagonists.

Reactivation of latent Mycobacterium tuberculosis (Mtb) infection is a major complication of anti-tumour necrosis factor (TNF)-alpha treatment, but its mechanism is not fully understood. We evaluated the effect of the TNF antagonists infliximab (Ifx), adalimumab (Ada) and etanercept (Eta) on anti-mycobacterial immune responses in two conditions: with ex vivo studies from patients treated with TNF antagonists and with the in vitro addition of TNF antagonists to cells stimulated with mycobacterial antigens. In both cases, we analysed the response of CD4+ T lymphocytes to purified protein derivative (PPD) and to culture filtrate protein (CFP)-10, an antigen restricted to Mtb. The tests performed were lymphoproliferation and immediate production of interferon (IFN)-gamma. In the 68 patients with inflammatory diseases (rheumatoid arthritis, spondylarthropathy or Crohn's disease), including 31 patients with a previous or latent tuberculosis (TB), 14 weeks of anti-TNF-alpha treatment had no effect on the proliferation of CD4+ T lymphocytes. In contrast, the number of IFN-gamma-releasing CD4+ T lymphocytes decreased for PPD (p < 0.005) and CFP-10 (p < 0.01) in patients with previous TB and for PPD (p < 0.05) in other patients (all vaccinated with Bacille Calmette-Guérin). Treatments with Ifx and with Eta affected IFN-gamma release to a similar extent. In vitro addition of TNF antagonists to CD4+ T lymphocytes stimulated with mycobacterial antigens inhibited their proliferation and their expression of membrane-bound TNF (mTNF). These effects occurred late in cultures, suggesting a direct effect of TNF antagonists on activated mTNF+ CD4+ T lymphocytes, and Ifx and Ada were more efficient than Eta. Therefore, TNF antagonists have a dual action on anti-mycobacterial CD4+ T lymphocytes. Administered in vivo, they decrease the frequency of the subpopulation of memory CD4+ T lymphocytes rapidly releasing IFN-gamma upon challenge with mycobacterial antigens. Added in vitro, they inhibit the activation of CD4+ T lymphocytes by mycobacterial antigens. Such a dual effect may explain the increased incidence of TB in patients treated with TNF antagonists as well as possible differences between TNF antagonists for the incidence and the clinical presentation of TB reactivation.

Adalimumab↗

PubMed2005

Decision-making in elderly patients with severe aortic stenosis: why are so many denied surgery?

AIMS: To analyse decision-making in elderly patients with severe, symptomatic aortic stenosis (AS). METHODS AND RESULTS: In the Euro Heart Survey on valvular heart disease, 216 patients aged > or =75 had severe AS (valve area < or =0.6 cm(2)/m(2) body surface area or mean gradient > or =50 mmHg) and angina or New York Heart Association class III or IV. Patient characteristics were analysed according to the decision to operate or not. A decision not to operate was taken in 72 patients (33%). In multivariable analysis, left ventricular (LV) ejection fraction [OR = 2.27, 95% CI (1.32-3.97) for ejection fraction 30-50, OR = 5.15, 95% CI (1.73-15.35) for ejection fraction < or =30 vs. >50%, P = 0.003] and age [OR = 1.84, 95% CI (1.18-2.89) for 80-85 years, OR=3.38, 95% CI (1.38-8.27) for > or =85 vs. 75-80 years, P = 0.008] were significantly associated with the decision not to operate; however, the Charlson comorbidity index was not [OR = 1.72, 95% CI (0.83-3.50), P = 0.14 for index > or =2 vs. <2]. Neurological dysfunction was the only comorbidity significantly linked with the decision not to operate. CONCLUSION: Surgery was denied in 33% of elderly patients with severe, symptomatic AS. Older age and LV dysfunction were the most striking characteristics of patients who were denied surgery, whereas comorbidity played a less important role.

Age Factors↗

PubMed2005

Reporting of harm in randomized, controlled trials of nonpharmacologic treatment for rheumatic disease.

BACKGROUND: Reports of clinical trials usually emphasize benefits and give less attention to harms. PURPOSE: To compare the reporting of harm in trials of pharmacologic and nonpharmacologic treatment. DATA SOURCES: MEDLINE and the Cochrane Central Register of Controlled Trials. STUDY SELECTION: Reports of randomized, controlled trials assessing treatment of rheumatic disease that were published between January 1999 and January 2005. DATA EXTRACTION: A standardized abstraction form was used to extract data. DATA SYNTHESIS: 193 articles were analyzed. After adjustment for medical area, sample size, funding source, and multicenter trials, data on harm were more often described in pharmacologic treatment reports than in nonpharmacologic treatment reports in reporting adverse events (odds ratio, 5.2 [95% CI, 2.1 to 12.9]), reporting withdrawals due to adverse events (odds ratio, 4.6 [CI, 2.0 to 10.9]), reporting severity (odds ratio, 3.7 [CI, 1.5 to 9.1]), and allocating space for describing harm (odds ratio, 1.6 [CI, 1.2 to 2.3]). LIMITATIONS: Extrapolating results to trials in areas other than rheumatic disease is questionable. CONCLUSIONS: The lack of reporting harm in trials assessing nonpharmacologic treatment in rheumatic disease is an important barrier to evaluating the benefit-harm balance of nonpharmacologic treatments.

Antirheumatic Agents↗

PubMed2005

Impact of ultrasound imaging on local corticosteroid injections of symptomatic ankle, hind-, and mid-foot in chronic inflammatory diseases.

OBJECTIVE: To assess the impact of ultrasonography (US) on local corticosteroid (CS) injections of painful ankle, hindfoot, and midfoot in chronic inflammatory diseases. METHODS: Consecutive patients with chronic rheumatic diseases admitted to the hospital for local CS injections of painful ankle, hindfoot, or midfoot were enrolled in this study. Clinical and radiographic evaluation was performed by the physician in charge of CS injections, and US examination was performed by an independent examiner blinded to the clinical and radiologic findings. According to a randomized weekly-periods design, the physician planned CS injections either aware (G1 group) or unaware (G2 group) of US results. In the latter case, he was nonetheless informed of US results after he had performed the injections. Impact of this information on the treatment planning was assessed in all cases. Prognostic impact of US was also evaluated by comparing the change in global assessment of efficacy of CS injections, in activity of the disease, and in the Western Ontario and McMaster Universities (WOMAC) subscales after 1 and 3 months, between G1 and G2 groups. RESULTS: The knowledge of US findings led the physician to change his decision of local CS injections in 56 (82%) of 68 patients studied. Among 1,131 assessed sites, by clinical, radiographic, and US evaluation, injection was cancelled in 37 (15%) of 242 proposed sites, whereas it was decided in 74 (8%) additional sites. After 1 month, there was an improvement in G1 as compared with G2 groups. The mean +/- SD change in WOMAC physical function subscale was 15.6 +/- 17.5 in G1 versus 8 +/- 13 in G2 (P = 0.0305). After 3 months, only the global assessment of efficacy of CS injections was statistically greater in G1 than in G2 group (P = 0.0170). CONCLUSION: US frequently led the physician to change his diagnosis of inflammatory lesions in painful foot, and consequently his planning of CS injections. Moreover, US could improve the response to local treatment.

Arthritis, Rheumatoid↗

PubMed2005

Effects of intravenous polymaltose iron on oxidant stress and non-transferrin-bound iron in hemodialysis patients.

BACKGROUND: The use of intravenous iron to correct anemia in end-stage renal diseases (ESRD) has been suspected of catalyzing the production of activated oxygen species and promoting oxidative damage. We investigated the pro-oxidative potential of injected iron in hemodialysis patients. METHODS: In study A, 65 patients with ESRD were studied. 20 patients received weekly infusions of iron polymaltose (maltofer), whereas 45 patients had been off iron therapy for more than 2 months. In study B, 12 patients were investigated during two consecutive hemodialysis sessions, one session without and one session with infusion of 100 mg of maltofer over 4 h. Serum iron status, non-transferrin-bound iron (NTBI) and markers of oxidative stress were studied in blood samples from these patients. RESULTS: In study A, NTBI was detected in 41% of the patients and the proportion of NTBI-positive patients was the same whether or not they received iron therapy. In study B, the serum iron and transferrin saturation index increased during iron infusion and NTBI transiently appeared in some patients but markers of oxidative stress were not significantly affected. CONCLUSION: Although ESRD patients have a high prevalence of NTBI in their serum, no correlation could be established between the presence of NTBI and an increased oxidative stress. The slow infusion of maltofer does not promote a significant increase in the plasma concentration of oxidative stress markers. It may therefore be considered as a safe complement to erythropoietin therapy.

Adult↗

PubMed2005

Violation of the intent-to-treat principle and rate of missing data in superiority trials assessing structural outcomes in rheumatic diseases.

OBJECTIVE: To evaluate the methodologic quality of and identify methodologic issues in superiority trials assessing structural outcomes in rheumatic diseases. METHODS: We searched Medline and the Cochrane Central Register of Controlled Trials for reports of randomized controlled trials assessing structural outcomes in osteoarthritis (OA), rheumatoid arthritis (RA), and osteoporosis (OP) published between January 1994 and December 2003 in high-impact factor general medical and specialty journals. One reader extracted data (quality assessment, intent-to-treat analysis [ITT analysis], rate of missing data, and methods of handling missing data), using a standardized form. RESULTS: A total of 81 reports were included in the analysis (37 on OP, 34 on RA, and 10 on OA). The mean +/- SD methodologic quality scores on the Jadad scale (possible range 0-5) and the Delphi list (possible range 0-9) were 2.9 +/- 1.2 and 6.4 +/- 1.3, respectively. Although it was reported in 54 articles (66.7%) that the analysis was done on an ITT basis, full ITT analysis was performed in only 6 of the studies (7.4%), modified ITT analysis in 11 (13.6%), and case-complete analysis in 48 (59.3%); the analysis was unclear in 16 articles (19.8%). The rate of missing data on structural outcomes could be determined in only 63 articles (77.8%) and was >20% in approximately one-third of these reports. Methods for handling missing data on structural outcomes were described in 19 articles (23.5%) and were, in general, inappropriate. CONCLUSION: Lack of ITT analysis and a high rate of missing data in superiority trials assessing structural outcomes may bias results from such trials. Our recommendations for improving these shortcomings may help researchers plan, analyze, and report the results of such trials.

Arthritis, Rheumatoid↗

PubMed2005

Population pharmacokinetic analysis of indinavir in HIV-infected patient treated with a stable antiretroviral therapy.

The objectives of this study were to build a population pharmacokinetic model that describe plasma concentrations of indinavir in human immunodeficiency virus (HIV)-infected patients with sustained virological response under a stable antiretroviral combination, and to characterize the effect of covariates and co-medications on indinavir pharmacokinetics. Data were obtained from 45 patients who received different dosages of indinavir: either indinavir alone t.i.d. (mostly 800 mg), either indinavir b.i.d. (mostly 800 mg) with a booster dose of 100 mg of ritonavir. Patients were required to have a baseline plasma HIV RNA <200 copies/mL and to have unchanged antiretroviral treatment for 6 months. Indinavir concentrations were measured at a first visit (one sample before drug administration and five after) and at a second visit 3 months later (before and 1 or 3 h after drug administration). A one-compartment model with first-order absorption and first-order elimination best described indinavir pharmacokinetics. For patients treated with indinavir alone, absorption rate constant was estimated to be 0.43/h, and oral clearance Cl/F was 33 L/h. For patients treated with indinavir plus ritonavir these estimates were 0.25/h and 19 L/h, respectively. Cl/F was found to increase by 1.45-fold in men and by 1.18-fold in patients also receiving zidovudine. Oral volume of distribution (V/F) was 24 L. The inter-individual and intra-individual variability were 117 and 205% for V/F, 42 and 58% for Cl/F, respectively. This population analysis in patients with sustained virological response, quantified the effect of ritonavir on the absorption rate constant and on the clearance of indinavir, showed an increase of Cl/F in men and can be used to draw reference curve for therapeutic drug monitoring.

Adult↗

PubMed2004

Leukoaraiosis and mobility decline: a high resolution magnetic resonance imaging study in older people with mild cognitive impairment.

Patterns of leukoaraiosis were analyzed on both T2-weighted fast fluid-attenuated inversion-recovery and 3D T1-weighted sequences in 23 community-dwelling older subjects with mild cognitive impairment. Mobility assessment had allowed their classification into higher and lower mobility groups (P<0.0001). Lower mobility appeared correlated with frontal subependymal lesions (P=0.0005). The absence of marked ventriculomegaly, any thick caps, deep white matter lesions curved along the ventricles bodies, large deep white matter lesions, deep grey matter leukoaraiosis was an hallmark of the higher mobility group (P<0.0001). High resolution MRI demonstrated regular patterns of the subependymal lesions and detected perivascular distribution in other forms of leukoaraiosis. It suggests that the underlying mechanism of mobility decline in the elderly may be impairment of cerebrospinal fluid dynamics with cerebral small vessel disease.

Aged↗

PubMed2004

Inefficacy of infliximab in primary Sjögren's syndrome: results of the randomized, controlled Trial of Remicade in Primary Sjögren's Syndrome (TRIPSS).

OBJECTIVE: There is no effective treatment for patients with primary Sjögren's syndrome (SS). Since tumor necrosis factor alpha (TNF alpha) could be a key element in the pathogenesis of primary SS, we conducted a multicenter, randomized, double-blind, placebo-controlled trial to evaluate the effect of infliximab in primary SS. METHODS: A total of 103 patients with primary SS were randomly assigned to receive infliximab infusions (5 mg/kg) or placebo at weeks 0, 2, and 6 and were followed up for 22 weeks. All patients fulfilled the new American-European Consensus Group criteria for SS and had active disease as assessed by values >50 mm on 2 of 3 visual analog scales (VAS) (0-100 mm) that evaluated joint pain, fatigue, and buccal, ocular, skin, vaginal, or bronchial dryness. A favorable overall response was defined as the patient having > or =30% improvement between weeks 0 and 10 in the values on 2 of the 3 VAS. Secondary end points were values on each VAS separately, the number of tender and swollen joints, the basal salivary flow rate, results of the Schirmer test for lacrimal gland function, the focus score on labial salivary gland biopsy, the level of C-reactive protein, and the erythrocyte sedimentation rate evaluated at weeks 0, 10, and 22, as well as quality of life evaluated by use of the generic Short Form 36 questionnaire administered at weeks 0, 10, and 22. RESULTS: At week 10, 26.5% of patients receiving placebo and 27.8% of patients treated with infliximab had a favorable overall response (P = 0.89), and at week 22, 20.4% of the placebo group and 16.7% of the infliximab group had a favorable response (P = 0.62). In addition, the 2 groups did not differ in any of the secondary end points over the 22 weeks of the trial. Severe adverse events reported in the infliximab group did not differ from those observed in previous studies. CONCLUSION: This randomized, double-blind, placebo-controlled study of an anti-TNF agent did not show any evidence of efficacy of infliximab in primary SS.

Aged↗

PubMed2004

Temporal trends in percutaneous mitral commissurotomy over a 15-year period.

AIMS: To evaluate temporal trends in percutaneous mitral commissurotomy (PMC) in terms of changes in patient characteristics and their impact on immediate results. METHODS AND RESULTS: From 1986 to 2001, PMC was indicated in 2773 consecutive patients. Patient characteristics and results were compared each year and linear trends were analysed. There were significant trends toward an increase in mean age (p <0.0001) and the proportion of patients in NYHA class I or II before PMC (p <0.0001), and toward a decrease in the proportion of atrial fibrillation (p <0.0002) and favourable valve anatomy (p < 0.0001), but no change in initial valve area ( p < 0.22). Technical failure occurred in 32 patients (1.2%). The failure rate decreased from 6.4% in 1986-1987 to 3.6% in 1988 and was less than 1.5% from then on (p < 0.0001). The frequency of good immediate results (valve area > or =1.5 cm(2) without regurgitation >2/4) did not differ over the years ( p < 0.22), with a mean rate of 89.5% of effective procedures and 88.5% of all procedures. CONCLUSION: Over this 15-year period, candidates for PMC became older and had a less favourable anatomy, but underwent PMC at an earlier functional stage. The stability of the results, despite the less favourable characteristics, may be related to the role of experience in improving the technique and patient selection.

Adult↗

PubMed2004

The methods for handling missing data in clinical trials influence sample size requirements.

OBJECTIVE: Results of studies estimating osteoarthritis progression may be affected by missing values. In clinical trials assessing disease-modifying osteoarthritis drugs, sample sizes should be calculated using close estimates of outcome variables. STUDY DESIGN AND SETTING: Supposing a two-parallel group design in hip osteoarthritis clinical trials, we estimated sample sizes using the joint space width (JSW), number of patients with JSW progression >0.5 mm (JSN), time to total hip arthroplasty (THA), and time to JSN or THA using several approaches to deal with missing data. RESULTS: Three-year clinical trials testing a treatment effect of 50%, with a power of 80%, could require sample sizes of 121 patients for JSW, 57 for JS progression using multiple imputation for handling missing values; 200 for THA; and 47 for JSN or THA. These numbers vary greatly depending on the approach chosen for handling missing data. CONCLUSIONS: These results can help investigators plan clinical trials to select the primary outcome and a priori specify the way missing data will be handled.

Aged↗

PubMed2004

Social and personal consequences of disability in adults with hip and knee arthroplasty. A French national community based survey.

OBJECTIVE: To describe and compare participation restrictions and environmental factors of persons with and without hip or knee arthroplasty in a national community based survey: the Handicap, Disability, Dependence Survey. METHODS: During the 1999 French Census, a screening questionnaire was proposed to 417,500 persons, for which the response rate was 86%. A stratified random sample with an overrepresentation of disabled persons was performed to constitute the selected population. A computer assisted interview was proposed to 21,760 persons, with a 78% response rate. Chronic conditions, impairment, disability, participation restrictions, and the description of environmental factors were ascertained from the subjects' reports. RESULTS: The hip and knee arthroplasty group was estimated at 691,000 persons in the French population. Although reporting a higher level of disability, this population did not report more participation restrictions than the general population in terms of their economic situation, housing, social relationships, and holidays. Moreover, when comparing environmental factors, this population reported better housing accessibility, more assistive devices (OR 5.2, 95% CI 3.7-7.2), specific fittings (OR 2.9, 95% CI 2.0-4.2), and helpers (OR 1.8, 95% CI 1.3-2.5). These environmental factors may have compensated for the higher level of disability. Nevertheless, individuals with hip and knee arthroplasty reported more disadvantages when moving within their environment (OR 2.1, 95% CI 1.5-2.9). CONCLUSION: This study provides a detailed description based on a national random sample of participation restrictions and environmental factors of adults with hip and knee arthroplasty.

Activities of Daily Living↗

PubMed2003

A prospective survey of patients with valvular heart disease in Europe: The Euro Heart Survey on Valvular Heart Disease.

AIMS: To identify the characteristics, treatment, and outcomes of contemporary patients with valvular heart disease (VHD) in Europe, and to examine adherence to guidelines. METHODS AND RESULTS: The Euro Heart Survey on VHD was conducted from April to July 2001 in 92 centres from 25 countries; it included prospectively 5001 adults with moderate to severe native VHD, infective endocarditis, or previous valve intervention. VHD was native in 71.9% of patients and 28.1% had had a previous intervention. Mean age was 64+/-14 years. Degenerative aetiologies were the most frequent in aortic VHD and mitral regurgitation while most cases of mitral stenosis were of rheumatic origin. Coronary angiography was used in 85.2% of patients before intervention. Of the 1269 patients who underwent intervention, prosthetic replacement was performed in 99.0% of aortic VHD, percutaneous dilatation in 33.9% of mitral stenosis, and valve repair in 46.5% of mitral regurgitation; 31.7% of patients had > or =1 associated procedure. Of patients with severe, symptomatic, single VHD, 31.8% did not undergo intervention, most frequently because of comorbidities. In asymptomatic patients, accordance with guidelines ranged between 66.0 and 78.5%. Operative mortality was <5% for single VHD. CONCLUSIONS: This survey provides unique contemporary data on characteristics and management of patients with VHD. Adherence to guidelines is globally satisfying as regards investigations and interventions.

Adult↗