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Jean-Jacques Parienti

Publications and source records attributed to Jean-Jacques Parienti.

17 recordsLinked to original sources
PubMed2006

Cluster-crossover design: a method for limiting clusters level effect in community-intervention studies.

The cluster-crossover design can be used for clinical trials comparing two or more interventions in a naturally formed study population, i.e. a cluster. This design differs from that of a crossover study, in that the treatment sequence is allocated at the cluster level. A cluster-crossover study can thus be considered as a cluster-randomized controlled study with additional periodic cluster-randomization(s) or treatment permutation(s) during the study. The data must be analyzed with hierarchical models with random effects in order to allow for different outcome probabilities in each period, cluster and cluster-period. Original data from two published field studies of hospital infection control based on this design are used here to illustrate the impact of different statistical models on the interpretation of the results.

Clinical Trials as Topic↗
PubMed2006

Methodological standards in non-inferiority AIDS trials: moving from adherence to compliance.

BACKGROUND: The interpretation of the results of active-control trials regarding the efficacy and safety of a new drug is important for drug registration and following clinical use. It has been suggested that non-inferiority and equivalence studies are not reported with the same quantitative rigor as superiority studies. METHODS: Standard methodological criteria for non-inferiority and equivalence trials including design, analysis and interpretation issues were applied to 18 recently conducted large non-inferiority (15) and equivalence (3) randomized trials in the field of AIDS antiretroviral therapy. We used the continuity-corrected non-inferiority chi-square to test 95% confidence interval treatment difference against the predefined non-inferiority margin. RESULTS: The pre-specified non-inferiority margin ranged from 10% to 15%. Only 4 studies provided justification for their choice. 39% of the studies (7/18) reported only intent-to-treat (ITT) analysis for the primary endpoint. When on-treatment (OT) and ITT statistical analyses were provided, ITT was favoured over OT for results interpretation for all but one study, inappropriately in this statistical context. All but two of the studies concluded there was "similar" efficacy of the experimental group. However, 9/18 had inconclusive results for non-inferiority. CONCLUSION: Conclusions about non-inferiority should be drawn on the basis of the confidence interval analysis of an appropriate primary endpoint, using the predefined criteria for non-inferiority, in both OT and ITT, in compliance with the non-inferiority and equivalence CONSORT statement. We suggest that the use of the non-inferiority chi-square test may provide additional useful information.

Acquired Immunodeficiency Syndrome↗
PubMed2006

Fluoroquinolone use and methicillin-resistant Staphylococcus aureus isolation rates in hospitalized patients: a quasi experimental study.

BACKGROUND: We investigated the possible association between fluoroquinolone use and the rate of methicillin-resistant Staphylococcus aureus (MRSA) recovery from consecutive hospitalized patients. METHODS: We conducted a nonrandomized, prospective, controlled interventional "fluoroquinolone-free" study at 4 large teaching hospitals in northwest France, catering to a total of 5,882,600 persons. During the intervention period (January through December 2001), fluoroquinolone use was prohibited at 1 of the 4 hospitals (Caen Hospital), unless no effective alternative was available. Three university hospitals were used as controls because they had similar preintervention rates of MRSA. RESULTS: During the intervention period (2001), the annual rate of fluoroquinolone use decreased from 54 to 5 defined daily doses per 1000 patients per day at Caen Hospital and remained stable in the control hospitals. At the end of the intervention, the rate of MRSA isolation was significantly lower at Caen Hospital than at the control hospitals (353 [32.3%] of 1093 S. aureus isolates were MRSA, compared with 2495 [36.8%] of 6787 isolates; odds ratio, 0.82; 95% confidence interval, 0.69-0.99; P=.036), as determined on the basis of a marginal model that took into account within-hospital clustering. In a before-after time series analysis, compared with forecasted rates, there was a significant downward trend in observed monthly rates of MRSA isolation at Caen Hospital at the end of the intervention. CONCLUSION: This quasi experimental study confirms the association between fluoroquinolone use and MRSA isolation among hospitalized patients.

Anti-Bacterial Agents↗
PubMed2006

Epidemiology and clinical outcome of virus-positive respiratory samples in ventilated patients: a prospective cohort study.

INTRODUCTION: Respiratory viruses are a major cause of respiratory tract infections. The prevalence of a virus-positive respiratory sample and its significance in patients requiring mechanical ventilation remain unknown. METHODS: We conducted a cohort study in all consecutive adults ventilated for more than 48 hours admitted to a 22-bed medical intensive care unit during a 12-month period. Respiratory samples at the time of intubation were assessed by culture, by indirect immunofluorescence assay or by molecular methods in systematic tracheobronchial aspirates. Patients with a virus-negative respiratory sample at the time of intubation were considered unexposed and served as the control group. RESULTS: Forty-five viruses were isolated in 41/187 (22%) patients. Rhinovirus was the most commonly isolated virus (42%), followed by herpes simplex virus type 1 (22%) and virus influenza A (16%). In multivariate analysis controlling for the Acute Pathophysiology and Chronic Health Evaluation II score, patients with respiratory disorder at admission (adjusted odds ratio, 2.1; 95% confidence interval, 0.8-5.1; P = 0.12), with chronic obstructive pulmonary disease/asthma patients (adjusted odds ratio, 3.0; 95% confidence interval, 1.3-6.7; P = 0.01) and with admission between 21 November and 21 March (adjusted odds ratio, 2.8; 95% confidence interval, 1.3-5.9; P = 0.008) were independently associated with a virus-positive sample. Among the 122 patients admitted with respiratory disorder, a tracheobronchial aspirate positive for respiratory viruses at the time of intubation (adjusted hazard ratio, 0.273; 95% confidence interval, 0.096-0.777; P < 0.006) was independently associated with better survival, controlling for the Simplified Acute Physiology Score II and admission for cardiogenic shock or cardiac arrest. Among the remaining 65 patients, a virus-positive sample on intubation did not predict survival. CONCLUSION: We confirmed the pathogenic role of respiratory viruses in the intensive care unit, particularly rhinovirus. We suggest, however, that the prognostic value of virus-associated respiratory disorder is better than that of other causes of respiratory disorder.

Aged↗
PubMed2005

The attributable mortality of acute renal failure in critically ill patients with liver cirrhosis.

OBJECTIVE: To determine outcome and mortality risk related to acute renal failure (ARF) in critically ill patients with cirrhosis. DESIGN AND SETTING: A retrospective cohort analysis and two independent case-control analyses in a medical ICU. PATIENTS: 41 and 32 patients who developed mild and severe ARF, respectively, matched (1:2 ratio) with cirrhotic patients without ARF during their ICU stay. MEASUREMENTS AND RESULTS: Cirrhotic patients with ARF had higher MELD, APACHE II, and SOFA scores at baseline that those without ARF. They had more respiratory failure and cardiovascular failure during ICU stay, longer stay in ICU, and a greater crude hospital mortality rate (65% vs. 32%). Multivariate survival analysis identified ARF (hazard ratio, HR, 4.1), alcohol abuse or dependency, and severe sepsis or septic shock as independent predictors of death. In case-control studies both mild and severe ARF were independently associated with mortality (HR, 2.6, and 4.2, respectively). Cirrhotic patients with mild ARF patients had a higher risk of death than those without ARF (relative risk, RR, 2.0). Severe ARF was associated with an increase matched risk of death (RR 2.6), higher mortality of 51%, and higher risk-adjusted mortality rate (2.1 vs. 0.9). CONCLUSIONS: ICU patients with liver cirrhosis still have a high crude mortality. In this specific population ARF is associated with an excess mortality, depending on the severity of renal dysfunction.

Acute Kidney Injury↗
PubMed2005

Impact of anemia on outcome in critically ill patients with severe acute renal failure.

OBJECTIVE: To evaluate the prognostic value of hemoglobin levels in critically ill patients with acute renal failure (ARF) requiring dialysis. DESIGN AND SETTING: A prospective observational cohort study in two adult medical ICUs. PATIENTS: 206 consecutive patients with ARF who required dialysis. Overall 28-day mortality was 48%. MEASUREMENTS AND RESULTS: At ICU admission mean hemoglobin level was 9.1+/-2.1 g/dl. By ROC curve analysis the threshold value of hemoglobin with the highest sensibility/specificity was 9 g/dl. At baseline 63% of patients had anemia, defined as initial hemoglobin below 9 g/dl. Kaplan-Meier analysis showed that these patients had lower survival rate than those with hemoglobin above 9 g/dl. By multivariable analysis three factors were independently associated with 28-day death: hemoglobin lower than 9 g/dl (adjusted odds ratio 2.4, 95% CI 1.1-5.2), age, and SOFA score. Based on age and SOFA a matched cohort analysis of 67 pairs of ARF patients with or without anemia found similar results regarding the negative impact of anemia on outcome. Finally, a multivariable logistic regression analysis on matched cohort identified hemoglobin level below 9 g/dl (adjusted odds ratio 1.32, 95%CI 1.15-1.46), continuous renal replacement therapy, and vasoactive therapy as independent predictors of 28-day death. CONCLUSIONS: These results suggest that initial hemoglobin level could be helpful in identifying patients with ARF requiring dialysis at high risk of death.

Acute Kidney Injury↗
PubMed2005

Nosocomial viral ventilator-associated pneumonia in the intensive care unit: a prospective cohort study.

OBJECTIVE: To determine the incidence, risk factors, and clinical relevance of viral ventilator-associated pneumonia (VAP) in an adult intensive care unit (ICU). DESIGN: Prospective observational study. SETTING: A 22-bed adult medical ICU in a university hospital. PATIENTS: All consecutive adult patients ventilated more than 48 h in a 9-month period including regular seasonal viral infections. INTERVENTIONS: A tracheobronchial aspirate upon enrollment and at the time of VAP suspicion. MEASUREMENTS AND RESULTS: All respiratory specimens were tested in culture, indirect immunofluorescence assay, and PCR or RT-PCR for virological assessment. Patients were followed until ICU discharge or death. One hundred thirty-nine patients were included. Upon enrollment, a respiratory virus was detected in the tracheobronchial aspirate in 25% of patients (35 of 139). The incidence of VAP, defined according to clinical daily evaluation, was 28% (39 of 139 patients). A bacteria was documented in 74% of cases, whereas no case of a causative viral infection was encountered among VAP patients; however, herpes simplex virus type-1 (HSV 1) infection was detected in respiratory specimens of 31% of VAP (12 of 39). CONCLUSIONS: We found a high incidence of HSV-1 infection in VAP patients; however, nosocomial viral VAP is likely to be rare in ICU, as assessed by the absence of respiratory virus-induced VAP identified in this prospective cohort study.

Adult↗
PubMed2004

Predictors of virologic failure and resistance in HIV-infected patients treated with nevirapine- or efavirenz-based antiretroviral therapy.

Resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs) increases with the wider use of this class of antiretroviral therapy. The association between adherence and resistance to NNRTI-based regimens is poorly understood. Predictors of virologic failure and resistance according to a baseline evaluation of nonadherence risk factors were determined in a cohort of 71 human immunodeficiency virus (HIV)-infected patients with early virologic response who received an NNRTI-based regimen. During the median follow-up of 29 months, 20 (28%) of 71 patients experienced virologic failure with an NNRTI-based regimen. Virologic failure was associated with repeated drug holidays (> or =48 h of unplanned drug cessation), depression, younger age, and low adherence to therapy during baseline evaluation. Moreover, repeated drug holidays was the only risk factor for developing a major mutation conferring cross-resistance to the NNRTI class (hazard ratio, 22.5; 95% confidence interval, 2.8-180.3; P<.0001). Patients' previous adherence to therapy and drugs genetic barriers, not only the number of pills or doses involved, should be taken into consideration in the decision to simplify highly active antiretroviral therapy.

Adult↗
PubMed2004

Alcoholic povidone-iodine to prevent central venous catheter colonization: A randomized unit-crossover study.

OBJECTIVE: To compare effectiveness in preventing central venous catheter colonization and infection of two protocols of cutaneous antisepsis using povidone-iodine solution in combination with ethanol or water. DESIGN: Randomized trial. SETTING: Medical intensive care department in a university hospital. PATIENTS: Consecutive patients requiring central venous catheter in two similar 11-bed units from January 1, 2001, to January 1, 2002. INTERVENTIONS: Alcoholic povidone-iodine solution protocol was randomly assigned to one of two units when the study began. Every 3 months the alcoholic protocol was switched from one unit to the other. Depending on the unit and the time the patient was admitted, catheters were inserted and cared for with 10% aqueous povidone-iodine solution or 5% povidone-iodine solution 70% ethanol-based combination. MEASUREMENTS AND MAIN RESULTS: Rates of catheter colonization, catheter-related bacteremia, and catheter-related infection were compared in the two protocols; 223 catheters were included in an intent-to-treat analysis. The incidence of catheter colonization was significantly lower in the alcoholic povidone-iodine solution protocol than in the aqueous povidone-iodine solution protocol (relative risk, 0.38; 95% confidence interval, 0.22-0.65, p <.001), and so was the incidence of catheter-related infection (relative risk, 0.34; 95% confidence interval, 0.13-0.91, p <.04). Catheter-related bacteremia were similar in both protocols. After adjusting for other risk factors, time to central venous catheter colonization was significantly longer in the alcoholic solution (adjusted hazards ratio, 0.3; 95% confidence interval, 0.2-0.6, p <.001). Based on a subgroup of 114 patients (57 in each protocol), analysis of 57 pairs of central venous catheters matched for age, duration, and site of insertion found similar results regarding the superiority of alcoholic povidone-iodine solution in preventing central venous catheter colonization and infection. CONCLUSIONS: The use of alcoholic povidone-iodine for skin disinfection reduced the incidence of catheter colonization and related infection compared with aqueous 10% povidone-iodine disinfection in an adult intensive care unit.

Anti-Infective Agents, Local↗
PubMed2002

Cytokine therapy or structured treatment interruptions in HIV infection: which is best?

Continuous highly active antiretroviral therapy (HAART) is the treatment of choice for HIV patients in order to prevent opportunistic infection or AIDS-related morbidity and mortality. However, new HIV treatment strategies are needed to face the emerging problems related to long-term toxicities and failures of HAART. Moreover, total eradication and complete restoration of immune system function cannot be achieved by HAART alone. Therefore, in an attempt to increase the natural immunity of HIV-infected patients, immune-based therapies have been investigated. This review is intended to provide an update on the use of immune-based therapies, in particular structured treatment interruptions and cytokines, such as IL-2 and IFN-alpha, as potential stimulants of the immune system of patients with HIV-infections and to discuss risks and benefits of each alternative. Ongoing and future clinical trials will provide a rationale for their use in clinical practice and will determine how these strategies can be combined to optimise HAART.

Anti-HIV Agents↗