Estimating the number of probable new SARS-CoV-2 infections among tested subjects from the number of confirmed cases.

OBJECTIVES: In most African countries, confirmed COVID-19 case counts underestimate the number of new SARS-CoV-2 infection cases. We propose a multiplying factor to approximate the number of biologically probable new infections from the number of confirmed cases. METHODS: Each of the first thousand suspect (or alert) cases recorded in South Kivu (DRC) between 29 March and 29 November 2020 underwent a RT-PCR test and an IgM and IgG serology. A latent class model and a Bayesian inference method were used to estimate (i) the incidence proportion of SARS-CoV-2 infection using RT-PCR and IgM test results, (ii) the prevalence using RT-PCR, IgM and IgG test results; and, (iii) the multiplying factor (ratio of the incidence proportion on the proportion of confirmed -RT-PCR+- cases). RESULTS: Among 933 alert cases with complete data, 218 (23%) were RT-PCR+; 434 (47%) IgM+; 464 (~ 50%) RT-PCR+, IgM+, or both; and 647 (69%) either IgG + or IgM+. The incidence proportion of SARS-CoV-2 infection was estimated at 58% (95% credibility interval: 51.8-64), its prevalence at 72.83% (65.68-77.89), and the multiplying factor at 2.42 (1.95-3.01). CONCLUSIONS: In monitoring the pandemic dynamics, the number of biologically probable cases is also useful. The multiplying factor helps approximating it.

[Benign prostatic hyperplasia surgery and patient's information: What do patients understand and remember?] / Chirurgie de l'hypertrophie bénigne de prostate et information des patients : qu'est ce que les patients comprennent et retiennent ?

INTRODUCTION: Preoperative information is a key to adherence to treatment for the patients, but may be misunderstood because of its density and complexity. The aim of this study was to assess comprehension and satisfaction of patients about preoperative information of benign prostatic hyperplasia (BPH) surgery. Factors influencing patient understanding were also studied. PATIENTS AND METHODS: It was a monocentric study on questionnaires including every patients planned for BPH surgery, whatever the surgical technique. A survey was sent at patient's home after the preoperative consultation. RESULTS: One hundred and six of 210 patients (50,5 %) returned the questionnaire. 38,68 % (n=41) found the quality of information excellent (9 or 10 out of 10), and 45,28 % (n=48) found the quality of information good (7 or 8 out of 10). The main recalled complications were retrograde ejaculation (39.6 %, n=42/106), and bleeding (29,2 %, n=31/106). 57.6 % of patients (n=61) remembered receiving the written information sheet of the French Association of Urology. 5.7 % (n=6) hesitated having the procedure. Only patient's age was significantly associated with difference of comprehension (p<0.005). CONCLUSION: Information given before a BPH surgery seems satisfactory although it was poorly understood, notably about complications. Providing complete oral information, insisting on complications, and giving the written information sheet are essential for a good doctor-patient relationship and a forensic serenity. LEVEL OF EVIDENCE: 3.

Impact of stopping sending colorectal cancer screening test kits by regular mail.

OBJECTIVE: From 2009 to 2013, the French colorectal cancer screening program (CRCSP) provided for a medical phase and a phase of systematic mailing of the test kit (SMTK) to people who could not participate in the medical phase. After 2013, the SMTK was abandoned in most districts. This study aims to analyze the impact of this termination. STUDY DESIGN: This was a descriptive and cohort study. METHODS: The study concerned a cohort of 143,989 people (aged 50-74 years) living in Seine-Saint-Denis (France), invited to participate in the 2013 campaign (with SMTK) and in the 2015 campaign (without SMTK). The impact of SMTK termination was analyzed in terms of the difference between the participation rates and between the delay (expected vs observed) in performing the screening test in 2015. These differences were described based on previous solicitation in the CRCSP. Expected rates and expected delay were estimated in a Monte Carlo simulation. RESULTS: The participation rate observed (20.0%) was higher than expected (16.1% [15.9-16.3]). People who have never had a SMTK between 2007 and 2013 (80.0% [79.3-80.7] vs 69.6%) and those who participated in all campaigns before 2015 (97.0% [96.7-97.3] vs 82.6%) had an observed rate lower than expected. The delay observed (4.2 months) was longer than expected (2.5 months). CONCLUSION: The sudden termination certainly contributed to the extension of the delay. However, it did not have a major impact on the participation rate, partly due to information campaigns on the new screening test. In this cohort, the low participation would be explained better by the behavior in the previous campaigns than by the lack of SMTK.

Improving survival in end-stage renal disease: A case study.

Background: With the increase of life expectancy, *On behalf of the REIN registry. end-stage renal disease (ESRD) is affecting a growing number of people. Simultaneously, renal replacement therapies (RRTs) have considerably improved patient survival. We investigated the way current RRT practices would affect patients' survival. Methods: We used a multi-state model to represent the transitions between RRTs and the transition to death. The concept of "crude probability of death" combined with this model allowed estimating the proportions of ESRD-related and ESRD-unrelated deaths. Estimating the ESRD-related death rate requires comparing the mortality rate between ESRD patients and the general population. Predicting patients' courses through RRTs and Death states could be obtained by solving a system of Kolmogorov differential equations. The impact of practice on patient survival was quantified using the restricted mean survival time (RMST) which was compared with that of healthy subjects with same characteristics. Results: The crude probability of ESRD-unrelated death was nearly zero in the youngest patients (18-45 years) but was a sizeable part of deaths in the oldest (≥70 years). Moreover, in the oldest patients, the proportion of expected death was higher in patient without vs. with diabetes because the former live older. In men aged 75 years at first RRT, the predicted RMSTs in patients with and without diabetes were, respectively, 61% and 69% those of comparable healthy men. Conclusion: Using the concept of "crude probability of death" with multi-state models is feasible and useful to assess the relative benefits of various treatments in ESRD and help patient long-term management.

Construction and feasibility study of the SOFMER Activity Score (SAS), a new assessment of physical and cognitive activity.

OBJECTIVES: For hospitalizations in rehabilitation centers (RCs) in France, the quantification of healthcare givers' activity is based on the dependency of the patients, defined as a total or partial inability to perform activities required for daily living without help. The tools currently used to quantify dependency are not sufficiently precise. Here we describe the construction of a new tool, the SOFMER Activity Score (SAS scoring), which allows for a good description of the level of activity of patients hospitalized in RCs, and a feasibility study of the tool. METHODS: After a study group proposed the first version of the SAS, the validity of its content was studied by the Delphi consensus method: 26 physicians or healthcare professionals known for their expertise in PMR responded to the first round. The feasibility study was prospective and involved multi-site professionals. Data related to the SAS determined by a multidisciplinary team were collected and compared to the Activité de la Vie Quotidienne (AVQ) scale, which is administered to all patients and included in medical and administrative data. RESULTS: We included 81 patients in the feasibility study. The mean (SD) time to obtain the SAS was 4.5 (3.3) min. For 97.5% of scorings, the participating professionals judged that the SAS was compatible or fairly compatible with clinical practice. The internal structure of the SAS scale seemed better than that of the AVQ scale, for which the present study confirmed a floor effect for all items. CONCLUSIONS: The SAS allows for measuring the level of physical and cognitive activity of a patient hospitalized in an RC. If validation studies for the SAS, exploring its reliability, construct validity or criterion validity, confirm the tool's good metrological qualities, the SAS will allow for a good quantification of the burden of care.

Evolution of the incidence of hepatitis B virus infection and immunization rates in a large French cohort born between 1960 and 1994.

In France, several successive changes in anti-hepatitis B virus (HBV) vaccination policies occurred since 1982. We estimated the incidence and prevalence of HBV infection according to years of birth 1960 to 1994 in a large sentinel cohort to evaluate the epidemiology of HBV during vaccination policy changes. A retrospective cohort study included data from all HIV, HBV and hepatitis C virus (HCV) screening facilities in Grand Lyon. From 2005 to 2010, all 57113 individuals with complete HBV serologic status were enrolled. Survival analyses modeled separately various ages in each birth cohort. The proportion of immunized individuals increased in birth cohorts 1978 to 1984 (up to 58.3% (95% confidence interval (CI), 43.3-68.2 at age 15). In post-1985 birth cohorts, this proportion decreased to 19.5% (95% CI, 15.5-24) in birth cohort 1987 at age 15. Probability of past or current HBV infection increased constantly in birth cohorts 1960 to 1967, up to 12% (95% CI, 10.4-14) at age 30, then decreased gradually in birth cohorts 1968 to 1991, down to 0.9% (95% CI, 0.7-1.2) at age 17.5. In post-1991 cohorts, the probability of HBV infection increased again, up to 2.5% (95% CI, 1.7-3.6) at age 17.5. HBV incidence fluctuated between 5 and 8 per 1000 person-years in pre-1986 birth cohorts, decreased to 2.1 (95% CI, 1.5-2.7) in birth cohorts 1986 to 1991 but rebounded to 5 (95% CI, 3.5-7.1) in post-1991 birth cohorts. HBV incidence was remarkably high in young adults with noticeable variations concomitantly to vaccination policy changes. A dramatic decline in immunization rate was temporally associated with a sharp rebound of infection after withdrawal of systematic adolescent vaccination in 1998.

Influence of observable and unobservable exposure on the patient's risk of acquiring influenza-like illness at hospital.

During outbreaks of hospital-acquired influenza-like illness (HA-ILI) healthcare workers (HCWs), patients, and visitors are each a source of infection for the other. Quantifying the effects of these various exposures will help improve prevention and control of HA-ILI outbreaks. We estimated the attributability of HA-ILI to: (1) exposure to recorded or unrecorded sources; (2) exposure to contagious patient or contagious HCW; (3) exposure during observable or unobservable contagious period of the recorded sources; and, (4) the moment of exposure. Among recorded sources, 59% [95% credible interval (CrI) 34-83] of HA-ILI of patients was associated with exposure to contagious patients and 41% (95% CrI 17-66) with exposure to contagious HCWs. Exposure during the unobservable contagiousness period of source patients accounted for 49% (95% CrI 19-75) of HA-ILI, while exposure during the unobservable contagiousness period of source HCWs accounted for 82% (95% CrI 51-99) of HA-ILI. About 80% of HA-ILIs were associated with exposure 1 day earlier. Secondary cases of HA-ILI might appear as soon as the day after the detection of a primary case highlighting the explosive nature of HA-ILI spread. Unobservable transmission was the main cause of HA-ILI transmission suggesting that symptom-based control measures alone might not prevent hospital outbreaks. The results support the rapid implementation of interventions to control influenza transmission.

Influenza vaccine effectiveness among healthcare workers in comparison to hospitalized patients: A 2004-2009 case-test, negative-control, prospective study.

The objective of this study was to calculate Vaccine Effectiveness (VE) in healthcare workers (HCW) and to compare VE between patients and HCW. A case-control investigation based on the prospective study was conducted between 2004 and 2009 in a teaching hospital. All HCW with influenza-like illness (ILI) from participating units (n = 24) were included, and vaccination status was characterized by interview. A total of 150 HCW presented ILI; 130 (87%) were female, 27 (18%) were positive for influenza, and 42 (28%) were vaccinated. Adjusted VE was 89% (95% CI 39 to 98). Among patients, adjusted VE was 42% (95% CI -39 to 76). The difference of VE (VEhcw - VEpat) was 46.15% (95% CI 2.41 to 144). The VE ratio (VEhcw / VEpat) was 2.09 (95% CI -1.60 to 134.17). Influenza VE differed between HCW and patients when the flu season was taken into account. This finding confirms the major impact of host determinants on influenza VE.

Estimating the parameters of multi-state models with time-dependent covariates through likelihood decomposition.

BACKGROUND: Multi-state models become complex when the number of states is large, when back and forth transitions between states are allowed, and when time-dependent covariates are inevitable. However, these conditions are sometimes necessary in the context of medical issues. For instance, they were needed for modelling the future treatments of patients with end-stage renal disease according to age and to various treatments. METHODS: The available modelling tools do not allow an easy handling of all issues; we designed thus a specific multi-state model that takes into account the complexity of the research question. Parameter estimation relied on decomposition of the likelihood and separate maximisations of the resulting likelihoods. This was possible because there were no interactions between patient treatment courses and because all exact times of transition from any state to another were known. Poisson likelihoods were calculated using the time spent at risk in each state and the observed transitions between each state and all others. The likelihoods were calculated on short time intervals during which age was considered as constant. RESULTS: The method was not limited by the number of parameters to estimate; it could be applied to a multi-state model with 10 renal replacement therapies. Supposing the parameters of the model constant over each of seven time intervals, this method was able to estimate one hundred age-dependent transitions. CONCLUSIONS: The method is easy to adapt to any disease with numerous states or grades as long as the disease does not imply interactions between patient courses.

Random serum progesterone threshold to confirm ovulation.

BACKGROUND: Serum progesterone (P) rises after ovulation in the luteinisation process. OBJECTIVE: To identify an accurate progesterone threshold to confirm ovulation in the assessment of a woman's fertility. METHODS: In a secondary analysis of an observational European multicentre study, this study included 107 women over 326 menstrual cycles and tracked daily first morning urine (FMU), changes in observed cervical mucus discharge, serum progesterone, and ultrasonography to identify the day of ovulation. A serum progesterone level was available for 102 women over a total 260 cycles with one or two P levels per cycle. RESULTS: It was found that a single serum P⩾5ng/ml is highly specific with a specificity of 98.4 (95% CI 96.0-99.5), with a sensitivity of 89.6 (95% CI 85.2-92.9). CONCLUSION: A random serum progesterone level ⩾5ng/ml confirms ovulation. This may be of use for clinicians wanting to confirm that ovulation has occurred.

Development and validation of a motor function classification in patients with neuromuscular disease: the NM-score.

OBJECTIVE: To develop a classification for neuromuscular disease patients in each of the three motor function domains (D1: standing and transfers; D2: axial and proximal function; D3: distal function). MATERIALS AND METHODS: A draft classification was developed by a study group and then improved by qualitative validation studies (according to the Delphi method) and quantitative validation studies (content validity, criterion validity and inter-rater reliability). A total of 448 patients with genetic neuromuscular diseases participated in the studies. RESULTS: On average, it took 6.3minutes to rate a patient. The inter-rater agreement was good when the classification was based on patient observation or an interview with the patient (Cohen's kappa=0.770, 0.690 and 0.642 for NM-Score D1, D2 and D3 domains, respectively). Stronger correlations (according to Spearman's coefficient) with the respective "gold standard" classifications were found for NM-Score D1 (0.86 vs. the Vignos Scale and -0.88 vs. the Motor Function Measure [MFM]-D1) and NM-Score D2 (-0.7 vs. the Brooke Scale and 0.64 vs. MFM D2) than for NM-Score D3 (0.49 vs. the Brooke scale and -0.49 vs. MFM D3). DISCUSSION/CONCLUSIONS: The NM-Score is a reliable, reproducible outcome measure with value in clinical practice and in clinical research for the description of patients and the constitution of uniform patient groups (in terms of motor function).

[Preoperative endorectal MRI in prostate cancer: a monocentric retrospective cohort]. / Place de l'IRM prostatique avant prostatectomie radicale. Cohorte monocentrique rétrospective.

INTRODUCTION: The aim of the study was to assess the added value of a prostatic MRI performed in a non-expert center before radical prostatectomy for prostate cancer. PATIENTS AND METHODS: All patients considered for a radical prostatectomy for a clinically localised prostate cancer in our institution between June 2006 and April 2011 were analysed. They underwent a systematic endorectal 1.5 T MRI [eMRI] (T2 and diffusion-weighted imaging). The procedure was performed at least 8 weeks after transrectal ultrasound guided prostate biopsies. They were analyzed by a single experimented genitourinary radiologist. The preoperative characteristics and biopsy data were collected, as the eMRI interpretation using a systematic scale. Correlation between eMRI and final histopathology has been analyzed (standardized pathological report using the Stanford procedure). We considered the following points: extracapsular extension, seminal vesicle invasion and cancer localisation. Cancer localization was analyzed both by halves (left/right) and on sextant-basis (base, middle, apex, left and right respectively). For each data, sensitivity, specificity, positive (PPV) and negative predictive value (NPV) were calculated. Finally, we compared the results with those from the Partin's table and the Kattan's nomogram for T stage. RESULTS: Two hundred and fifteen patients underwent a radical prostatectomy, having a mean age of 63 ± 6 years, a mean PSA: 7.8 ± 3.8 ng/mL. One hundred and fifty-nine patients had organ confined disease. Fifty-six had pT3 disease (50 pT3a and 6 pT3b). Sensibilities and specificities were the following: for extracapsular extension 26% and 96%; for seminal vesicle invasion 17% and 98%; for cancer localisation 64% and 74%; for prediction of left or right side 81% and 48%. DISCUSSION: MRI showed equal performances compared to the Partin's table and the Kattan's nomogram for T stage. It showed lower performance compared to biopsy results for cancer localization (sensitivity 88%, specificity 70%). Literature provides wide ranges of results for eMRI. The results of this study were at the low limit of these ranges but reflect everyday practice. When performed, as it was in our study, eMRI did not seem to be accurate for staging. It had at best a very limited added value compared to the existing tools.

Use of urinary pregnanediol 3-glucuronide to confirm ovulation.

OBJECTIVE: Urinary hormonal markers may assist in increasing the efficacy of Fertility Awareness Based Methods (FABM). This study uses urinary pregnanediol-3a-glucuronide (PDG) testing to more accurately identify the infertile phase of the menstrual cycle in the setting of FABM. METHODS: Secondary analysis of an observational and simulation study, multicentre, European study. The study includes 107 women and tracks daily first morning urine (FMU), observed the changes in cervical mucus discharge, and ultrasonography to identify the day of ovulation over 326 menstrual cycles. The following three scenarios were tested: (A) use of the daily pregnandiol-3a-glucuronide (PDG) test alone; (B) use of the PDG test after the first positive urine luteinizing hormone (LH) kit result; (C) use of the PDG test after the disappearance of fertile type mucus. Two models were used: (1) one day of PDG positivity; or (2) waiting for three days of PDG positivity before declaring infertility. RESULTS: After the first positivity of a LH test or the end of fertile mucus, three consecutive days of PDG testing over a threshold of 5µg/mL resulted in a 100% specificity for ovulation confirmation. They were respectively associated an identification of an average of 6.1 and 7.6 recognized infertile days. CONCLUSIONS: The results demonstrate a clinical scenario with 100% specificity for ovulation confirmation and provide the theoretical background for a future development of a competitive lateral flow assay for the detection of PDG in the urine.

Factors associated with hospital mortality in community-acquired legionellosis in France.

The aims of this study were to describe the clinical, biological and radiological features of community-acquired (CA) Legionnaires' disease (LD) and identify the predictors of mortality in hospitalised patients. Demographic data, risk factors, clinical and biological features, medical management, complications, and outcome from 540 hospitalised patients with confirmed CA LD were prospectively recorded. 8.1% of patients (44 out of 540) died. The predictors of survival after Kaplan-Meier analysis were male sex (p = 0.01), age <60 yrs (p = 0.02), general symptoms (p = 0.006), intensive care unit (ICU) stay (p<0.001), and class II-III Pneumonia Severity Index score (p = 0.004). Six predictors of death were identified by multivariate analysis: age (per 10-yr increment) (relative hazard (RH) 1.50, 95% CI 1.21-1.87), female sex (RH 2.00, 95% CI 1.08-3.69), ICU admission (RH 3.31, 95% CI 1.67-6.56), renal failure (RH 2.73, 95% CI 1.42-5.27), corticosteroid therapy (RH 2.54, 95% CI 1.04-6.20) and C-reactive protein (CRP) >500 mg · L(-1) (RH 2.14, 95% CI 1.02-4.48). Appropriate antibiotic therapy was prescribed for 70.8% (292 out of 412) of patients after admission and for 99.8% (537 out of 538) of patients after diagnosis confirmation. In conclusion, female sex, age, ICU stay, renal failure, corticosteroid treatment and increased level of CRP are significant risk factors for mortality in CA LD.

Relative Change in NT-proBNP Level: An Important Risk Predictor of Cardiovascular Congestion in Haemodialysis Patients.

BACKGROUND: Cross-sectional studies have shown that B-type natriuretic peptide (BNP) and its N-terminal fragment (NT-proBNP) are predictive of cardiovascular death in haemodialysis (HD) patients. In the present study, we tested the hypothesis that monitoring NT-proBNP measurements adds further prognostic information, i.e. predicts congestive heart failure (CHF) events. METHODS: In a prospective cohort of 236 HD patients, NT-proBNP levels were measured monthly during 18 months. Patients were divided according to the occurrence of CHF events. In a nested case-control study, we assessed the evolution of NT-proBNP levels. RESULTS: On average, the 236 HD patients were followed up for 12.5 months, a period during which 44 patients developed a CHF event (half requiring hospitalisation). At baseline, patients who developed a CHF event had significantly more dilated cardiomyopathy and/or altered left ventricular ejection fraction and higher NT-proBNP levels compared with patients who did not develop a CHF event. During follow-up, we observed a significant increase in NT-proBNP levels preceding the CHF event. At a 20% relative increase of NT-proBNP, the sensitivity of NT-proBNP as a predictor of CHF events was 0.57 and the specificity 0.77. CONCLUSION: The relative change in NT-proBNP levels is a significant risk predictor of a CHF event.

Puberty and pubertal growth dynamics in children with idiopathic short stature.

OBJECTIVE: As the prognosis for final height is unfavorable for children with idiopathic short stature (ISS), we studied the pubertal growth dynamics in these children, which is a determinant factor in final height. SUBJECTS/METHODS: In a retrospective cohort study, we analyzed the pubertal period, age of puberty and peripubertal growth in 50 children with ISS. RESULTS: The onset of puberty occurred later. Growth rate tended to become increasingly subnormal in the prepubertal period and height was -2.45 SD at puberty onset. Growth reaccelerated at this point, which tended to correct the deviation from the mean height, but it was insufficient to obtain a normal final height. CONCLUSIONS: The dynamics of growth in children with ISS showed a distinct pattern in the prepubertal and pubertal periods and puberty is significantly delayed in this population. These patterns could explain the unfavorable prognosis for children with ISS.

[Diversity of incidence trend patterns: implications for carcinogenesis?]. / Diversité des modèles d'évolution des incidences: implication en cancérogenèse?

OBJECTIVE: Cancers of the ENT, oesophagus and lungs are caused mainly by alcohol and/or tobacco consumption but have potentially heterogeneous latencies and dose-incidence relationships. The incidence of cancers having the same risk factors may vary in a similar way over time and space. The aim of the study was to identify groups of cancers with similar spatio-temporal incidence trends. METHODS: Fifty thousand nine hundred and eighty cases of ten cancer types were collected between 1982 and 2002 in six French departments. The incidence levels and trends were assessed using an age-cohort random-effect model that took into account heterogeneity of incidence levels and trends between departments. RESULTS: Three groups of cancer sites/types with similar spatio-temporal incidence trends were identified: (1) oral cavity, oropharynx, hypopharynx, larynx, oesophagus, and lung squamous cell carcinomas in which the incidence decreased similarly in time and space; (2) other types of lung cancer and lung adenocarcinomas whose incidence increased similarly; and (3) lung large- and small-cell carcinomas whose incidence trends were heterogeneous. CONCLUSION: Using the tools of descriptive epidemiology different cancer groups with different temporal and spatial incidence trends were identified. This diversity suggests different latencies and different sensitivities of those groups to the main risk factors, alcohol and tobacco.

Effects of branched amino acids supplementation in malnourished elderly with catabolic status.

BACKGROUND: Among various nutrients branched amino acids (BCAAS) have been shown to be the most responsible for the stimulation of protein synthesis in various situations including catabolic states. OBJECTIVES: We evaluated the effect of a small amount of proteins enriched with BCAAs (0.4 g/kg/day and 0.2 g/kg/day BCAAs) on body weight and composition; nitrogen balance, energy intake and inflammation after 2 weeks of supplementation in acute elderly with catabolic status. DESIGN: Two weeks randomized controlled trial. SETTING: Geriatric department of teaching hospital. SUBJECTS: Thirty patients with malnutrition and inflammatory process (MNA < 24, albumin < 30 g/l and CRP > or = 20 mg/l) who agreed to participate in the study were consecutively included. METHODS: Body composition was determined by labelled water dilution method; resting energy expenditure (REE) was determined by indirect calorimetry; energy intake was calculated for a 3 days period at D1 and D12. Nutritional and inflammatory proteins and cytokines (IL-6 and TNF) were measured at day 1 and 14. RESULTS: No difference was observed at day 14 between supplemented (S) and control (C) group for weight (S: 58.0 +/- 11.8 kg and C: 60.0 +/- 15.9 kg); fat free mass (S: 40.7 +/- 8.3 kg and C: 40 +/- 8.2 kg); nitrogen balance (S: 1.34 +/- 2.21 g/day and C: 0.59 +/- 4.47 g/day); and energy intake (S: 20 +/- 3.6 kcal/day and C: 20.5 +/- 8.6 kcal/day). Energy intake was at similar level than REE and clearly less than energy requirement in C and S. A significant decrease was observed for orosomucoid and Prognostic Inflammatory and Nutritional Index (PINI) in S. CONCLUSION: Our results do not confirm improvement of nutritional status with enriched BCAAs supplementation as suggested in the literature. Persistence of inflammatory condition may be an explanation despite an improvement of inflammatory status was observed in the supplemented group. Those results show clearly that energy requirements are not covered in acute hospitalized elderly people. The fact that not only energy intake but also REE are decreased brings a new insight on catabolic situations.

Detecting related cases of bloodstream infections using time-interval distribution modelling.

An algorithm was designed to highlight related bloodstream infections using data from a nosocomial infection surveillance system to help local public health authorities direct specific measures towards clusters of cases. The approach was based on a two-step procedure. The first was a test to identify pathogens with an abnormal number of close cases. The second modelled, for the identified pathogens, the distribution of time intervals between successive cases as a mixture of two theoretical distributions in order to determine a threshold below which a specific investigation is required. The algorithm was applied to bloodstream infection surveillance data collected during a 10-year period (1996-2005) in an 878-bed teaching hospital (24 wards) in Lyon, France. The first step identified seven pathogens among the 18 being studied. The modelling succeeded in setting time thresholds to spot clusters of cases requiring further investigation with defined sensitivity and specificity. Setting the sensitivity level at 95%, the threshold values ranged from 24 days (Acinetobacter baumannii) to 294 days (Enterobacter cloacae); the specificity was higher than 70% (up to 97.5% for A. baumannii) except for E. cloacae (52.1%). Setting the specificity level at 95% resulted in a decrease in sensitivity except for A. baumannii (it reached nearly 100%); it fell below 50% for three pathogens: around 40% for Streptococcus pneumoniae and Enterococcus faecalis and 25% for Enterobacter cloacae. The threshold values then ranged from 8 days (S. pneumoniae) to 67 days (Streptococcus pyogenes). The approach proved promising though further refinements are needed before routine use.

Adherence to antiretroviral therapy, virological response, and time to resistance in the Dakar cohort.

In 1998, with the launch of the Senegalese Initiative for Antiretroviral Access (ISAARV), Senegal became one of the first African countries to propose an antiretroviral access program. Our objective in this paper is to study the time to any first drug resistance, as well as predictors of the time to resistance. We propose a joint model to study the effect of adherence to the HAART therapy, and virological response on the time to resistance mutations. A logistic mixed model is used to model the time-dependent adherence process; and a Markov model is used to study the virological response. Given the presence of missing data in the adherence process and in the virological response, the latent adherence and virological states are then included in the linear predictor of the time to resistance model. The proposed time to resistance model takes into account interval-censored data as well as null hazard periods, during which the viral replication is very low. A Bayesian approach is used for accommodating with missing data and for prediction. We also propose model checking tools to study model adequacy.