Alomgir Hossain

Mass deworming to improve developmental health and wellbeing of children in low-income and middle-income countries: a systematic review and network meta-analysis

BACKGROUND Soil-transmitted helminthiasis and schistosomiasis, considered among the neglected tropical diseases by WHO, affect more than a third of the worlds population, with varying intensity of infection. We aimed to evaluate the effects of mass deworming for soil-transmitted helminths (with or without deworming for schistosomiasis or co-interventions) on growth, educational achievement, cognition, school attendance, quality of life, and adverse effects in children in endemic helminth areas. METHODS We searched 11 databases up to Jan 14, 2016, websites and trial registers, contacted authors, and reviewed reference lists. We included studies published in any language of children aged 6 months to 16 years, with mass deworming for soil-transmitted helminths or schistosomiasis (alone or in combination with other interventions) for 4 months or longer, that reported the primary outcomes of interest. We included randomised and quasi-randomised trials, controlled before-after studies, interrupted time series, and quasi-experimental studies. We screened in duplicate, then extracted data and appraised risk of bias in duplicate with a pre-tested form. We conducted random-effects meta-analysis and Bayesian network meta-analysis. FINDINGS We included 52 studies of duration 5 years or less with 1 108 541 children, and four long-term studies 8-10 years after mass deworming programmes with more than 160 000 children. Overall risk of bias was moderate. Mass deworming for soil-transmitted helminths compared with controls led to little to no improvement in weight over a period of about 12 months (0·99 kg, 95% credible interval [CrI] -0·09 to 0·28; moderate certainty evidence) or height (0·07 cm, 95% CrI -0·10 to 0·24; moderate certainty evidence), little to no difference in proportion stunted (eight fewer per 1000 children, 95% CrI -48 to 32; high certainty evidence), cognition measured by short-term attention (-0·23 points on a 100 point scale, 95% CI -0·56 to 0·14; high certainty evidence), school attendance (1% higher, 95% CI -1 to 3; high certainty evidence), or mortality (one fewer per 1000 children, 95% CI -3 to 1; high certainty evidence). We found no data on quality of life and little evidence of adverse effects. Mass deworming for schistosomiasis might slightly increase weight (0·41 kg, 95% CrI -0·20 to 0·91) and has little to no effect on height (low certainty evidence) and cognition (moderate certainty evidence). Our analyses do not suggest indirect benefits for untreated children from being exposed to treated children in the community. We are uncertain about effects on long-term economic productivity (hours worked), cognition, literacy, and school enrolment owing to very low certainty evidence. Results were consistent across sensitivity and subgroup analyses by age, worm prevalence, baseline nutritional status, infection status, impact on worms, infection intensity, types of worms (ascaris, hookworm, or trichuris), risk of bias, cluster versus individual trials, compliance, and attrition. INTERPRETATION Mass deworming for soil-transmitted helminths with or without deworming for schistosomiasis had little effect. For schistosomiasis, mass deworming might be effective for weight but is probably ineffective for height, cognition, and attendance. Future research should assess which subset of children do benefit from mass deworming, if any, using individual participant data meta-analysis. FUNDING Canadian Institutes of Health Research and WHO.

Case-control study on occupational risk factors for soft-tissue sarcoma.

Objective: The main objective of this study was to investigate potential association between development of soft-tissue sarcoma (STS) and occupational exposures related to farming and the agricultural industry in Canada. Methodology: A population-based case-control study of STS was conducted among Canadian men stratified by province of residence and age group. Conditional logistic regression was used to fit multivariable statistical models. Results: The following variables were positively associated with the incidence of STS: machinist, chicken farming, pulp and paper industry worker, and apartment complex worker. Mixed farming and exposure to chlorine were negatively associated with STS. Conclusion: The higher risk of developing STS may be associated with longest-held job as a machinist, short-term jobs as chicken farm worker, pulp and paper industry worker, and apartment complex worker.

Canceled coronary computed tomography angiography: Downstream testing and outcomes

BACKGROUND Downstream resource utilization and its impact on outcomes after a canceled CCTA have not been well studied. We sought to understand downstream resource utilization and patient outcomes after canceled CCTA. METHODS AND RESULTS Consecutive patients were prospectively enrolled into an institutional cardiac CT registry. Patients who had the CCTA study canceled because of severe coronary calcification were followed for downstream resource utilization and the composite of all-cause mortality and non-fatal myocardial infarction (MI). 463 patients had their CCTA canceled due to severe coronary calcification and follow-up was available for 453 (97.8%) patients (median follow-up=36.0months). There were a total of 62 events (41 all-cause deaths and 21 non-fatal MI) with an annualized event rate of 4%. Three hundred and twenty patients underwent downstream CAD (ICA or MPI or EST) investigations. Age, NCEP/ATP III risk, beta-blocker use, Agatston and downstream CAD testing were associated with the primary outcome. There were fewer events in those that received downstream CAD testing (30 (9.7%) versus 32 (22.4%)). The annualized event rates for those who did and did not receive downstream CAD testing were 2.8% and 6.2%, respectively. Multivariable analysis confirmed that downstream CAD testing was an independent predictor of event-free survival and that the absence of additional CAD testing was associated with worse outcome (HR: 2.58 (95% CI: 1.54-4.31)). CONCLUSIONS Patients with canceled CCTA due to severe and/or extensive CAC have high rates of death and non-fatal MI. The use of additional CAD testing appears to be associated with improved outcomes.

The Monte Carlo simulation study to conduct comparison between multilevel modeling and standard regression techniques based on cross-sectional complex survey

The multilevel modeling-scaled weights (MM-SW) technique and the standard regression-robust (bootstrap) variance estimation (SR-RV) technique take into account the complexities such as stratification, clustering and unequal probability of the selection of individuals of multistage complex survey data but the ways are different. The performance of these two statistical techniques were examined based on the analysis of real life cross-sectional complex survey data and the Monte Carlo simulation study using cross-sectional complex survey data. The results obtained from the Monte Carlo simulation study indicated that the performance of the MM-SW technique and the SR-RV technique were comparable to analyze the cross-sectional complex survey data although results obtained from the analysis Canadian Heart Health Survey (CHHS) data were inconsistent. Our conclusion based on this study was that both statistical techniques offered similar results when used to analyze the cross-sectional complex survey data; however SR-RV technique might be preferred because it fully accounts for stratification, clustering and unequal probability of selection.

Using coronary calcification to exclude an ischemic etiology for cardiomyopathy: A validation study and systematic review

BACKGROUND Preliminary data suggests the absence of coronary artery calcification (CAC) excludes ischemic etiologies of cardiomyopathy. We prospectively validate and perform a systematic review to determine the utility of an Agatston score=0 to exclude the diagnosis of ischemic cardiomyopathy. METHODS AND RESULTS Patients with newly diagnosed LV dysfunction were prospectively enrolled. Patients underwent CAC imaging and were followed until an etiologic diagnosis of cardiomyopathy was made. Eighty-two patients were enrolled in the study and underwent CAC imaging with 81.7% patients having non-ischemic cardiomyopathy. An Agatston score=0 successfully excluded an ischemic etiology for cardiomyopathy with a specificity of 100% (CI: 74.7-100%) and a positive predictive value of 100% (CI: 85.0%-100%). A systematic literature review was performed and studies were deemed suitable for inclusion if: 1) patients with CHF, cardiomyopathy or LV dysfunction were enrolled, 2) underwent CAC imaging and patients were assessed for an Agatston score=0 or the absence of CAC, and 3) the final etiologic diagnosis (ischemic or non-ischemic) was provided. Eight studies provided sufficient information to calculate operating characteristics for an Agatston score=0 and were combined with our validation cohort for a total of 754 patients. An Agatston score=0 excluded ischemic cardiomyopathy with specificity and positive predictive values of 98.4% (CI: 95.6-99.5%), and 98.3% (CI: 95.5-99.5%), respectively. CONCLUSIONS In patients with cardiomyopathy of unknown etiology, an Agatston score=0 appears to rule out an ischemic etiology. A screening CAC may be a simple and cost-effective method of triaging patients, identifying those who do and do not need additional CAD investigations.