The utility and predictive value of combinations of low penetrance genes for screening and risk prediction of colorectal cancer

Despite the fact that colorectal cancer (CRC) is a highly treatable form of cancer if detected early, a very low proportion of the eligible population undergoes screening for this form of cancer. Integrating a genomic screening profile as a component of existing screening programs for CRC could potentially improve the effectiveness of population screening by allowing the assignment of individuals to different types and intensities of screening and also by potentially increasing the uptake of existing screening programs. We evaluated the utility and predictive value of genomic profiling as applied to CRC, and as a potential component of a population-based cancer screening program. We generated simulated data representing a typical North American population including a variety of genetic profiles, with a range of relative risks and prevalences for individual risk genes. We then used these data to estimate parameters characterizing the predictive value of a logistic regression model built on genetic markers for CRC. Meta-analyses of genetic associations with CRC were used in building science to inform the simulation work, and to select genetic variants to include in logistic regression model-building using data from the ARCTIC study in Ontario, which included 1,200 CRC cases and a similar number of cancer-free population-based controls. Our simulations demonstrate that for reasonable assumptions involving modest relative risks for individual genetic variants, that substantial predictive power can be achieved when risk variants are common (e.g., prevalence > 20%) and data for enough risk variants are available (e.g., ~140–160). Pilot work in population data shows modest, but statistically significant predictive utility for a small collection of risk variants, smaller in effect than age and gender alone in predicting an individual’s CRC risk. Further genotyping and many more samples will be required, and indeed the discovery of many more risk loci associated with CRC before the question of the potential utility of germline genomic profiling can be definitively answered

Radiofrequency catheter ablation of supraventricular tachycardia in children and adolescents: Feasibility and cost-effectiveness in a low-income country

The objective of this study is to provide results and costs of catheter ablation in children and adolescents in a low-income country. Reports from first-world countries have demonstrated the cost-effectiveness of radiofrequency catheter ablation (RFCA) compared to medical treatment of supraventricular tachycardia (SVT). The study included 28 patients younger than 18 years of age with SVT in a pediatric cardiology unit in Guatemala. All patients underwent RFCA. Clinical outcome and cost-effectiveness of RFCA compared to continued medical treatment were the end points. Twenty-four patients had successful ablation (85.7%). Mean age at RFCA was 11.42 \ub1 3.49 years. Three patients underwent a second ablation, increasing the success rate to 96.4%. One remaining patient is awaiting a second procedure. At a mean follow-up of 13.69 \ub1 7.16 months, all 27 patients who had a successful ablation remained in sinus rhythm. Mean cost per procedure was 4.9 times higher than that of medical treatment. However, the estimated cost of catheter ablation equal that of medical therapy after 5.1 years and is 3.4 times less after 20 years. Radiofrequency catheter ablation of SVT in children and adolescents is safe and cost-effective compared to medical therapy. Resources must be judiciously allocated, especially in low-income countries, to treat the largest number of pediatric patients. \ua9 Springer Science+Business Media, Inc. 2006

Age, comorbidities, and AIDS predict a frailty phenotype in men who have sex with men.

BackgroundAdults aging with HIV infection are at risk for age-related comorbidities and syndromes, such as frailty. The objective of this study was to evaluate the expression and predictors of the frailty phenotype (FP) among HIV-infected (HIV+) and HIV-uninfected (HIV-) men who have sex with men.MethodsA prospective, observational cohort study was nested in the Multicenter AIDS Cohort Study from October 2007-September 2011. FP conversion was defined as the onset of FP over two consecutive study visits. Adjusted odds ratios and 95% confidence intervals ([,]) for FP conversion were estimated using logistic regression models with generalized estimating equations.ResultsOf 10,571 completed study visits from 1,946 men who have sex with men, 12% and 9% were FP+ among HIV+ and HIV- men, respectively (p = .002). The proportion of FP+ visits increased with age regardless of HIV status, but was significantly greater in HIV+ compared to HIV- men aged 50-64 years. Of the 10,276 consecutive visit pairs contributed by participants, 5% (537) were classified as FP conversion, and 45% of the men with FP conversion had only one FP+ study visit. FP conversion was significantly associated with a history of AIDS (adjusted odds ratios = 2.26 [1.50, 3.39], but not with HIV+ alone (adjusted odds ratios = 1.26 [0.98, 1.64]). Among men who had one or more FP+ visits, 34% of HIV+ and 38% of HIV- men had less than two comorbidities.ConclusionsThese findings suggest that expression of the FP can be measured in men who have sex with men with and without HIV infection and reflects multisystem dysfunction in this population; further investigations are needed to better understand clinical utility

A case of mistaken identity

What went wrong between the UK media and a report on 'multi-ethnic' Britain

Multiple courses of antenatal corticosteroids for preterm birth (MACS): a randomised controlled trial

BACKGROUND: One course of antenatal corticosteroids reduces the risk of respiratory distress syndrome and neonatal death. Weekly doses given to women who remain undelivered after a single course may have benefits (less respiratory morbidity) or cause harm (reduced growth in utero). We aimed to find out whether multiple courses of antenatal corticosteroids would reduce neonatal morbidity and mortality without adversely affecting fetal growth. METHODS: 1858 women at 25-32 weeks' gestation who remained undelivered 14-21 days after an initial course of antenatal corticosteroids and continued to be at high risk of preterm birth were randomly assigned to multiple courses of antenatal corticosteroids (n=937) or placebo (n=921), every 14 days until week 33 or delivery, whichever came first. The primary outcome was a composite of perinatal or neonatal mortality, severe respiratory distress syndrome, intraventricular haemorrhage (grade III or IV), periventricular leucomalacia, bronchopulmonary dysplasia, or necrotising enterocolitis. Analysis was by intention to treat. All patients and caregivers were unaware of the treatment given. This trial is registered as number ISRCTN2654148. FINDINGS: Infants exposed to multiple courses of antenatal corticosteroids had similar morbidity and mortality to those exposed to placebo (150 [12.9%] vs 143 [12.5%]). Those receiving multiple doses of corticosteroids also weighed less at birth than those exposed to placebo (2216 g vs 2330 g, p=0.0026), were shorter (44.5 cm vs 45.4 cm, p<0.001), and had a smaller head circumference (31.1 cm vs 31.7 cm, p<0.001). INTERPRETATION: Multiple courses of antenatal corticosteroids, every 14 days, do not improve preterm-birth outcomes, and are associated with a decreased weight, length, and head circumference at birth. Therefore, this treatment schedule is not recommended. FUNDING: Canadian Institutes of Health Research