Search

The benefits of large-scale genetic studies for healthcare of the populations studied are well documented, but these genetic studies have traditionally ignored people from some parts of the world, such as South Asia. Here we describe whole genome sequence (WGS) data from 4806 individuals recruited from the healthcare delivery systems of Pakistan, India and Bangladesh, combined with WGS from 927 individuals from isolated South Asian populations. We characterize population structure in South Asia and describe a genotyping array (SARGAM) and imputation reference panel that are optimized for South Asian genomes. We find evidence for high rates of reproductive isolation, endogamy and consanguinity that vary across the subcontinent and that lead to levels of rare homozygotes that reach 100 times that seen in outbred populations. Founder effects increase the power to associate functional variants with disease processes and make South Asia a uniquely powerful place for population-scale genetic studies.

Currently, no treatments available for Parkinson's disease (PD) can slow PD progression. At the early stage of the disease, only a subset of individuals with PD progress quickly, while the majority have a slowly progressive form of the disease. In developing treatments that aim to slow PD progression, clinical trials aim to include individuals who are likely to progress faster, such that a treatment effect, if one exists, can be identified easier and earlier. The aim of the present study was to identify baseline predictors of clinical progression in early PD. We analyzed 12-month data acquired from the PASADENA trial Part 1 (NCT03100149, n = 76 participants who were allocated to the placebo arm and did not start symptomatic therapy) and the Parkinson's Progression Markers Initiative (PPMI) study (n = 139 demographically and clinically matched participants). By using ridge regression models including clinical characteristics, imaging, and non-imaging biomarkers, we found that Hoehn and Yahr stage and dopamine transporter single-photon emission computed tomography specific binding ratios (Dat-SPECT SBR) in putamen ipsilateral to the side of motor symptom onset predicted PD progression at the early stage of the disease. Further studies are needed to confirm the validity of these predictors to identify with high accuracy individuals with early PD with a faster progression phenotype.

AbstractPopulation-scale genetic studies can identify drug targets and allow disease risk to be predicted with resulting benefit for management of individual health risks and system-wide allocation of health care delivery resources. Although population-scale projects are underway in many parts of the world, genetic variation between population groups means that additional projects are warranted. South Asia has a population whose genetics is the least characterized of any of the world’s major populations. Here we describe GenomeAsia studies that characterize population structure in South Asia and that create tools for economical and accurate genotyping at population-scale. Prior work on population structure characterized isolated population groups, the relevance of which to large-scale studies of disease genetics is unclear. For our studies we used whole genome sequence information from 4,807 individuals recruited in the health care delivery systems of Pakistan, India and Bangladesh to ensure relevance to population-scale studies of disease genetics. We combined this with WGS data from 927 individuals from isolated South Asian population groups, and developed a custom SNP array (called SARGAM) that is optimized for future human genetic studies in South Asia. We find evidence for high rates of reproductive isolation, endogamy and consanguinity that vary across the subcontinent and that lead to levels of homozygosity that approach 100 times that seen in outbred populations. We describe founder effects that increase the power to associate functional variants with disease processes and that make South Asia a uniquely powerful place for population-scale genetic studies.

BackgroundRecognizing the factors associated with falling in Parkinson's disease (PD) would improve identification of at-risk individuals.ObjectiveTo examine frequency of falling and baseline characteristics associated with falling in PD using the National Institute of Neurological Disorders and Stroke (NINDS) Exploratory Trials in PD Long-term Study-1 (NET-PD LS-1) dataset.MethodsThe LS-1 database included 1741 early treated PD subjects (median 4year follow-up). Baseline characteristics were tested for a univariate association with post-baseline falling during the trial. Significant variables were included in a multivariable logistic regression model. A separate analysis using a negative binomial model investigated baseline factors on fall rate.Results728 subjects (42%) fell during the trial, including at baseline. A baseline history of falls was the factor most associated with post-baseline falling. Men had lower odds of post-baseline falling compared to women, but for men, the probability of a post-baseline fall increased with age such that after age 70, men and women had similar odds of falling. Other baseline factors associated with a post-baseline fall and increased fall rate included the Unified PD Rating Scale (UPDRS) Activities of Daily Living (ADL) score, total functional capacity (TFC), baseline ambulatory capacity score and dopamine agonist monotherapy.ConclusionFalls are common in early treated PD. The biggest risk factor for falls in PD remains a history of falling. Measures of functional ability (UPDRS ADL, TFC) and ambulatory capacity are novel clinical risk factors needing further study. A significant age by sex interaction may help to explain why age has been an inconsistent risk factor for falls in PD.

BackgroundThe effects of dopaminergic therapy in parkinson's disease (PD) can vary depending on the class of medication selected.ObjectiveThe aim of this post hoc study was to determine if the class of dopaminergic therapy correlated with disease severity in persons with early, treated PD.MethodsA non-parametric global statistical test (GST) was used to assess the status of participants treated with dopamine agonist (DA) monotherapy, levodopa (LD) monotherapy or combined LD and DA therapy on multiple PD outcomes encompassing motor, cognitive, psychiatric and autonomic function, as well as disability and quality of life.ResultsThe outcomes measured at the beginning of the study showed lower disease burden for participants on initial DA monotherapy compared to those taking combined LD and DA therapy after controlling for age, education, taking cog-meds and amantadine.ConclusionThis observation suggests that clinicians treating early PD patients favor combined LD and DA therapy in patients with more disabling features over DA monotherapy. As such, studies of PD progression in treated PD patients may be affected by the class of symptomatic dopaminergic therapy.

Introduction: Functional magnetic resonance imaging (fMRI) has shown that aging disturbs healthy brain organization and functional connectivity. However, how this age-induced alteration impacts dynamic brain function interaction has not yet been fully investigated. Dynamic function network connectivity (DFNC) analysis can produce a brain representation based on the time-varying network connectivity changes, which can be further used to study the brain aging mechanism for people at different age stages. Method: This presented investigation examined the dynamic functional connectivity representation and its relationship with brain age for people at an elderly stage as well as in early adulthood. Specifically, the resting-state fMRI data from the University of North Carolina cohort of 34 young adults and 28 elderly participants were fed into a DFNC analysis pipeline. This DFNC pipeline forms an integrated dynamic functional connectivity (FC) analysis framework, which consists of brain functional network parcellation, dynamic FC feature extraction, and FC dynamics examination. Results: The statistical analysis demonstrates that extensive dynamic connection changes in the elderly concerning the transient brain state and the method of functional interaction in the brain. In addition, variousmachine learning algorithms have been developed to verify the ability of dynamic FC features to distinguish the age stage. The fraction time of DFNC states has the highest performance, which can achieve a classification accuracy of over 88% by a decision tree. Discussion: The results proved there are dynamic FC alterations in the elderly, and the alteration was found to be correlated withmnemonic discrimination ability and could have an impact on the balance of functional integration and segregation. [ABSTRACT FROM AUTHOR]

Background Esophageal food bolus and/or foreign body (FB) impaction is a common gastrointestinal emergency. This meta-analysis reports on the pooled outcomes of cap-assisted endoscopic removal of esophageal FB. Methods We conducted a comprehensive search of several databases (inception to February 2022) to identify studies reporting on the use of a cap in the endoscopic treatment of esophageal FB ingestion. A random effects model was used to calculate the pooled odds ratio (OR) and mean difference (MD), and I2 values were used to assess the heterogeneity. Results Six studies were analyzed that included 677 patients treated with cap-assisted and 694 with conventional endoscopy. The cap-assisted method demonstrated statistically significant superiority regarding technical success (pooled OR 7.1, 95% confidence interval [CI] 1.9-26.9; P=0.004), en bloc removal (pooled OR 26.6, 95%CI 17.6-40.2; P<0.001), as well as a significantly shorter procedure time (4.6 min, 95%CI -6.5 to -2.8; P<0.001), compared to conventional methods. Better technical success was achieved with the cap-assisted method performed under anesthesia (OR 8.7, 95%CI 1.6-47.7; P=0.01); however, a shorter procedure time was noted for the cap-assisted method without anesthesia (MD -1.5, 95%CI -2.7 to -0.4; P=0.01). Pooled adverse events were comparable. Pooled OR for mucosal tear was significantly lower with cap in food bolus impaction (OR 0.07, 95%CI 0.01-0.38; P=0.02). Conclusion Cap-assisted endoscopic removal of esophageal FB is associated with better technical success and en bloc removal, and a shorter procedure time compared to conventional methods, with comparable adverse events. [ABSTRACT FROM AUTHOR]

Abstract Background About half of Americans 50 to 75 years old do not follow recommended colorectal cancer (CRC) screening guidelines, leaving 40 million individuals unscreened. A simple blood test would increase screening compliance, promoting early detection and better patient outcomes. The objective of this study is to demonstrate the performance of an improved sensitivity blood-based Septin 9 (SEPT9) methylated DNA test for colorectal cancer. Study variables include clinical stage, tumor location and histologic grade. Methods Plasma samples were collected from 50 untreated CRC patients at 3 institutions; 94 control samples were collected at 4 US institutions; samples were collected from 300 colonoscopy patients at 1 US clinic prior to endoscopy. SEPT9 methylated DNA concentration was tested in analytical specimens, plasma of known CRC cases, healthy control subjects, and plasma collected from colonoscopy patients. Results The improved SEPT9 methylated DNA test was more sensitive than previously described methods; the test had an overall sensitivity for CRC of 90% (95% CI, 77.4% to 96.3%) and specificity of 88% (95% CI, 79.6% to 93.7%), detecting CRC in patients of all stages. For early stage cancer (I and II) the test was 87% (95% CI, 71.1% to 95.1%) sensitive. The test identified CRC from all regions, including proximal colon (for example, the cecum) and had a 12% false-positive rate. In a small prospective study, the SEPT9 test detected 12% of adenomas with a false-positive rate of 3%. Conclusions A sensitive blood-based CRC screening test using the SEPT9 biomarker specifically detects a majority of CRCs of all stages and colorectal locations. The test could be offered to individuals of average risk for CRC who are unwilling or unable to undergo colonscopy.

Abstract Background Initial assessment of dyspepsia often includes noninvasive testing for Helicobacter pylori infection. Commercially available tests vary widely in cost and accuracy. Although there is extensive literature on the cost-effectiveness of H. pylori treatment, there is little information comparing the cost-effectiveness of various currently used, noninvasive testing strategies. Methods A Markov simulation was used to calculate cost per symptom-free year and cost per correct diagnosis. Uncertainty in outcomes was estimated using probabilistic sensitivity analysis. Results Under the baseline assumptions, cost per symptom-free year was $122 for empiric proton pump inhibitor (PPI) trial, and costs for the noninvasive test strategies ranged from $123 (stool antigen) to $129 (IgG/IgA combined serology). Confidence intervals had significant overlap. Conclusions Under our assumptions for how testing for H. pylori infection is employed in United States medical practice, the available noninvasive tests all have similar cost-effectiveness between one another as well as with empiric PPI trial.

Abstract Background There is an ongoing debate whether essential tremor (ET) represents a monosymptomatic disorder or other neurologic symptoms are compatible with the diagnosis of ET. Many patients with clinically definite ET develop dystonia. It remains unknown whether tremor associated with dystonia represent a subtype of ET. We hypothesized that ET with dystonia represents a distinct subtype of ET. Methods We studied patients diagnosed with familial ET and dystonia. We included only those patients whose first-degree relatives met diagnostic criteria for ET or dystonia with tremor. This cohort was ascertained for the presence of focal, segmental, multifocal, hemidystonia or generalized dystonia, and ET. Results We included 463 patients from 97 kindreds with autosomal dominant mode of inheritance (AD), defined by the vertical transmission of the disease. ET was the predominant phenotype in every ascertained family and each was phenotypically classified as AD ET. "Pure" ET was present in 365 individuals. Focal or segmental dystonia was present in 98 of the 463 patients; 87 of the 98 patients had ET associated with dystonia, one had dystonic tremor and ten had isolated dystonia. The age of onset and tremor severity did not differ between patients with "pure" ET and ET associated with dystonia. We did not observe a random distribution of dystonia in AD ET pedigrees and all patients with dystonia associated with ET were clustered in 28% of all included pedigrees (27/97, p < 0.001). Conclusions Our results suggest that familial ET associated with dystonia may represent a distinct subtype of ET.