Peritoneal Dialysis (PD) is a technique for treating kidney failure where fluid is instilled into the body's peritoneal cavity. Fluid and solutes travel across the peritoneum, and this is critical to successful PD. Studies have shown that certain demographic and clinical variables explain a small part of the variability in baseline peritoneal solute transfer rate and water transfer function across the peritoneum. This study sought to identify the common genetic variants associated with the baseline peritoneal function in patients starting treatment with PD and change in function upon treatment with PD. This study has two specific aims: Aim 1: To identify and validate genetic loci that influence the peritoneal solute transfer rate (PSTR) at start of PD. Aim 2: To identify and validate genetic loci in pre-specified biologic pathways with change in peritoneal ultrafiltration capacity. This study incorporates data from participants' peritoneal solute transfer rate in their first ever peritoneal equilibrium test (PET) and changes in the transfer of water across the peritoneal membrane over time in a sub-group of participants, demographic information, and results from laboratory analysis of DNA, blood, and dialysate. This study comprises patient populations from pre-existing biorepositories in Europe, and prospectively enrolled participants in United States, Canada, United Kingdom, and Australia. Clinical data related to the participants' peritoneal solute transfer rate from their first ever Peritoneal Equilibrium Test (PET), demographic information, and change in ultrafiltration capacity over time, are correlated with various genetic markers of interest. For individuals enrolled prospectively, blood and dialysate were collected at the first study visit. Annually, subjects either underwent a PET as standard of care or perform an additional 4-hour dwell as part of the study. These subsequent measures were utilized to determine change in ultrafiltration capacity over time. Inclusion criteria included adults over the age of 20 who are able to provide consent and had a record of a PET within 6 months of starting PD. Subjects with missing outcome data and that did not pass genotyping QC were excluded. Genotyping was performed in two batches using the Illumina InfiniumOmni2-5-8v1-3_A1 array with 2,372,784 single nucleotide variants (SNVs) in the first batch (n=1957). The second genotyping batch (n=1053) was on the InfiniumOmni2-5-8v1-4_A1 array with 2,382,209 SNVs. Imputation was performed using the Michigan Imputation Server and the HRC1.1 genotype reference. The Institutional Review Board of the University of Washington has “dbGaP-certified” the consent forms used to enroll participants in Australia, Canada, and United States and the genotype-phenotype data from the participants (n=827) deposited in the public repository. Furthermore, it has been determined that under the EU-GDPR regulations, depositing data of participants enrolled in UK, Belgium, and Sweden (n=2,023) into dbGaP “serves no lawful purpose” as the consent form used for enrolling participants did not obtain explicit permission for depositing data in a public repository.
Summary of the Design and Aims: The Coagulation and Fibrinolysis in a Pediatric Insulin Titration Trial (CAF-PINT) is an ancillary study to the HALF PINT (NCT01565941) randomized, controlled trial that was originally designed to study changes in inflammatory and thrombosis pathways in the setting of an interventional trial. The parent HALF PINT study was designed to study the impact of tight glycemic control (TGC) using an explicit insulin titration algorithm to safely achieve a normal glucose in target range of 80-110 mg/dL versus 150-180mg/dL on clinical outcomes among critically ill hyperglycemic children with Heart and Lung Failure. The CAF PINT study collected blood samples pre randomization and at 2 and 4 days after randomization. Blood samples collected in EDTA tubes were centrifuged at local sites to separate the plasma from cell pellets and frozen prior to shipment. In addition, 0.5 mL of whole blood collected in PAXgene tubes modified for use in pediatrics frozen 24 hours after collection prior to shipment.Population Information: Setting: Twenty-one academic children's hospitals (HALF-PINT) and 1 academic children's hospital (IIT-SBPP). Participants: Critically ill hyperglycemic children requiring mechanical ventilation/vasoactive support (n=293).Interventions and Exposures: Patients in HALF PINT were randomized to achieve a low target glucose (80-110 mg/dL) vs. a higher target (150-180 mg/dL). The primary trial was stopped early due to low likelihood of achieving a statistically significant difference in the primary outcomes. Molecular Technologies Employed: Plasma biomarkers were assayed on thawed plasma using a Luminex panel. RNA was extracted from PAXgene Blood RNA Kits modified for pediatric use. Extracted RNA was sequenced with the Novaseq S4 system (Illumina) to generate 2 x 150 base paired end reads to a target depth of 50 million read-pairs per sample.Principal Findings of the Study: We tested for heterogeneity of treatment effects according to baseline blood inflammatory proteins using logistic regression with individual biomarkers as interaction terms and Cox regression analysis using biomarker-derived latent classes. Children with higher inflammatory proteins including TNFR-1, IL-6, IL-8, and IL-10 had lower mortality when treated with insulin to a target glucose of 80-110 mg/dL as compared to 150-180 mg/dL (interaction p<0.05). Causal forest estimates ranged from a 40% mortality reduction to a 15% mortality increase with TGC, depending on each patient’s individual biomarker profile. Latent class categorization strongly interacted with TGC with respect to mortality (Cox regression interaction p=0.005). Specifically, patients with higher inflammation benefited from TGC (6% mortality with TGC vs. 48% mortality, p=0.004) whereas hypoinflamed patients showed a trend towards harm (14% mortality with TGC vs. 7% mortality, p=0.055).Data available through dbGaP: Transcriptomic (Gene Counts) and phenotype data
Himalayan population genetic study raw data (Tibet)
Himalayan population genetic study raw data (Himalaya)
ARID1B+/+ (control) and ARID1B+/- human telencephalic organoids at D120
