Gastrointestinal Microbiome, Atherosclerosis, Nutrients, Renal Function
Conditions
Keywords
intestinal microbiome, atherosclerosis, nutrients, renal function
Brief summary
Patients attending stroke prevention clinics and a premature atherosclerosis clinic at University Hospital in London, ON, Canada were recruited to the study. They completed a dietary questionnaire, provided stool samples and had blood drawn to measure plasma levels of metabolites produced by the intestinal bacteria.
Detailed description
Patients were phenotyped by their residual score in linear multiple regression with measured carotid plaque burden as the dependent variable and coronary risk factors were predictors. The residual score essentially represents the distance off the regression line of predicted plaque. They were grouped into three categories: Unexplained atherosclerosis (with more plaque than predicted by risk factors; residual score \>2); Explained (the amount of plaque predicted by risk factors, residual score \>-2 and \<2); and Protected (less plaque than predicted by risk factors, residual score \<-2). DNA was extracted from stool samples in the lab of Dr. Allen-Vercoe at University of Guelph. RNA makeup of the intestinal microbiome was assessed in the lab of Dr. Gregory Gloor at Western. Plasma levels of trimethylamine n-oxide, p-cresylsulfate, hippuric acid, p-cresyl glucuronide, pheny acetyl glutamine and phenyl sulfate were measured by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry in the lab of Dr. Bradley Urquhart at Western. Nutrient intake over the past year was calculated at the Harvard School of Public Health from the 131 item self-reported and semi-quantitative Harvard Food Frequency Questionnaire (FFQ). Estimated glomerular filtration rate was calculated from the Chronic Kidney Disease Epidemiological (CKD-EPI) equations.
Interventions
DIAGNOSTIC_TESTPlasma levels of metabolites
plasma levels of metabolites
BEHAVIORALDietary questionnaire
Harvard food frequency questionnaire
DIAGNOSTIC_TESTIntestinal microbiome
amplification and sequencing of 16S rRNA gene variable regions in stool samples
Sponsors
London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients attending stroke prevention clinics and a Premature Atherosclerosis Clinic at University Hospital, London, ON, Canada, * with measurements of carotid plaque burden and the risk factors used in the linear regression model. * Willing to consent to the protocol approved by the Ethics board
Exclusion criteria
* Missing data on variables used in the regression model,
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Plasma levels of metabolites in the three phenotypes | Day 1 | Plasma levels of trimethylamine n-oxide, p-cresylsulfate, hippuric acid, p-cresyl glucuronide, pheny acetyl glutamine and phenyl sulfate |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Bacterial profile of the intestinal microbiome | Day 1 | Amplification and sequencing of 16S rRNA gene variable regions |
| Effect of nutrient intake on plasma levels of metabolites | Day 1 | Nutrient analysis from food frequency questionnaire |
| Effect of renal function on plasma levels of metabolites | Day 1 | eGFR from CKD-EPI equations |
Countries
Canada
Outcome results
None listed