Clinical trial NCT03398889: Intestinal Microbiome and Extremes of Atherosclerosis
Official title: Intestinal Microbiome and Extremes of Atherosclerosis
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Gastrointestinal Microbiome, Atherosclerosis, Nutrients
Renal Function
Keywords: intestinal microbiome
atherosclerosis
nutrients
renal function
Lead sponsor: London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Sponsor class: OTHER
First posted: 2018-01-16
Enrollment: 316
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: PROBABILITY_SAMPLE
Study population: as above

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.

Eligibility criteria: 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,

Primary outcomes:
measure: Plasma levels of metabolites in the three phenotypes
timeFrame: Day 1
Secondary outcomes:
measure: Bacterial profile of the intestinal microbiome
timeFrame: Day 1
measure: Effect of nutrient intake on plasma levels of metabolites
timeFrame: Day 1
measure: Effect of renal function on plasma levels of metabolites
timeFrame: Day 1
Other outcomes:
Locations:
city: London
country: Canada
facility: Stroke Prevention & Atherosclerosis Research Centre
state: Ontario
Study officials:
References: