Clinical trial NCT04948086: Blood Pressure and Central Haemodynamics in Healthy Adults Stratified by MTHFR Genotype
Official title: Blood Pressure Lowering Effect of B-vitamins in Adults With a Genetic Pre-disposition to Elevated Blood Pressure.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Blood Pressure
Keywords: Blood Pressure
MTHFR
Methylenetetrahydrofolate Reductase
Central Hemodynamics
Riboflavin
Folic Acid
Folate Polymorphism
Lead sponsor: University of Ulster
Sponsor class: OTHER
First posted: 2021-07-01
Enrollment: 498
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Community sample

Brief summary: Approximately 12% of the world's population have a have a common C677T polymorphism in the gene encoding the folate metabolising enzyme, methylenetetrahydrofolate reductase (MTHFR). Homozygosity for the polymorphism (TT genotype) appears to result in an increased requirement for the B-vitamins folic acid and riboflavin and more importantly results in an increased risk of developing high blood pressure (BP). Previous work from our Centre has demonstrated significantly higher BP in those with the TT genotype. This work has been conducted in cohorts with premature cardiovascular disease (CVD) and hypertension without overt CVD, but the effect in younger, healthier individuals is unexplored. To date our studies have also focused on BP as the primary outcome, but newer markers of vascular health including central pressure and hemodynamics have emerged as superior prognostic indicators of CVD. The effect of the TT genotype on these measures is thus an important area for investigation and may help us understand the mechanism linking the genotype with BP, which is currently unknown. As adults with the TT genotype appear to have increased requirements for riboflavin and folic acid, and BP in TT adults appears to be riboflavin dependent, the influence of these vitamins on central measures is an area for consideration. Study Design This is an observational study investigating the blood pressure profiles of healthy adults aged 18-65 years, stratified by MTHFR genotype. Apparently healthy adults will be recruited from workplaces and the general community across Northern Ireland and screened for the polymorphism via buccal swab. Those with the TT genotype and a similar number of non-TT (i.e. CC/CT) genotype individuals will be contacted and asked to come to attend a one-off appointment. Brachial BP will be assessed by an electronic BP monitor, central BP and central haemodynamics (augmentation index, augmentation pressure and pulse wave velocity) will be assessed by SphygmoCor XCEL. In addition, anthropometric measurements, health and lifestyle information and a blood sample will be obtained. Data will be statistically analysed using SPSS software to if determine differences between gentoype groups exist.


Eligibility criteria: Inclusion Criteria:

* Pre-screened for MTHFR 677TT genotype
* Aged at least 18 years old

Exclusion Criteria:

* Younger than 18 years
* Pregnant

Primary outcomes:
measure: Blood pressure
timeFrame: One day, one measurement
Secondary outcomes:
measure: Brachial blood pressure
timeFrame: One day, one measurement
measure: Central blood pressure
timeFrame: One day, one measurement
measure: Pulse wave analysis
timeFrame: One day, one measurement
measure: Pulse wave velocity
timeFrame: One day, one measurement
measure: Riboflavin status
timeFrame: One day, one measurement
measure: Folate status
timeFrame: One day, one measurement
measure: PLP status
timeFrame: One day, one measurement
measure: Homocysteine status
timeFrame: One day, one measurement
measure: One-carbon metabolite status
timeFrame: One day, one measurement
Other outcomes:
Locations:
city: Coleraine
country: United Kingdom
facility: Human Intervention Studies Unit, Ulster University
state: Co.Londonderry
Study officials:
References: