What is the minimum amount of folic acid that improves blood vessel function in children with type 1 diabetes?

What is the minimum dose of folic acid that improves vascular health in children with type 1 diabetes?

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12610000176066

Enrollment

Registered

2010-02-25

Start date

2010-03-20

Completion date

2010-10-02

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Children with type 1 diabetes have detectable arterial endothelial dysfunction and arterial intima-media thickening as first markers of accelerated atherosclerosis. They can be reliably measured to test the effectiveness of early intervention strategies. Folic acid supplementation significantly reduces the risk of stroke in adults, with most benefit in primary prevention. We have demonstrated that folic acid supplementation 5 mg daily rapidly normalizes endothelial function in children with type 1 diabetes, independent of homocysteine lowering. However there are no dose response studies of the benefit of folic acid to determine the minimum effective dose. This is relevant as while high dose folic acid does not have short term adverse effects, recent epidemiological data questions its long term safety in individuals with established vascular or early neoplastic disease. Determining the minimum dose of folic acid that improves endothelial function and the effect of endothelial nitric oxide synthase polymorphisms on the response to folic acid, will also inform future intervention trials for accelerated atherosclerosis in this age group.

Interventions

Randomised double blind crossover placebo controlled trial. Intervention consists of folic acid, in one of the three doses available (0.5mg, 2mg or 5mg), as a single dose only (10ml), administered orally, in a random order. The duration between interventions is 4 weeks.

Study design

Allocation

Randomised controlled trial

Intervention model

Crossover

Primary purpose

Prevention

Masking

Blinded (masking used)

Eligibility

Sex/Gender

All

Age

10 Years to 16 Years

Healthy volunteers

Inclusion criteria

Type 1 diabetes of longer than 1 year duration (attending the Diabetes clinic at Women's and Children's Hospital, Adelaide)

Exclusion criteria

History of smoking or serum cotinine level >28 nmol/l; Coeliac disease, screened by transglutaminase immunoglobulin A (IgA); Treatment with statins or angiotensin converting enzyme inhibitors; Vitamin supplementation; Vitamin B12 deficiency; Intercurrent illness or ketosis at the time of the study.

Outcome results