In the news: Omega-3 May Benefit Statin Users; Vitamin D Cuts Risk of Asthma Attacks

FH: A Genetic Form of High Blood Cholesterol

Familial hypercholesterolemia (called FH) is a genetic condition in which the body is unable to efficiently remove LDL cholesterol from the bloodstream. This inherited form of high cholesterol results in greatly elevated LDL levels, as well as a higher risk of atherosclerosis and heart attack at an early age.

Those who inherit two copies of the defective FH gene (one from each parent) can develop cardiovascular disease during childhood. The more common form of FH, where only one copy of the abnormal gene is inherited from a parent, can lead to premature cardiovascular disease – often at 30-40 years of age.

The more common form of FH is usually treated with statins or other lipid lowering drugs that reduce blood cholesterol levels. Though statin therapy can help lower the risk of atherosclerosis, some cardiovascular risks still remain.

One of those risks is a reduction in the elasticity of arteries – a risk that is considered a predictor of future coronary heart disease. It’s important for vessels to be supple and elastic so that they can expand and contract continuously as blood pulses through them.

Omega-3s May Add Heart Benefits for Statin Users with FH

To evaluate whether omega-3 fatty acids might improve artery stiffness and other risk factors, Australian researchers conducted a trial in 20 FH patients who were already taking statins (1).

The participants were randomly assigned to receive 4 grams of omega-3 fatty acids daily (1,840 mg EPA and 1,520 mg DHA) or no supplements for 8 weeks. After another 8 weeks of ‘washout’, the patients switched to the other group for an additional 8-week period.

Omega-3 supplementation showed a significant, 9% improvement in elasticity for large (though not small) arteries. Blood pressure was also reduced (6% reduction in both diastolic and systolic pressures) in the omega-3 group. Additionally, triglycerides dropped 20% and an 8% reduction was seen in levels of Apolipoprotein B – a protein component of LDL cholesterol that transports cholesterol to tissues.

The authors conclude that supplemental omega-3s improved artery stiffness, blood pressure and other risk factors in these FH patients, independent of statin therapy. They believe that the improvements seen in blood vessel elasticity are likely due to a direct effect of the omega-3s on the artery wall.

Vitamin D Cuts Risk of Severe Asthma Attacks

Low blood levels of vitamin D have been linked to an increased risk of asthma attacks in children and adults with asthma. Several clinical trials have evaluated whether vitamin D might prevent asthma attacks and improve control of asthma symptoms.

Now, a major review by the Cochrane group has analyzed the high quality trials that have been conducted, and concluded that vitamin D (taken with standard asthma drugs) can reduce the risk of severe asthma attacks (2). Cochrane reviews are considered to be the highest standard in evidence-based information for health care providers.
 
The analysis, which included 7 trials involving nearly 1,100 children and adults with mild to moderate asthma, found that the risk of having severe attacks was cut in half (from 6% to 3%) with vitamin D supplementation. The rate of attacks requiring steroid treatment was significantly reduced as well.

While the reviewers found a benefit in preventing attacks, they did not find an improvement in everyday symptoms in patients taking asthma medications. It’s still unclear whether the vitamin just helps those who have low vitamin D levels, or all those who suffer severe attacks. The reviewers are working on a second analysis to help answer this question.

References

1. Chan DH, et al. Effect of omega-3 fatty acid supple-mentation on arterial elasticity in patients with familial hypercholesterolemia on statin therapy. Nutrition, Metabolism, and Cardiovascular Disease. Epub ahead of print, Aug. 3, 2016.
2. Martineau AR, et al. Vitamin D for the management of asthma. Cochrane Databse Syst Rev. Epub ahead of print, Sept. 5, 2016.