Coenzyme Q10 — Heart Energy After 50?

Aim of the study: Healthy dietary patterns are rich in micronutrients, but their influence on cardiovascular disease (CVD) risks has not been systematically quantified. The goal of this study was to provide a comprehensive and most up-to-date evidence-based map that systematically quantifies the impact of micronutrients on CVD outcomes.

Results: A total of 884 randomized controlled intervention trials evaluating 27 types of micronutrients among 883,627 participants (4,895,544 person-years) were identified. Supplementation with n-3 fatty acid, n-6 fatty acid, l-arginine, l-citrulline, folic acid, vitamin D, magnesium, zinc, α-lipoic acid, coenzyme Q10, melatonin, catechin, curcumin, flavanol, genistein, and quercetin showed moderate- to high-quality evidence for reducing CVD risk factors. Specifically, n-3 fatty acid supplementation decreased CVD mortality (relative risk [RR]: 0.93; 95% CI: 0.88-0.97), myocardial infarction (RR: 0.85; 95% CI: 0.78-0.92), and coronary heart disease events (RR: 0.86; 95% CI: 0.80-0.93). Folic acid supplementation decreased stroke risk (RR: 0.84; 95% CI: 0.72-0.97), and coenzyme Q10 supplementation decreased all-cause mortality events (RR: 0.68; 95% CI: 0.49-0.94). Vitamin C, vitamin D, vitamin E, and selenium showed no effect on CVD or type 2 diabetes risk.

Aim of the study: According to the World Health Organization (WHO), cardiovascular disease is the leading cause of death worldwide. Heart failure has been defined as a global pandemic leading to millions of deaths.

Results: A PubMed search for the terms "ubiquinone" and "ubiquinol" was conducted, and 28 clinical trials were included. Our findings go along with the biochemical description of CoQ10 and CoQH2, recording cardiovascular benefits for CoQ10 and antioxidative and anti-inflammatory properties for CoQH2. Our main outcomes are the following: (I) CoQ10 supplementation reduced cardiovascular death in patients with heart failure. This is not reported for CoQH2. (II) Test concentrations leading to cardiovascular benefits are much lower in CoQ10 studies than in CoQH2 studies. (III) Positive long-term effects reducing cardiovascular mortality are only observed in CoQ10 studies. Based on the existing literature, the authors recommend CoQ10 instead of CoQH2 to treat and prevent cardiovascular disease in patients with heart failure.

Aim of the study: A short review is given of the potential role of selenium deficiency and selenium intervention trials in atherosclerotic heart disease. Selenium is an essential constituent of several proteins, including the glutathione peroxidases and selenoprotein P.

Results: Ischemic heart disease and heart failure are two conditions where increased oxidative stress has been convincingly demonstrated. Some of the intervention studies of anti-oxidative substances that have focused on selenium are discussed in this review. The interrelationship between selenium and coenzyme Q10, another anti-oxidant, is presented, pointing to a theoretical advantage in using both substances in an intervention if there are deficiencies within the population. Clinical results from an intervention study using both selenium and coenzyme Q10 in an elderly population are discussed, where reduction in cardiovascular mortality, a better cardiac function according to echocardiography, and finally a lower concentration of the biomarker NT-proBNP as a sign of lower myocardial wall tension could be seen in those on active treatment, compared to placebo.

Aim of the study: Nutraceuticals are pharmacologically active substances extracted from vegetable or animal food and administered to produce health benefits. We recently reviewed the current evidence for nutraceuticals in patients diagnosed with heart failure as part of the writing of the Australian Guidelines for the prevention, diagnosis, and management of heart failure.

Results: Forty studies met the inclusion criteria. The strongest evidence came from studies of polyunsaturated fatty acids, which modestly decreased mortality and cardiovascular hospitalizations in patients with mostly New York Heart Association class II and III heart failure across a range of left ventricular ejection fraction. Coenzyme Q10 may decrease mortality and hospitalization, but definite conclusions cannot be drawn. Studies that examined nitrate-rich beetroot juice, micronutrient supplementation, hawthorn extract, magnesium, thiamine, vitamin E, vitamin D, L-arginine, L-carnosine, and L-carnitine were too small or underpowered to properly appraise clinical outcomes. Only one nutraceutical, omega-3 polyunsaturated fatty acid, received a positive recommendation in the Australian heart failure guidelines. Although occasionally showing some promise, all other nutraceuticals are inadequately studied to allow any conclusion on efficacy.

Aim of the study: The literature concerning the importance of coenzyme Q10 in health and disease has been reviewed. Usual dietary intake together with normal in vivo synthesis seems to fulfil the demands for Q10 in healthy individuals.

Results: In different cardiovascular diseases, including cardiomyopathy, relatively low levels of Q10 in myocardial tissue have been reported. Positive clinical and haemodynamic effects of oral Q10 supplementation have been observed in double-blind trials, especially in chronic heart failure. These effects should be further examined. No important adverse effects have been reported from experiments using daily supplements of up to 200 mg Q10 for 6-12 months and 100 mg daily for up to 6 y.