Background:

Chronic heart failure is a debilitating condition that accounts for an annual NHS spend of £2.3B. Low levels of endogenous coenzyme Q10 may exacerbate chronic heart failure. Coenzyme Q10 supplements might improve symptoms and slow progression. As statins are thought to block the production of coenzyme Q10, supplementation might be particularly beneficial for patients taking statins.

Objectives:

To assess the clinical effectiveness and cost-effectiveness of coenzyme Q10 in managing chronic heart failure with a reduced ejection fraction.

Methods:

A systematic review that included randomised trials comparing coenzyme Q10 plus standard care with standard care alone in chronic heart failure. Trials restricted to chronic heart failure with a preserved ejection fraction were excluded. Databases including MEDLINE, EMBASE and CENTRAL were searched up to March 2020. Risk of bias was assessed using the Cochrane Risk of Bias tool (version 5.2). A planned individual participant data meta-analysis was not possible and meta-analyses were mostly based on aggregate data from publications. Potential effect modification was examined using meta-regression. A Markov model used treatment effects from the meta-analysis and baseline mortality and hospitalisation from an observational UK cohort. Costs were evaluated from an NHS and Personal Social Services perspective and expressed in Great British pounds at a 2019/20 price base. Outcomes were expressed in quality-adjusted life-years. Both costs and outcomes were discounted at a 3.5% annual rate.

Results:

A total of 26 trials, comprising 2250 participants, were included in the systematic review. Many trials were reported poorly and were rated as having a high or unclear risk of bias in at least one domain. Meta-analysis suggested a possible benefit of coenzyme Q10 on all-cause mortality (seven trials, 1371 participants; relative risk 0.68, 95% confidence interval 0.45 to 1.03). The results for short-term functional outcomes were more modest or unclear. There was no indication of increased adverse events with coenzyme Q10. Meta-regression found no evidence of treatment interaction with statins. The base-case cost-effectiveness analysis produced incremental costs of £4878, incremental quality-adjusted life-years of 1.34 and an incremental cost-effectiveness ratio of £3650. Probabilistic sensitivity analyses showed that at thresholds of £20,000 and £30,000 per quality-adjusted life-year coenzyme Q10 had a high probability (95.2% and 95.8%, respectively) of being more cost-effective than standard care alone. Scenario analyses in which the population and other model assumptions were varied all found coenzyme Q10 to be cost-effective. The expected value of perfect information suggested that a new trial could be valuable.

Limitations:

For most outcomes, data were available from few trials and different trials contributed to different outcomes. There were concerns about risk of bias and whether or not the results from included trials were applicable to a typical UK population. A lack of individual participant data meant that planned detailed analyses of effect modifiers were not possible.

Conclusions:

Available evidence suggested that, if prescribed, coenzyme Q10 has the potential to be clinically effective and cost-effective for heart failure with a reduced ejection fraction. However, given important concerns about risk of bias, plausibility of effect sizes and applicability of the evidence base, establishing whether or not coenzyme Q10 is genuinely effective in a typical UK population is important, particularly as coenzyme Q10 has not been subject to the scrutiny of drug-licensing processes. Stronger evidence is needed before considering its prescription in the NHS.

Future work:

A new independent, well-designed clinical trial of coenzyme Q10 in a typical UK heart failure with a reduced ejection fraction population may be warranted.

Study registration:

This study is registered as PROSPERO CRD42018106189.

Funding:

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 4. See the NIHR Journals Library website for further project information.

Article history

The research reported in this issue of the journal was funded by the HTA programme as project number 17/12/02. The contractual start date was in September 2018. The draft report began editorial review in October 2020 and was accepted for publication in April 2021. The authors have been wholly responsible for all data collection, analysis and interpretation, and for writing up their work. The HTA editors and publisher have tried to ensure the accuracy of the authors’ report and would like to thank the reviewers for their constructive comments on the draft document. However, they do not accept liability for damages or losses arising from material published in this report.