Heart Failure, Heart Failure and Reduced Ejection Fraction, Heart Failure and Mildly Reduced Ejection Fraction, Heart Failure and Preserved Ejection Fraction, Selenium Supplementation, Selenium, Cognitive Functioning
Conditions
Keywords
heart failure, selenium, RRCT, SIRI-HF
Brief summary
Heart failure is a serious condition in which the heart is unable to pump blood effectively, and it remains a leading cause of hospitalization and death worldwide despite advances in treatment. Selenium is an essential micronutrient that plays an important role in cellular energy production, antioxidant defense, and overall cardiovascular function. Low selenium levels are common among patients with heart failure in Northern Europe, and observational studies have shown that selenium deficiency is associated with an increased risk of hospitalization and death. In cases of severe deficiency, such as in Keshan disease, heart dysfunction can be reversed with selenium supplementation, suggesting a potential causal relationship. However, it is not yet known whether selenium supplementation can improve clinical outcomes in patients with heart failure when added to standard medical therapy. The SIRI-HF trial is a randomized, placebo-controlled study designed to evaluate whether daily supplementation with 200 micrograms of selenium, in addition to guideline-directed medical therapy, improves outcomes in patients with heart failure. The primary endpoint is a composite of recurrent heart failure hospitalizations and cardiovascular death. Secondary endpoints include all-cause mortality, changes in symptoms and functional status, and safety outcomes. This study will include patients from Sweden and Norway and aims to determine whether correcting selenium deficiency can improve prognosis in heart failure.
Detailed description
Heart failure (HF) is a complex, systemic syndrome characterized not only by impaired cardiac function but also by metabolic, inflammatory, and neurohormonal disturbances. Despite advances in guideline-directed medical therapy, patients with HF continue to experience high rates of hospitalization and mortality, highlighting the need for additional therapeutic strategies. Selenium is an essential trace element incorporated into selenoproteins that play key roles in redox regulation, mitochondrial function, immune modulation, and thyroid hormone metabolism. Observational data from European populations, where dietary selenium intake is relatively low, have demonstrated associations between low selenium status and increased risk of incident HF, impaired functional capacity, reduced quality of life, and higher mortality. Mechanistically, selenium deficiency may contribute to impaired mitochondrial oxidative phosphorylation, increased oxidative stress, and cardiomyocyte dysfunction. While prior randomized studies of selenium supplementation have yielded mixed results, these have largely been conducted in populations with adequate baseline selenium levels or have not specifically targeted patients with HF. Smaller studies and subgroup analyses suggest potential benefits on cardiac function and clinical outcomes, but definitive evidence is lacking. The SIRI-HF trial is designed to address this evidence gap using a pragmatic, registry-based randomized clinical trial (RRCT) design. The study is embedded within established national heart failure registries in Sweden (SwedeHF) and Norway (NHFR), enabling large-scale recruitment and efficient long-term follow-up through linkage with national healthcare and administrative registries. This approach allows for comprehensive capture of clinical events, including hospitalizations and mortality, in a real-world setting. A total of 4,326 adult patients with a diagnosis of heart failure will be randomized in a 1:1 ratio to receive either oral selenium supplementation (200 µg daily) or matching placebo, in addition to standard care. The trial is double-blind, with participants, investigators, and outcome assessors masked to treatment allocation. Recruitment is planned over approximately four years, with follow-up extending up to five years depending on enrollment timing. The study is conducted using a largely remote design. Eligible patients are identified through registry data and invited to participate via digital or postal consent procedures. Study treatment is distributed directly to participants, and follow-up includes periodic electronic questionnaires assessing symptoms, adherence, and quality of life. Clinical outcomes are ascertained through linkage with national registries, minimizing the need for in-person visits and reducing loss to follow-up. The primary endpoint is the total number of heart failure hospitalizations and cardiovascular deaths, analyzed as recurrent events over the follow-up period. Secondary endpoints include time-to-event outcomes such as first heart failure hospitalization or cardiovascular death, as well as individual components including cardiovascular mortality and all-cause mortality. Additional exploratory outcomes include broader cardiovascular events, unscheduled hospitalizations, incident dementia, and changes in patient-reported health status measured by the Kansas City Cardiomyopathy Questionnaire. A predefined mechanistic sub-study will be conducted in a subset of participants to evaluate the effects of selenium supplementation on cardiac structure and function, biomarkers, functional capacity, and biochemical measures of selenium status. The registry-based design, large sample size, and integration with national health data systems are expected to provide robust and generalizable evidence regarding the effect of selenium supplementation on clinically relevant outcomes in patients with heart failure.
Interventions
Selenium will be provided as the Bio-SelenoPrecise supplement. Each Bio-SelenoPrecise tablet contains 200 μg of selenium in the form of the yeast-based compound SelenoPrecise yeast. The tablets also include excipients such as microcrystalline cellulose, dicalcium phosphate, crosscarmellose sodium, silica, magnesium stearate, and is coated with hydroxypropyl methylcellulose
Placebo tablet identical to active comparator
Sponsors
Study design
Intervention model description
This study is an investigator-initiated, pragmatic, double-blinded, placebo-controlled, randomized trial, designed to evaluate the effects of selenium versus placebo in reducing the composite of number of HF hospitalizations and/or CV death among patients with HF. The trial will employ a registry-based approach to maximize efficiency and relevance to real-world settings. A number of 4326 participants will be randomized in 1:1 fashion (2163 per arm). Eligible participants will be identified through the SwedeHF Registry, which will also serve as a primary tool for data collection, alongside the Swedish National Board of Health and Welfare and National Cause of Death Register in Sweden. In Norway, NHFR will be used to recruit patients and Helsedirektoratet will be used to retrieve follow-up data. These registries will capture essential baseline information and follow-up data throughout the study.
Eligibility
Inclusion criteria
To be considered for inclusion in this study, patients must meet all of the following eligibility requirements: * 18 years of age * primary discharge diagnosis of HF coded as ICD-10: I50, as recorded in The SwedeHF registry * be able to provide documented informed consent by signing and dating the designated consent form.
Exclusion criteria
* Not suitable in the opinion of the Investigator (for example due to severe or terminal comorbidity with poor prognosis, or characteristics, pregnancy etc.) that may interfere with adherence to trial protocol
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of HF hospitalizations and/or CV mortality in heart failure patients. | Recruitment over 4 years, followed by an additional year of observation, resulting in an average follow-up of 3 years, with an adaptive component allowing for an interim analysis to evaluate accrued data and adjust the study duration if necessary | The primary objective is to assess whether supplementation with selenium compared to placebo reduces the number of HF hospitalizations and/or CV mortality in HF patients. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of major adverse cardiovascular events | Recruitment over 4 years, followed by an additional year of observation, resulting in an average follow-up of 3 years, with an adaptive component allowing for an interim analysis to evaluate accrued data and adjust study duration if necessary. | \- Major adverse CV events (MACE), defined as a combination of hospitalization for HF, stroke, acute myocardial infarction, or CV death. |
| Time to a composite event of first hospitalization for HF or CV death | Recruitment over 4 years, followed by an additional year of observation, resulting in an average follow-up of 3 years, with an adaptive component allowing for an interim analysis to evaluate accrued data and adjust the study duration if necessary | Secondary objectives of the study are (i) time to a composite event of first hospitalization for HF or CV death, both defined as in the primary endpoint, |
Countries
Norway, Sweden