Cognitive Function in Iron Deficient Heart Transplant Recipients Receiving Intravenous Iron Supplement: A Prespecified Secondary Endpoint in the Randomized Ironic Trial

Abstract

<h3>Purpose</h3> Results from previous trials have suggested a decline in cognitive function following heart transplant (HTx). The IronIC trial was a randomized controlled trial, designed to test if ferric derisomaltose could improve exercise capacity in HTx recipients > 1 year after HTx. Cognitive function was a prespecified secondary endpoint. <h3>Methods</h3> HTx recipients with iron deficiency (ID) were randomized to ferric derisomaltose or placebo. ID was defined as ferritin <100μg/l, or ferritin 100-300μg/l in combination with transferrin saturation of <20%, the definition used in heart failure. Core cognitive functions were assessed at baseline and follow-up at 6 months using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Reaction time was measured from a signal was shown to the participant released a button, and from the button was released to the participant pressed a yellow circle (Figure 1). Spatial working memory was assessed as the ability to recall where a token already was found among a given number of boxes, and the strategy used when opening the boxes. Episodic memory was assessed using paired associated learning. Different figures were presented around the screen, and the participants had to recall the placing when the figures were presented in the middle of the screen. <h3>Results</h3> Cognitive functions did not differ significantly between the treatment arms(Table 1). <h3>Conclusion</h3> Intravenous iron supplement did not improve cognitive functions in HTx recipients with ID defined as in heart failure.