Cardiorespiratory Fitness Mediates Cognitive Performance in Chronic Heart Failure Patients and Heart Transplant Recipients

• Main Authors: Florent Besnier, Béatrice Bérubé, Christine Gagnon, Miloudza Olmand, Paula Aver Bretanha Ribeiro, Anil Nigam, Martin Juneau, Lucie Blondeau, Michel White, Vincent Gremeaux, Louis Bherer, Mathieu Gayda
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: heart failure; heart transplant; cardiorespiratory fitness; cognition
• Online Access: https://www.mdpi.com/1660-4601/17/22/8591
• ISSN: 1661-7827; 1660-4601

We compared cognitive profiles in chronic heart failure patients (HF), heart transplant recipients (HT) and healthy controls (HC) and examined the relationship between cardiorespiratory fitness (<inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak), peak cardiac output (CO_peak) and cognitive performance. Stable HT patients (<i>n</i> = 11), HF patients (<i>n</i> = 11) and HC (<i>n</i> = 13) (61.5 ± 8.5 years) were recruited. Four cognitive composite scores targeting different cognitive functions were computed from neuropsychological tests: working memory, processing speed, executive functions and verbal memory. Processing speed and executive function scores were higher, which indicates lower performances in HF and HT compared to HC (<i>p</i> < 0.05). <inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak and first ventilatory threshold (VT₁) were lower in HF and HT vs. HC (<i>p</i> < 0.01). CO_peak was lower in HF vs. HT and HC (<i>p</i> < 0.01). Processing speed, executive function and verbal memory performances were correlated with <inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak, VT₁ and peak cardiac hemodynamics (<i>p</i> < 0.05). Mediation analyses showed that <inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak and VT₁ mediated the relationship between group and processing speed and executive function performances in HF and HT. CO_peak fully mediated executive function and processing speed performances in HF only. <inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak and CO_peak were related to cognitive performance in the entire sample. In addition, <inline-formula><math display="inline"><semantics><mover accent="true"><mi>V</mi><mo>˙</mo></mover></semantics></math></inline-formula>O_2peak and VT₁ fully mediated the relationship between group and executive function and processing speed performances.