Determinants of Adherence to a Ketogenic Diet in Patients with Heart Failure with Reduced Ejection Fraction

Background: Dietary interventions in heart failure (HF) remain limited, with current guidance focused largely on sodium restriction. Ketone metabolism has emerged as a potential therapeutic target in HF, with ketone supplementation shown to improve cardiac function. However, there are currently no studies investigating factors affecting adherence to a ketogenic diet (KD) in HF. Aim: To explore the factors influencing adherence to a KD in patients with HF to inform future dietary interventions. Method: This qualitative study was embedded within the KETO-HF pilot randomised controlled trial, in which participants with HF with reduced ejection fraction undertook a 4-month KD. Consenting participants were invited to complete semi-structured interviews. Interviews were audio-recorded, deidentified and transcribed verbatim. Data were analysed using thematic analysis with a mixed inductive-deductive strategy. Results: Fifteen participants were interviewed. Facilitators of adherence were: (1) personal motivation and self-regulation; (2) improved well-being; (3) interpersonal support and; (4) adaptive strategies and improved nutritional literacy. Barriers included: (1) early-phase physiological and psychological challenges; (2) social and cultural friction; (3) competing family and work demands and; (4) limited availability of suitable foods, particularly difficulty managing social situations and dining out. Conclusions: Adherence to a KD in people with HF is shaped by a combination of individual and social factors. These findings highlight the need for improved education, support, and increased food options to optimise implementation of dietary ketosis in HF.