Aims: The risk of heart failure (HF) increases with BMI, but paradoxically obesity has been associated with reduced mortality in patients with HF. The effect of intentional or therapeutic weight loss on HF is not well known. We examined the effect of weight loss induced by low energy diet (LED) on physical performance and cardiovascular risk factors in obese patients with moderate-to-severe HF and/or ischaemic heart disease (IHD).

Methods and Results: Results from two weight loss interventions at two centres, one in Denmark (DK - 12 week intervention in 21 subjects (14 LED, 7 controls)) and one in UK, (16 week intervention in 11 subjects (all LED, no controls) were
combined for a total of 32 subjects with HF or IHD and median BMI 36.2 kg/m2 (range 30-50). Weight loss was initiated with LED (800 kcal/day) followed by energy restricted and protein-rich diet (1200 kcal/day). Physical performance was
measured by six-minute walk test (DK) and maximum oxygen uptake (UK). The effect of treatment was analysed using linear mixed model. Weight loss in the intervention group: 13.9kg ± 6.5 and 1.21kg ± 1.8 in controls (P=0.000). Physical performance (the primary outcome) was improved by 17.8% ± 23.1 in the intervention group versus -22.1% ± 25.6 in the control group (P=0.000). Treatment also improved triglycerides (P=0.000), very low lipoprotein (P=0.001) and C-reactive protein (P=0.010).

Conclusion: Weight loss induced by LED in obese patients with moderate-to-severe HF or IHD resulted in clinically significant improvement in physical performance and cardiovascular risk markers.