What were the findings of the two studies included in the review?
The first study included 38 people with HFREF or HFPEF on optimally tolerated medical therapy with normal serum sodium. It compared a moderate salt intake (2300mg/day sodium) with a low salt intake (1500mg/day sodium). The outcome QoL (as measured by the KCCQ) showed a clinically important reduction in quality of life with the low sodium diet. The low sodium diet also showed no clinical effect on renal function. The second study included 25 people, who were already enrolled in a trial of an intrathoracic impedance monitoring device and who had been hospitalised within the previous 6 months. It compared an education programme providing support to maintain fluid restriction at 1.5-2L (intervention) with general support unrelated to the fluid restriction (control). The outcome QoL (as measured by the EQ5D VAS) showed a clinically important reduction in quality of life with the fluid restriction programme. The fluid restriction programme had no clinical effect on the outcome oedema. 