OUTSTEP-HF: randomised controlled trial comparing short-term effects of sacubitril/valsartan versus enalapril on daily physical activity in patients with chronic heart failure with reduced ejection fraction

Aims: OUTSTEP-HF compared the effect of sacubitril/valsartan vs. enalapril on 6-min walk test (6MWT) distance, non-sedentary daytime physical activity and heart failure (HF) symptoms in patients with HF with reduced ejection fraction (HFrEF).

Methods and results: Ambulatory patients (n = 621) with stable symptomatic HFrEF were randomised 1:1 to sacubitril/valsartan (n = 310) or enalapril (n = 311). Changes in physical activity and mean daily non-sedentary daytime activity from baseline to Week 12 were measured using 6MWT and a wrist-worn accelerometer device, respectively. After 12 weeks, 6MWT improved by 35.09 m with sacubitril/valsartan [97.5% confidence interval (CI) 27.85, 42.32] and by 26.11 m with enalapril (97.5% CI 18.78, 33.43); however, there was no significant difference between groups [least squares means treatment difference: 8.98 m (97.5% CI -1.31, 19.27); P = 0.0503]. Mean daily non-sedentary daytime activity decreased by 27 min with sacubitril/valsartan and by 21 min with enalapril [least squares means treatment difference: -6 min (97.5% CI -25.7, 13.4), P = 0.4769] after 12 weeks. 6MWT improved by ≥30 m in 51% of patients in the sacubitril/valsartan group vs. 44% of patients treated with enalapril (odds ratio 1.251, 95% CI 0.895, 1.748). At Week 4, non-sedentary daytime activity increased by ≥10% in 58% of patients treated with sacubitril/valsartan vs. 64% with enalapril; 58% of patients treated with sacubitril/valsartan reported improved HF symptoms as assessed by patient global assessment vs. 43% with enalapril. However, these differences did not persist at Week 12.

Conclusion: After 12 weeks of treatment, there was no significant benefit of sacubitril/valsartan on either 6MWT or daytime physical activity measured by actigraphy compared with enalapril.