Acupressure and hypnosis in arterial hypertension: a series of N-of-1 trials.

Background: Acupressure and hypnosis are used by patients with arterial hypertension despite limited evidence supporting their efficacy. The aim of this N-of-1 series was to evaluate feasibility, individual patient responses to both interventions, to inform personalized treatment decisions, and to assess overall effects of interventions. Methods: In a series of N-of-1 trials, we compared self-administered acupressure plus routine care (RC), hypnosis plus RC, and RC alone in patients with grade 1 or 2 hypertension. After a one-week run-in period with RC only, patients entered a six-week intervention phase consisting of two blocks with periods of acupressure, hypnosis and RC only, each followed by washout periods, administered in randomized order. Outcomes included systolic and diastolic blood pressure and pulse rate, which were measured by patients according to a standardized protocol. Patients recorded cardiovascular parameters, stress levels, vitality, and well-being using visual analogue scales, and documented feasibility and safety data in a study diary. The primary analysis of continuous outcomes was descriptive and conducted at the individual trial level. Secondary analyses included meta-analysis across all N-of-1 trials and outcomes. Overall group effects were analyzed using mixed-effects ANCOVA models. Results: Altogether 17 patients (59% female, mean age 54.4 [SD 7.6]) were included in this study. Feasibility of interventions was high, as reflected by an adherence rate exceeding 90%. Two patients showed reductions in systolic and diastolic blood pressure with both acupressure and hypnosis, and one patient with acupressure only, compared to RC. In the meta-analysis, no overall effects of acupressure or hypnosis on cardiovascular outcomes were observed. Overall, stress levels were higher during the run-in period (mean 43.6 [SD 18.9]) compared to the subsequent blocks and were similar between treatment periods. All other outcomes remained unchanged. Reported side effects were mild, rare, and occurred mainly during acupressure. Conclusion: This series of N-of-1 RCTs was feasible for self-administered acupressure and hypnosis for hypertension. No relevant changes in outcome parameters, including blood pressure, were observed at the group level, although selected patients showed individual changes. Further studies are needed to identify the treatment as well as individual conditions under which clinical benefits can be expected. Clinical trial registration: Deutsches Register für klinische Studien (DRKS) 00034937, https://drks.de/search/de/trial/DRKS00034937/details.