Feasibility study to assess the delivery of a novel isometric exercise intervention for people with high blood pressure in a healthcare setting

BACKGROUND: Hypertension affects 1:4 adults and increases the risk of CV disease. Management aims to reduce blood pressure to a level that minimizes risk; up to 50% of people don't achieve blood pressure targets often due to insufficient treatment or poor adherence. Exercise has a role to play in the management of hypertension. The impact of isometric exercise on hypertension in healthcare settings is poorly understood. METHODS: Randomized controlled open-label multicentre feasibility study of isometric exercise compared to standard care in unmedicated hypertensives. Participants received an individualised isometric wall squat prescription and performed 4 x 2-minute bouts thrice weekly for 6-months. We assessed recruitment, deliverability, attrition, adherence, and variance in blood pressure change. RESULTS: 41 participants (56 +/- 15 years), 59% women, were randomized. Isometric exercise was found to be easily deliverable to all participants. At 6-months 34% withdrew, of those who completed isometric exercise 87% of their sessions were at the correct intensity. Variance in blood pressure change was 14.4 mmHg. The study was not powered to show a difference in blood pressure between groups, however blood pressure reductions were seen in the intervention group at all study time points compared to baseline. CONCLUSIONS: The results have allowed us to calculate a sample size (n=542) for a full randomised controlled trial. The results demonstrate good acceptability and adherence rates to the treatment protocol. Our results show a signal towards a consistent systolic blood pressure reduction in the isometric exercise group compared to baseline. REGISTRATION: [NCT04936022][1] https://classic.clinicaltrials.gov/ct2/show/NCT04936022cond=isometric+exercise&draw=2&rank=7 Registry Identifier: ISRCTN:13472393 ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial Trial number: [NCT04936022][1] https://classic.clinicaltrials.gov/ct2/show/[NCT04936022][1]?cond=isometric+exercise&draw=2&rank=7 Registry Identifier: ISRCTN 13472393 ### Clinical Protocols ### Funding Statement This study was funded by the National Institute for Health and Care Research (NIHR), grant number NIHR200485 ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: IRAS ID: 274676 London- Bromley Research Ethics Committee I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Anonymised data from the study can be provided on request [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT04936022&atom=%2Fmedrxiv%2Fearly%2F2024%2F02%2F18%2F2024.02.16.24302961.atom