Prognosis of patients with apparent treatment-resistant hypertension-a feasibility study

Peter Hayes; Hannah Kielty; Monica Casey; Liam G Glynn; Gerard J Molloy; Hannah Durand; John Newell; Andrew W Murphy

doi:10.1186/s40814-018-0232-5

Prognosis of patients with apparent treatment-resistant hypertension-a feasibility study

Pilot Feasibility Stud. 2018 Jan 30:4:43. doi: 10.1186/s40814-018-0232-5. eCollection 2018.

Authors

Peter Hayes¹, Hannah Kielty², Monica Casey¹, Liam G Glynn³, Gerard J Molloy⁴, Hannah Durand⁴, John Newell⁵, Andrew W Murphy^{1

6}

Affiliations

¹ 1Discipline of General Practice, School of Medicine, National University of Ireland, Galway, Ireland.
² 2School of Medicine, NUI Galway, Galway, Ireland.
³ 3Graduate Entry Medical School, University of Limerick, Limerick, Ireland.
⁴ 4School of Psychology, NUI Galway, Galway, Ireland.
⁵ 5School of Mathematics, Statistics and Applied Mathematics, NUI Galway, Galway, Ireland.
⁶ Health Research Board Primary Care Clinical Trials Network, Galway, Ireland.

Abstract

Background: Most cases of hypertension can be effectively treated with lifestyle changes together with medications, but within this population lies a group with more difficult to treat hypertension-those with apparent treatment-resistant hypertension (aTRH). The American Heart Association and the UK National Institute for Health and Care Excellence have both highlighted the need for further research into the prognosis of patients with resistant hypertension, both apparent and true.

Methods: In 16 practices affiliated to a university research network, 646 patients had been identified with apparent treatment-resistant hypertension. To inform a planned full cohort study of these patients, we conducted a feasibility study within three practices to determine participation of practices and patients, availability of outcome measures and data collection times.

Results: All three practices fully participated and 205/210 (98%) patients were followed up for a median of 23 months. Thirty-five outcome events of interest occurred-the most common was the new onset of retinopathy (9 cases). Eight percent (17/210) had the main composite outcome of death or serious incident cardiovascular event. Of the six patients who died, identification of cause of death was possible from practice records in five; the national General Register Office was successfully used for the final patient. There were 123 admissions, both day and overnight, recorded in 94 individual patients. Average manual systolic blood pressure measurements improved from baseline by 5 mmHg to 138 (SD 19) mmHg; diastolic remained the same at 75 (SD 12) mmHg. Average eGFR increased from 58.8 (SD17.4) to 66 (SD19.7) mls/min/1.73m². The average time for data collection per patient was 12 mins.

Conclusions: This study demonstrates that the proposed methodology for a full cohort study within general practice of patients with apparent treatment hypertension is both acceptable to practices and feasible. An adequately powered subsequent follow-up study of the entire cohort appears possible.

Keywords: Feasibility; Hypertension; Primary care; Prognosis; Treatment resistant hypertension.