Prospective external validation of the Predicting Out-of-OFfice Blood Pressure (PROOF-BP) strategy for triaging ambulatory monitoring in the diagnosis and management of hypertension: observational cohort study

Sheppard, James P; Martin, Una; Gill, Paramjit; Stevens, Richard; Hobbs, FD Richard; Mant, Jonathan; Godwin, Marshall; Hanley, Janet; McKinstry, Brian; Myers, Martin; Nunan, David; McManus, Richard J

Abstract

Objectives: Triaging patients with suspected high blood pressure for ambulatory blood pressure monitoring (ABPM), on the basis of their clinic blood pressure and characteristics, may reduce the need for ABPM. This study aimed to prospectively validate this new approach using data from routine practice.
Design: Prospective observational cohort study.
Setting: Ten primary care practices and one hospital in the UK.
Participants: Consecutive patients aged >18 years referred for ABPM in routine practice.
Interventions: All patients underwent ABPM and had the new triage algorithm (PROOF-BP) applied.
Main outcome measures: Proportion correctly classified with hypertension using the triaging strategy compared to the reference standard of daytime ABPM. Sensitivity, specificity and area under the receiver operator characteristic curve (AUROC) for detecting hypertension.
Results: A total of 887 patients (mean age 52.8±16.2 years) were referred for ABPM and enrolled during the study period. The triaging strategy correctly classified hypertensive status in 801 patients (90%, 95% CI 88% to 92%) and had a sensitivity of 97% (95% CI 96% to 99%) and specificity of 76% (95% CI 71% to 81%) for hypertension. The AUROC was 0.86 (95% CI 0.84 to 0.89). Use of triaging, rather than uniform referral for ABPM in routine practice would have resulted in 435 patients (49%, 95% CI 46% to 52%) being referred for ABPM and the remainder managed on the basis of their clinic measurements. Of these, 69 (8%, 95% CI 6% to 10%) would have received treatment that would have been deemed unnecessary had they received ABPM.
Conclusions: In a population of patients referred for ABPM, this new triaging approach accurately classified hypertensive status for most, with half the utilisation of ABPM compared with usual care. This triaging strategy can therefore be recommended for diagnosis or management of hypertension in patients where ABPM is being considered, particularly in settings where resources may be limited.

Citation

Sheppard, J. P., Martin, U., Gill, P., Stevens, R., Hobbs, F. R., Mant, J., Godwin, M., Hanley, J., McKinstry, B., Myers, M., Nunan, D., & McManus, R. J. (2018). Prospective external validation of the Predicting Out-of-OFfice Blood Pressure (PROOF-BP) strategy for triaging ambulatory monitoring in the diagnosis and management of hypertension: observational cohort study. The BMJ, 361, k2478. https://doi.org/10.1136/bmj.k2478

• Journal Article Type: Article
• Acceptance Date: May 7, 2018
• Publication Date: Jun 27, 2018
• Deposit Date: May 24, 2018
• Publicly Available Date: Jul 24, 2019
• Journal: BMJ
• Print ISSN: 0959-8138
• Electronic ISSN: 1756-1833
• Peer Reviewed: Peer Reviewed
• Volume: 361
• Pages: k2478
• DOI: https://doi.org/10.1136/bmj.k2478
• Keywords: blood pressure monitoring, prediction modelling, primary prevention, cardiovascular disease, diagnostic accuracy
• Public URL: http://researchrepository.napier.ac.uk/Output/1178664
• Contract Date: May 24, 2018