Does self-monitoring reduce blood pressure? Meta-analysis with meta-regression of randomized controlled trials

Abstract

Introduction. Self-monitoring of blood pressure (BP) is an increasingly common part of hypertension management. The objectives of this systematic review were to evaluate the systolic and diastolic BP reduction, and achievement of target BP, associated with self-monitoring.

Methods. MEDLINE, Embase, Cochrane database of systematic reviews, database of abstracts of clinical effectiveness, the health technology assessment database, the NHS economic evaluation database, and the TRIP database were searched for studies where the intervention included self-monitoring of BP and the outcome was change in office/ambulatory BP or proportion with controlled BP. Two reviewers independently extracted data. Meta-analysis using a random effects model was combined with meta-regression to investigate heterogeneity in effect sizes.

Results. A total of 25 eligible randomized controlled trials (RCTs) (27 comparisons) were identified. Office systolic BP (20 RCTs, 21 comparisons, 5,898 patients) and diastolic BP (23 RCTs, 25 comparisons, 6,038 patients) were significantly reduced in those who self-monitored compared to usual care (weighted mean difference (WMD) systolic −3.82 mmHg (95% confidence interval −5.61 to −2.03), diastolic −1.45 mmHg (−1.95 to −0.94)). Self-monitoring increased the chance of meeting office BP targets (12 RCTs, 13 comparisons, 2,260 patients, relative risk = 1.09 (1.02 to 1.16)). There was significant heterogeneity between studies for all three comparisons, which could be partially accounted for by the use of additional co-interventions.

Conclusion. Self-monitoring reduces blood pressure by a small but significant amount. Meta-regression could only account for part of the observed heterogeneity.

Key words::

• Blood pressure monitoring
• hypertension
• meta-analysis
• self-monitoring

Acknowledgements

EB, RM, and JM performed the searches and extracted the data. EB, RM, and RH performed the analyses. All authors participated in the writing of the final document and approved the final version. RM will act as guarantor for the study.

We would like to thank the following authors and their teams for sending us requested data to aid with the analyses: BM Mehos, A Baque, AJ Zillich.

Declaration of interest: This work was funded by a National Institute of Health Research (NIHR) Programme grant. The views expressed in this report are those of the authors and not necessarily those of the NIHR. RM is funded by an NIHR Career Development Fellowship. Birmingham and Cambridge were founder members of the National School for Primary Care Research. The authors declare that they have no competing interests regarding this paper.