Self-monitoring of Blood Pressure in Patients With Hypertension-Related Multi-morbidity: Systematic Review and Individual Patient Data Meta-analysis

BACKGROUND Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. This study examined whether self- monitoring can reduce clinic BP in patients with hyper tension-related co-morbidity. METHODS A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/ high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis. RESULTS A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with fol low-up data. Self-monitoring was associated with reduced clinic systollc BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (-3.12 mm Hg, [95% confidence intervals -4.78, -1.46 mm Hg]; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0,001 for ail outcomes), and possibly stroke (P < 0,004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease. CONCLUSIONS Self-monitoring lower BP regardless of the number of hypertensic related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.
This research was funded by the National Institute for Health Research School for Primary Care Research (NIHR SPCR number 267) and via an National Institute for Health Research Professorship (NIHR-RP-02-12-015). JS holds a Wellcome Trust/Royal Society Sir Henry Dale Fellowship (ref 211182/Z/18/Z). RM, KT and JS have, or previously received funding from the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care Oxford at Oxford Health NHS Foundation Trust. JM and RMcM are NIHR Senior Investigators. HB received funds from NHLBI (R01 HL070713). KM received funds from National Heart, Lung, and Blood Institute (NHLBI) (R01 HL090965). FDRH acknowledges part support from the NIHR School for Primary Care Research (SPCR), the NIHR Collaboration for Leadership in Applied Research in Health and Care (CLARHC) Oxford, and the NIHR Biomedical Research Centre (BRC), Oxford. RM has received research funding in terms of BP monitors from Omron. RM leads a programme of research around self-monitoring/management in stroke with BMc, funded by the Stroke Association and British Heart Foundation. BMc is the clinical lead for the Scottish Government's National programme for scaling up tele-monitoring in Scotland. HB receives research funds from Otsuka pharmaceuticals, Novo Nordisk, and Sanofi, but none of these studies are related to the current study. NH is now an employee of Bristol-Myers Squibb. The authors declare no other conflicts of interest. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.