Evaluation of the Use of Home Blood Pressure Measurement Using Mobile Phone-Assisted Technology: The iVitality Proof-of-Principle Study.
BACKGROUND
Mobile phone-assisted technologies provide the opportunity to optimize the feasibility of long-term blood pressure (BP) monitoring at home, with the potential of large-scale data collection.


OBJECTIVE
In this proof-of-principle study, we evaluated the feasibility of home BP monitoring using mobile phone-assisted technology, by investigating (1) the association between study center and home BP measurements; (2) adherence to reminders on the mobile phone to perform home BP measurements; and (3) referrals, treatment consequences and BP reduction after a raised home BP was diagnosed.


METHODS
We used iVitality, a research platform that comprises a Website, a mobile phone-based app, and health sensors, to measure BP and several other health characteristics during a 6-month period. BP was measured twice at baseline at the study center. Home BP was measured on 4 days during the first week, and thereafter, at semimonthly or monthly intervals, for which participants received reminders on their mobile phone. In the monthly protocol, measurements were performed during 2 consecutive days. In the semimonthly protocol, BP was measured at 1 day.


RESULTS
We included 151 participants (mean age [standard deviation] 57.3 [5.3] years). BP measured at the study center was systematically higher when compared with home BP measurements (mean difference systolic BP [standard error] 8.72 [1.08] and diastolic BP 5.81 [0.68] mm Hg, respectively). Correlation of study center and home measurements of BP was high (R=0.72 for systolic BP and 0.72 for diastolic BP, both P<.001). Adherence was better in participants measuring semimonthly (71.4%) compared with participants performing monthly measurements (64.3%, P=.008). During the study, 41 (27.2%) participants were referred to their general practitioner because of a high BP. Referred participants had a decrease in their BP during follow-up (mean difference final and initial [standard error] -5.29 [1.92] for systolic BP and -2.93 [1.08] for diastolic BP, both P<.05).


CONCLUSIONS
Mobile phone-assisted technology is a reliable and promising method with good adherence to measure BP at home during a 6-month period. This provides a possibility for implementation in large-scale studies and can potentially contribute to BP reduction.
Leiden University Medical Center, Department of Gerontology & Geriatrics, Leiden, Netherlands.
Liselotte W
http://orcid.org/0000-0002-6438-5857
LW
Wijsman
Edo
http://orcid.org/0000-0002-7250-3390
E
Richard
Ricardo
http://orcid.org/0000-0002-5975-1058
R
Cachucho
Anton Jm
http://orcid.org/0000-0001-9314-123X
AJ
de Craen
Susan
http://orcid.org/0000-0002-7228-3690
S
Jongstra
Simon P
http://orcid.org/0000-0003-3106-3568
SP
Mooijaart
dementia; home-based measurements; hypertension; mobile phone