# Urgent Notification Intervention of Home Blood Pressure in Cohort Studies of the Tohoku Medical Megabank Project

## TL;DR

A system was developed to urgently notify participants of dangerously high home blood pressure readings in a large health study.

## Contribution

A novel urgent notification system for critical home blood pressure readings was implemented and evaluated in a large cohort study.

## Key findings

- Approximately 1.2% of participants had critical home blood pressure readings requiring urgent notification.
- Abnormalities in blood sugar, renal function, and lipid levels often occurred alongside high blood pressure.
- About 60% of notified participants sought medical care after receiving urgent notifications.

## Abstract

The Tohoku Medical Megabank (TMM) was established for creative reconstruction from the Great East Japan Earthquake and tsunami in 2011. Two prospective genome cohort studies in Miyagi prefecture have successfully recruited approximately 127,000 participants. The health status of these individuals was evaluated at the initial recruitment, and follow-up health checkups have been conducted every 5 years. During these health checkups, unexpected critical values were encountered, which prompted us to develop an urgent notification system.

We analyzed the frequency of critical values observed in home blood pressure (HBP) test in an urgent notification office (UNO). We returned the critical values by urgent notification before the notifications of regular results. In addition, the impact of the TMM urgent notification on the participants was evaluated.

We issued urgent notifications of the critical values of extremely high HBP. Of the 21,061 participants who underwent HBP measurements, 256 (1.2%) met the criteria for urgent notification. It was found that abnormalities in blood sugar levels, renal function, and lipid values were frequently concurrent with the abnormal HBP readings. Annual questionnaires administered after the urgent notification, approximately 60% of those went to hospitals or clinics.

The urgent notification system for hypertensive emergency with HBP in the TMM was well accepted by the participants and encouraged them to seek medical care. The system has been useful in addressing the prolonged healthcare problems and in promoting health care in large-scale disaster damaged areas.