Wataru Umishio

Mortality due to cardiovascular disease rises sharply in winter. Known as excess winter mortality, this phenomenon is partially explained by cold exposure-induced high blood pressure. Home blood pressure, especially in the morning, is closely associated with cardiovascular disease risk. We conducted the first large nationwide survey on home blood pressure and indoor temperature in 3775 participants (2095 households) who intended to conduct insulation retrofitting and were recruited by constructi

The coronavirus disease 2019 (COVID-19) pandemic has drastically changed work styles and environments. Given the coexistence of work in the office and work from home (WFH) in the future, studies are needed to identify ways to increase productivity when working in both places. We conducted a questionnaire survey and environment measurements of 916 workers in 22 offices across 2 weeks in November-December 2020 in Japan. While average workdays at the offices decreased from 4.9 to 3.9 days/week, tho

The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter

Home blood pressure (HBP) variability is an important factor for cardiovascular events. While several studies have examined the effects of individual attributes and lifestyle factors on reducing HBP variability, the effects of living environment remain unknown. We hypothesized that a stable home thermal environment contributes to reducing HBP variability. We conducted an epidemiological survey on HBP and indoor temperature in 3785 participants (2162 households) planning to have their houses retr

Insulation retrofitting significantly reduced HBP and was more beneficial for reducing the morning HSBP of hypertensive patients.

Current countermeasures for preventing hypertension emphasize only improvements to lifestyle. Recently, improving life environment has attracted attention, in parallel with publication of the WHO Housing and health guidelines. We quantitatively evaluated the relationship between housing thermal environment and blood pressure (BP) in a real-world setting. We conducted a nationwide, prospective intervention study-the Smart Wellness Housing survey-in Japan, as a non-randomized controlled trial. The

The trial was retrospectively registered on 27 Dec 2017 to the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR, https://www.umin.ac.jp/ctr/ , registration identifier number UMIN000030601 ).

Besides lifestyle modification, improving indoor thermal environment through strategies such as installing high thermal insulation and appropriate use of heating devices may contribute to better serum cholesterol condition.

Residents themselves are responsible for controlling their living environment, and their perception of coldness is important to protect their health. Although previous studies examined the association between perceived coldness and indoor temperature, they did not consider the spatial-temporal differences in indoor temperatures. This study, conducted in Japan, measured indoor temperatures in 1,553 houses across several rooms (living room, changing room, and bedroom) and heights (at 1 m above the

A cardiac disease is the second most common cause of death and a cerebrovascular disease is the fourth, a major cause of which is hypertension. Hypertension is an asymptomatic disease, which is called “silent killer”, affecting one-third of the population. Therefore, it is essential not only “high risk approaches” which are measures for hypertensive individuals such as treatment with an antihypertensive drug but also “population approaches” which are measures to reduce blood pressure (BP) of ent

Upgrading insulation and residing in warmer homes could be cost-effective strategies. When conducting insulation retrofitting, lower-cost methods such as partial insulation retrofitting should be considered. These findings support decision-making for residents and policymakers.

This study aimed to clarify the compositional and contextual effects of indoor temperature on blood pressure (BP). These effects are respectively defined as the increase in BP per 1°C decrease in indoor temperature on a particular day and the increase in BP per 1°C decrease in average indoor temperature of houses based on a multilevel model. Measurement data were collected through field surveys in winter (2012-2014). Both effects were significant, and the sum of the effects was 0.57 mmHg/°C for

In Japan, the total financial loss caused by sleep disorders is estimated to be about 3.5 trillion yen annually. Chronic sleep disorders are a factor in lifestyle-related diseases and can affect life expectancy. The Japanese government has set guidelines for improving sleep-related problems (e.g., Healthy Japan 21). However, the goal for improvement of sleep-related problems, —a reduction from 18.4% in 2009 to 15.0% in 2022 in the percentage of people who do not receive adequate rest from sleep—

Japan is confronted with the problems of an aging population, and government finances are severely strained by rising expenditures on medical and nursing care. It is expected that medical and nursing care expenses reached 45 trillion yen in 2010, and such expenses are expected to double to 92 trillion yen by 2025. An effective measure for lowering such expenditures is the prevention of cardiovascular disease, a major cause of which is hypertension. Recently, the effects of the indoor thermal env