Changes in ischaemic ECG abnormalities and subsequent risk of cardiovascular disease.
OBJECTIVE
The prognostic importance of changes in ischaemic ECG abnormalities over time (especially ST-T abnormalities) among Asians has not been fully investigated. We examined the associations between changes in ischaemic abnormalities upon serial ECG (improvement, persistence, deterioration) and cardiovascular disease (CVD) risk.


METHODS
A prospective study cohort was conducted with 9374 men and women aged 40-69 years in four communities. Participants had multiple ECGs at study entry and during the next 10 years, and were followed up for a median period of 23.0 years. Total CVD (stroke and coronary heart disease) was ascertained under systematic surveillance. ECG abnormalities were defined by the Minnesota Code, ST depression (Code4), abnormal T wave (Code5) and categorised into nine groups (no-no, no-minor, no-major, minor-no, minor-minor, minor-major, major-no, major-minor, major-major) by comparison with the point of entrance and maximum change.


RESULTS
We documented 1196 CVD events. Compared with no-no abnormality, no-minor, minor-major and major-major in Code4, HRs (95% CI) adjusted for cardiovascular risk factors were 1.19 (1.00-1.42), 1.57 (1.15-2.12) and 1.87 (1.42-2.47). Similar results were observed in Code5.


CONCLUSIONS
Changes in ischaemic ECG abnormalities from none to minor, and minor to major, as well as persistent major abnormalities, were associated with an increased risk of CVD.
Public Health, Department of Social Medicine , Osaka University Graduate School of Medicine , Osaka , Japan.
Takeshi
T
Sawai
Public Health, Department of Social Medicine , Osaka University Graduate School of Medicine , Osaka , Japan.
Hironori
H
Imano
Osaka Center for Cancer and Cardiovascular Disease Prevention , Osaka , Japan.
Isao
I
Muraki
Osaka Center for Cancer and Cardiovascular Disease Prevention , Osaka , Japan.
Mina
M
Hayama-Terada
Osaka Center for Cancer and Cardiovascular Disease Prevention , Osaka , Japan.
Yuji
Y
Shimizu
Public Health, Department of Social Medicine , Osaka University Graduate School of Medicine , Osaka , Japan.
Renzhe
R
Cui
Public Health, Department of Social Medicine, Osaka University Graduate School of Medicine, Osaka, Japan; Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
Akihiko
A
Kitamura
Osaka Center for Cancer and Cardiovascular Disease Prevention , Osaka , Japan.
Masahiko
M
Kiyama
Osaka Center for Cancer and Cardiovascular Disease Prevention , Osaka , Japan.
Takeo
T
Okada
Department of Epidemiology , Fukushima Medical University School of Medicine , Fukushima , Japan.
Tetsuya
T
Ohira
Department of Public Health Medicine, Faculty of Medicine , University of Tsukuba , Ibaraki , Japan.
Kazumasa
K
Yamagishi
Department of Public Health, Dokkyo Medical University School of Medicine , Tochigi , Japan.
Mitsumasa
M
Umesawa
Department of Community Health, Faculty of Medicine , University of Tsukuba , Ibaraki , Japan.
Tomoko
T
Sankai
Public Health, Department of Social Medicine , Osaka University Graduate School of Medicine , Osaka , Japan.
Hiroyasu
H
Iso