Background: Much attention has been focused on the primary prevention of ischemic heart disease (IHD), but the prevalence and prognostic indicators of IHD remain unclear in healthy Japanese subjects.
Hypothesis: The purpose of this study was to determine the predictors for the transition of IHD in healthy adult subjects using data from annual medical examinations.
Methods: We analyzed clinical data on 2710 healthy subjects (1836 men and 874 women aged 26-76 years in 2000) who underwent medical examinations in both 2000 and 2002. Ischemic changes in the electrocardiogram (ECG) suggestive of IHD were defined as the existence of abnormal Q-wave and/or ST-T abnormalities without left ventricular high voltage. We assigned the subjects to two groups: the ischemic heart group (Group I), including subjects with normal ECG findings in 2000, followed by suspicious ischemic changes in the ECGs in 2002; and the normal group (Group N), including subjects with normal ECGs in both 2000 and 2002.
Results: Fifty-nine subjects (2%, 20 women) were assigned to Group I and 2,538 subjects (96%, 810 women) were assigned to Group N. There were significant differences between the two groups in baseline age (Group I vs. Group N: 53 vs. 47 years, p < 0.001), body mass index (24 vs. 23 kg/m2, p = 0.036), systolic blood pressure (132 vs. 122 mmHg, p < 0.001), diastolic blood pressure (83 vs. 76 mmHg, p < 0.001), and fasting plasma glucose (109 vs. 96 mg/dl, p < 0.001). Fasting plasma glucose significantly increased in Group I (from 109 to 113 mg/dl, p = 0.034) during the study. Multivariate analysis showed significant differences in age (p < 0.001) and fasting plasma glucose (p = 0.0053).
Conclusion: Advanced age and relatively elevated fasting plasma glucose appeared to be significant predictors of ECG findings suggestive of IHD in normal subjects in the short period of 2 years.