Long-term favorable cardiovascular risk profile and 39-year development of major and minor electrocardiographic abnormalities - The Chicago Healthy Aging Study (CHAS)

Background: Data are limited on long-term associations of favorable cardiovascular risk profile (i.e., low-risk) and changes in risk profile with ECG abnormality development.

Methods: The Chicago Healthy Aging Study (CHAS) involved re-examination of 1395 participants, ages 65-84 years in 2007-10, free of baseline major ECG abnormalities or MI in 1967-1973. Stratified sampling method was used to recruit participants based on their baseline risk profile (low-risk and not low-risk). Low-risk status was defined as untreated SBP/DBP ≤ 120/≤80 mm Hg, untreated total cholesterol <200 mg/dl, not smoking, BMI <25 kg/m², and no diabetes. ECG abnormalities were defined by Minnesota code criteria. Multinomial logistic regression was used.

Results: There were 28% women, 9% blacks, and 20% with baseline low-risk status. At follow-up, 21% developed ≥1 major ECG abnormalities, and 58% developed ≥1 minor ECG abnormalities. With multivariable adjustment, compared to those with 2 + high-risk factors, odds for developing from normal to any major ECG abnormalities were lower by 57%, 49%, and 35%, respectively, in persons with low-risk, any moderate-risk, and 1 high-risk factor (P-trend = 0.002). Findings were similar for some common specific subtypes of major and minor abnormalities. Associations were mainly due to baseline smoking and BMI. Remaining free of high-risk factors, or improving risk profile over time was also associated with lower major ECG abnormality development by 70% vs. always having any high-risk factor.

Conclusions: Favorable CVD risk profile earlier in life and maintenance or improvement in risk profile over time are associated with lower risk of ECG abnormality development at older age.