Racial Disparities in Pre-clinical Cardiac Abnormality and its Associations with Diabetes Mellitus and Renal Insufficiency: Translation of Research into Policy

Background: Early detecting pre-clinical cardiac abnormality provides a crucial opportunity to reduce the burden of cardiovascular disease (CVD). Objectives: To examine prevalence of pre-clinical cardiac abnormality and its risk factors among Whites, African Americans (AA) and Mexican Americans (MA). Methods: The study used data from the third National Health and Nutrition Examination Survey. In the survey, electrocardiogram (ECG) interval data were collected on 8561 participants aged>=40. We used Minnesota code criteria of major ECG abnormality to define pre-clinical abnormality. Diabetes mellitus (DM) was defined using the WHO (1985) criteria, and renal insufficiency was defined according to glomerular filtration rate. Results: Prevalence of subjects with self-report physician-diagnosed coronary heart disease was 12.8% in men and 9.3 in women. However prevalence of subjects who had no history of CVD but had major ECG abnormality (i.e., pre-clinical cardiac abnormality) were 13%, 17% and 13.7% among whites, AA and MA men respectively (p<0.001). These corresponding values were 8.6%, 10.8% and 9.7% in women. AA and MA had significantly higher prevalence of DM, hypertension and renal insufficiency than Whites. Furthermore, subjects with a history of DM, hypertension and renal insufficiency had significantly higher risk of having major ECG abnormality. Logistic regression analysis indicates that risk of pre-clinical cardiac abnormality was significantly associated with age, race, education levels, diabetes and renal insufficiency. Conclusion: AA and MA have higher prevalence of pre-clinical cardiac abnormality. Great efforts should be made to diagnose this disease at early stage and prevent DM, hypertension and renal insufficiency.