We aimed at investigating the prevalence and the prognostic significance for fatal and non fatal cardiovascular (CV) events of different electrocardiographic (ECG) criteria for left ventricular hypertrophy (LVH) in normal weight, overweight and obese subjects in an adult Italian population.Design and method:
18330 adults (mean age 54 ± 11 years, 55% women, 53% hypertensives) were analyzed from the Moli-sani cohort. Obesity was defined using the ATPIII criteria. ECG-LVH was defined according to ESH-ESC guidelines.Results:
The age and sex-adjusted prevalence of ECG-LVH did not differ from normal weight subjects to class 2–3 obesity subjects when the strain or Cornell Voltage (CorVol) criteria were used. In overweight and obese patients, as compared with normal weight subjects, a progressively lower prevalence of ECG-LVH was observed when the Sokolow-Lyon (SL) index was used, while a higher prevalence was shown by using the aVL-R-wave voltage (>11 and >5.7 mm) and the Cornell Voltage-QRS duration product (CP). The incidence of CV events was significantly greater in subjects with ECG-LVH diagnosis by the CorVol (HR 1.89, 95% CI 1.05 to 3.39), the CP (HR 1.87, 95% C1.31 to 2.67), and the presence of strain (HR 1.89, 95% CI 1.05 to 3.39). After adjusting for different confounders (age, sex, cigarette, hypertension, hypercholesterolemia, diabetes, income, education, occupational class, physical activity) and for BMI categories, only the CP remained significantly associated to a higher incidence of CV events (HR 4.8; 95% CI 1.85 to 12.45). The predictive significance of different LVH criteria were assessed across BMI categories; after adjusting for different confounders, LVH identified by a R wave in aVL > 11 (HR 4.63; 95% CI 1.37 to 15.62) and the presence of strain (HR 24.1; 95% CI 2.85 to 204) were significantly associated with an increased risk of CV events in class 2–3 obesity subjects; CV-LVH remained an independent predictor of events only in class 1 obesity individuals (HR 1.76; 95% CI 1.16 to 2.67), while CP-LVH predicted an increased risk of CV events only in normal weight or overweight subjects (HR 2.55; 95% CI 1.53 to 4.26 and HR 2.72; 95% CI 1.14 to 6.48, respectively).Conclusions:
Our results confirm that ECG-LVH prevalence may differ according to the criteria used, across BMI categories. The use of different LVH criteria according to BMI categories may improve CV risk stratification in a general population independently of several confounding factors.