Development of the metabolic syndrome and electrocardiographic features of left ventricular hypertrophy in middle-aged working subjects.

Background and aims. The metabolic syndrome (MS) leads to excess cardiovascular disease, including heart failure. Left ventricular hypertrophy (LVH) is common in MS patients, but it is unknown whether onsets of the MS and LVH coincide. Herein, we tested the association between development of the MS and of electrocardiographic LVH in a cohort of middle-aged individuals. Methods. We included 303 working subjects (mean age 43.0±6.2; 41% males), followed-up for 4.3±0.8 years. ATP-III MS components were determined. Electrocardiographic LVH features were assessed by the Sokolow and Cornell voltage indexes and the Rohmilt-Estes score. Results. At baseline, the Cornell index was significantly higher in subjects with (n=55; 18.2%) than in those without MS (12.8±6.4 vs 10.9±5.4 mm; p=0.023), while the Sokolow index and Rohmilt- Estes score were not different. At follow-up, individuals who developed (n=51) compared to those who did not develop MS showed a significant increase in Cornell voltage index (1.0±0.6 vs - 0.55±0.3 mm; p=0.035) and in Rohmilt-Estes score (0.17±0.17 vs -0.08±0.04; p=0.028). The change in Cornell index over time was directly correlated with change in the number of MS components (r=0.133; p=0.02) and HOMA-IR (r=0.117; p=0.046). The association between MS onset and increase in Cornell index / Rohmilt-Estes score was independent from confounders. Conclusions. In a young population of working subjects, the development of MS is associated with worsening features of LVH. Early LVH electrocardiographic screening in young subjects who develop the MS should be considered and performed using the Cornell voltage index