Cardiac structure and function and insulin resistance in morbidly obese patients: does superobesity play an additional role?

OBJECTIVE: To evaluate the impact of superobesity, defined as body mass index (BMI) ≥50, on cardiac structure and function. METHODS: Using echocardiography, we studied 198 asymptomatic patients (mean age 48 ± 13 years, 29.3% were men) with a BMI ≥40. Insulin resistance was measured using the Homeostasis Model Assessment of insulin resistance (HOMA-IR). Patients were divided into 2 groups: morbidly obese (BMI ≥40 and <50; n = 160) and superobese (BMI ≥50; n = 38). RESULTS: There were no significant differences in age, gender, hypertension and diabetes between groups. Superobese patients had higher LV mass (66.0 ± 14.7 vs. 59.9 ± 11.9 g/m(2.7), p = 0.007), left ventricular (LV) end-diastolic (33.8 ± 7.7 vs. 31.5 ± 7.1 ml/m(2.7), p = 0.041) and end-systolic (12.2 ± 3.6 vs. 10.9 ± 2.8 ml/m(2.7), p = 0.016) volumes, left atrial volume (13.8 ± 4.5 vs. 12.2 ± 3.9 ml/m(2.7), p = 0.029), peak velocity of transmitral flow in early diastole/early diastolic peak myocardial velocity ratio (9.1 ± 2.6 vs. 8.2 ± 2.2, p = 0.03) and HOMA-IR (9.7 ± 7.3 vs. 7.3 ± 6.5, p = 0.047). LV ejection fraction was similar. CONCLUSIONS: Superobesity is associated with insulin resistance and a worse impact on cardiac remodeling and LV diastolic function than morbid obesity. Prospective studies are needed to evaluate whether such further classification of morbid obesity could stratify the cardiovascular risk in these patients more accurately.

Impact of metabolic syndrome traits on cardiovascular function: should the Adult Treatment Panel III definition be further stratified?

AIMS: The aims of the study were to evaluate whether a further classification of metabolic syndrome according to the number of traits (based on the Adult Treatment Panel III definition) could better explain the impact on cardiovascular remodeling and function, and to assess the role of single metabolic syndrome components in this regard. METHODS: We studied by echocardiography and carotid ultrasound 435 asymptomatic patients with metabolic syndrome. Patients with coronary artery disease or more than mild valvular heart disease were excluded. Carotid stiffness index (ß) was measured using a high-resolution echo-tracking system. Patients with metabolic syndrome were divided into two groups: metabolic syndrome with three traits (Gr.1) and metabolic syndrome with four or five traits (Gr. 2). RESULTS: Patients in Gr. 2 had higher left ventricular mass index (P < 0.001), left ventricular end-diastolic volume index (P = 0.029), left atrial volume index (P = 0.002), E/e' ratio (P = 0.002), intima-media thickness (P = 0.031), and prevalence of plaques (P = 0.01) than patients in Gr. 1. Left ventricular ejection fraction was similar in both groups. The mean carotid ß index tended to be higher in Gr. 2. Considering metabolic syndrome traits separately, in an age-corrected multivariate analysis, abdominal obesity was found to have the strongest association with cardiac structure and carotid artery atherosclerosis and stiffness. CONCLUSION: An increasing number of metabolic syndrome traits had a significantly worse impact on cardiac remodeling and function and carotid artery atherosclerosis. Abdominal obesity showed the strongest association with cardiac structure, carotid artery stiffness, and intima-media thickness. Prospective studies are needed to evaluate whether a new classification of metabolic syndrome using the number of traits could add prognostic information.