Overweight and obesity impair left ventricular systolic function as measured by left ventricular ejection fraction and global longitudinal strain.

Aims: Obesity is associated with type 2 diabetes mellitus, left ventricular diastolic dysfunction and heart failure but it is unclear to which extent it is related to left ventricular systolic dysfunction. The aim of the study was to explore the effects of overweight and obesity on left ventricular systolic function in patients with type 2 diabetes mellitus and a control group of non-diabetic persons.

Methods: We prospectively investigated 384 patients with type 2 diabetes mellitus, and 184 controls who participated in the CARDIPP and CAREFUL studies. The participants were grouped according to body mass index (normal weight < 25 kg/m, overweight 25-29 kg/m, and obesity ≥ 30 kg/m). Echocardiography was performed at the beginning of the study and after 4-years in the patient group.

Results: Univariable and multivariable regression analysis revealed that variations in left ventricular ejection fraction, global longitudinal strain, left ventricular mass and diastolic function expressed as E/é (the ratio between early diastolic mitral flow and annular motion velocities) all are related to body mass index. The mean and standard deviation of left ventricular ejection fraction and global longitudinal strain values were 57% (8%) vs. - 18.6% (2.3%) for normal weight patients, 53% (8%) vs. - 17.5% (2.3%) for overweight, and 49% (9%) vs. - 16.2% (3.0%) for obese (p < 0.05 vs. p < 0.05). Corresponding results in the control group were 58% (6%) vs. - 22.3% (3.0%), 55% (7%) vs. - 20.8% (3.1%) and 54% (8%) - 19.6% (4.0%) (p < 0.05 vs. p < 0.05). Patients who gained weight from baseline to follow-up changed left ventricular ejection fraction (median and interquartile range) by - 1.0 (9.0) % (n = 187) and patients who lost weight changed left ventricular ejection fraction by 1.0 (10.0) % (n = 179) (p < 0.05).

Conclusion: Overweight and obesity impair left ventricular ejection fraction and global longitudinal strain in both patients with type 2 diabetes mellitus and non-diabetic persons. Trial registration ClinicalTrials.gov identifier NCT 01049737.