Type I Diabetes Mellitus (T1DM) is one of the most common endocrine diseases in the world. It is also the dominant type of diabetes mellitus among children and adolescents that, if left uncontrolled, becomes a major risk factor for cardiovascular disorders and may cause clinical and subclinical cardiac dysfunction.
This study aimed to compare uncontrolled pediatric and adolescent patients and similar healthy people regarding cardiac function according to echocardiography and B-type Natriuretic Peptide (BNP).
This case-control study was carried out in the Outpatient Department of Nemazi tertiary hospital in Shiraz, Iran between June and September 2016. The study included 29 consecutive outpatient cases aged 5 - 18 years who had been diagnosed with T1DM for more than three years and had normal ejection fraction in M-mode echocardiography. The control group consisted of 29 age- and gender-matched healthy non-diabetic volunteers. Both cases and controls were selected by simple random sampling. The participants underwent clinical evaluation, including BNP assay and echocardiographic examination composed of two-dimensional echocardiography, M-mode echocardiography, pulsed Doppler imaging, and Tissue Doppler Imaging (TDI). P-value ≤ 0.05 was considered to be statistically significant.
The results revealed a decline in cardiac function in TDI, which was related to the HbA1C level and duration of the disease. A significant difference was found between the cases and the controls regarding the left ventricular posterior wall, interventricular septal diameters in diastole, and E/A ratio of tricuspid valve (P = 0.047, P = 0.001, and P = 0.021, respectively). A significant difference was also observed between the two groups in terms of septal S´ and E´ parameters (P = 0.004 and P = 0.002, respectively). Moreover, diminished E/A ratio of tricuspid valve annulus was related to the increased duration of the disease. Even though left ventricular hypertrophy occurred in the patients, no significant increase was observed in BNP values.
The results indicated that M-mode, two-dimensional, pulsed Doppler, and TDI echocardiography might efficiently evaluate cardiac function in patients with preserved ejection fraction. However, BNP measurement might not be useful for screening of cardiac function.