Structural and functional cardiac abnormalities in adolescent girls with poorly-controlled type 2 diabetes mellitus

Abstract

Objective: Type 2 diabetes is associated with left ventricular (LV) hypertrophy (LVH) and diastolic dysfunction, which may eventually lead to clinical heart failure (HF). We sought to determine the cardiovascular effects of adolescent-onset type 2 diabetes.

Research Design and Methods: We recruited diabetic girls (8 type 2, 11 type 1) from a hospital diabetes service and non-diabetic controls (9 lean, 11 overweight) from the diabetic subjects' schools. Echocardiography and measurements were performed by single observer, blinded to subject group allocation, and included m-mode LV dimensions, 2-dimensional LV mass (LVM), Doppler diastolic flows, estimation of LV filling pressure and systolic longitudinal motion. LVM was indexed to height and fat free body mass (FFM). ANOVA was used to compare the groups.

Results: The groups were similar in age and height, but significant differences in body composition were observed. Subjects with type 2 diabetes had larger LV dimensions and LVM, which persisted when indexed to height. Diastolic filling was impaired in both diabetic groups and systolic longitudinal function was lower in the type 2 diabetes group. Half of the group with type 2 diabetes met published criteria for LVH and LV dilatation; 25% had evidence of elevated LV filling pressure in association with structural abnormalities.

Conclusions: This study has demonstrates pre-clinical abnormalities of cardiac structure and function in adolescent girls with type 2 diabetes, despite short duration of diabetes and highlights the potential high cardiovascular risk occurring in adolescent type 2 diabetes.