Relations of insulin resistance and glycemic abnormalities to cardiovascular magnetic resonance measures of cardiac structure and function: the Framingham Heart Study.

Description

This study was undertaken to investigate the potential relationships of diabetes, insulin resistance, hyperinsulinemia/hyperglycemia with cardiac structure and function by using cardiovascular magnetic resonance (CMR). For that purpose, a total of 1,603 Framingham Heart Study Offspring participants (age=64±9 years; 55% women) underwent CMR to determine left ventricular mass (LVM), LVM to end-diastolic volume ratio (LVM/LVEDV), relative wall thickness (RWT), ejection fraction, cardiac output, and left atrial size. In age-adjusted models in both men and women, results showed that insulin resistance (HOMA-IR) was significantly and positively related to all cardiac indices. Similarly, glycemia categories were associated with all cardiac measures except ejection fraction. In multivariable models, the associations between LVM/LVEDV and HOMA-IR as well as glycemia categories were unchanged. However, associations of other cardiac measures and indices of glucose/insulin metabolism were mediated by body mass index. These results suggest an important contribution of hyperglycemia and insulin resistance in concentric LV remodelling, but also demonstrated that several associations between altered glucose/insulin homeostasis and abnormal cardiac measures were largely mediated by elevated body mass index.