The Location of Arterial Stiffening Differs in those with Impaired Fasting Glucose versus Diabetes: Implications for Left Ventricular Hypertrophy from the Multi-Ethnic Study of Atherosclerosis

Objective: To determine if middle aged and older individuals with impaired fasting glucose (IFG), but no clinical evidence of cardiovascular disease, exhibit abnormal changes in proximal thoracic aortic stiffness or left ventricular mass when compared to healthy counterparts. Research Design and Methods: From the Multi-Ethnic Study of Atherosclerosis, 2240 subjects with normal fasting glucose (NFG), 845 with IFG, and 414 with diabetes mellitus (DM), all aged 45 to 85 years without pre-existing coronary artery disease, underwent magnetic resonance imaging (MRI) determinations of total arterial and proximal thoracic aortic stiffness, and left ventricular mass. The presence or absence of other factors known to influence arterial stiffness were assessed. Results: After adjustment for clinical factors known to modify arterial stiffness, proximal thoracic aortic stiffness was not increased in those with IFG compared to those with NFG (1.90±0.05 vs 1.91±0.04 10mmHg, respectively, p=0.83). After accounting for clinical factors known to influence LV mass, LV mass was increased in those with DM relative to those with NFG (150.6±1.4 vs 145.8±0.81 gms [p<0.0009]), but not in those with IFG in comparison with NFG (145.2±1.03 vs 145.8±0.81 gms [p=0.56]). Conclusions: Middle aged and older individuals with with the pre-diabetes state of impaired fasting glucose do not exhibit abnormal proximal thoracic distensibility nor left ventricular hypertrophy relative to individuals with normal fasting glucose. For this reason, an opportunity may exist in those with IFG to prevent LV hypertrophy and abnormal aortic stiffness that is observed in middle and older age individuals with diabetes.