Background: Daily glucose variability may contribute to vascular complication development irrespective of mean glucose values. The incremental glucose peak (IGP) during an oral glucose tolerance test (OGTT) can be used as a proxy of glucose variability. We investigated the association of IGP with arterial stiffness, arterial remodeling, and microvascular function, independent of HbA1c and other confounders.
Methods: IGP was calculated as the peak minus baseline plasma glucose value during a seven-point OGTT in 2758 participants (age: 60 ± 8 years; 48% women) of The Maastricht Study, an observational population-based cohort. We assessed the cross-sectional associations between IGP and arterial stiffness (carotid-femoral pulse wave velocity [cf-PWV], carotid distensibility coefficient [carDC]), arterial remodeling (carotid intima-media thickness [cIMT]; mean [CWSmean] and pulsatile [CWSpuls] circumferential wall stress), and microvascular function (retinal arteriolar average dilatation; heat-induced skin hyperemia) via multiple linear regression with adjustment for age, sex, HbA1c, cardiovascular risk factors, lifestyle factors, and medication use.
Results: Higher IGP was independently associated with higher cf-PWV (regression coefficient [B]: 0.054 m/s [0.020; 0.089]) and with higher CWSmean (B: 0.227 kPa [0.008; 0.446]). IGP was not independently associated with carDC (B: - 0.026 10-3/kPa [- 0.112; 0.060]), cIMT (B: - 2.745 µm [- 5.736; 0.245]), CWSpuls (B: 0.108 kPa [- 0.054; 0.270]), retinal arteriolar average dilatation (B: - 0.022% [- 0.087; 0.043]), or heat-induced skin hyperemia (B: - 1.380% [- 22.273; 19.513]).
Conclusions: IGP was independently associated with aortic stiffness and maladaptive carotid remodeling, but not with carotid stiffness, cIMT, and microvascular function measures. Future studies should investigate whether glucose variability is associated with cardiovascular disease.
Keywords: Arterial remodeling; Arterial stiffness; Glucose metabolism status; Glucose variability; Oral glucose tolerance test.