Increased urinary albumin excretion (UAE) is a potent predictor of future cardiovascular disease that corresponds to a state of generalized microvascular dysfunction, even below the threshold values usually considered for microalbuminuria. This holds true in patients with hypertension and particularly in those with diabetes mellitus (DM), in whom it is associated with macrovascular disease. At the same time, both hypertension and DM are associated with large artery stiffening, while hypertension often coexists with DM. In the present study, we investigated whether an association exists between UAE and arterial stiffness in newly-diagnosed patients with DM, independent of blood pressure (BP) levels.
Consecutive patients with newly-diagnosed DM were studied. All patients underwent office BP measurements and 24-hour ambulatory BP monitoring (Spacelabs 90207). Microalbuminuria was calculated from 24-hour urine samples. Arterial stiffness was evaluated with measurement of carotid-femoral pulse wave velocity (PWV) with applanation tonometry. Blood samples were drawn to estimate fasting glucose, glycated hemoglobin (HbA1c), lipid profile and renal function
A total of 65 patients aged 57 ± 11 years, 40 males and 25 females, with median DM duration of 2 months were included in the study. Fasting glucose was 121.5 (IR: 36) mg/dl and HbA1c 7.47 (IR: 2) %. The majority of patients (66.2%) had concomitant hypertension. In particular, 26 patients (40%) had a history of known hypertension with median duration of 8 (IR: 8) years, while 17 (26.2%) were simultaneously diagnosed with hypertension and DM. In our cohort, UAE was associated with fasting glucose (r = 0.294, p = 0.040), HbA1c (r = 0.426, p = 0.002), creatinine (r = 0.308, p = 0.035), glomerular filtration rate (r = 0.442, p = 0.002), office systolic (r = 0.403, p = 0.009) and diastolic (r = 0.447, p = 0.026) BP and PWV (r = 0.308, p = 0.031). However, in the multivariate analysis adjusting for BP and other variables, HbA1c (beta = 0.351, p = 0.015) was the only significant predictor of UAE, whereas the association between UAE and PWV no longer remained significant.
In newly-diagnosed patients with DM, hyperglycemia is an independent predictor of UAE, emphasizing the need for early and effective glycemic control. The observed association between UAE and arterial stiffening seems to be mediated by hyperglycemia and increased BP.
Aristotle University of Thessaloniki, Thessaloniki, Greece