E. Azevedo 1, S. Penas 2, C. Ferreira 1, L. Martins 2, A. Campilho 3, J. Polónia 4
1 Department of Neurology,
2 Department of Ophthalmology, São João Hospital Center and Faculty of Medicine of University of Porto,
3 Institute of Biomedical Engineering, University of Porto,
4 Arterial Hypertension Clinic of Hospital Pedro Hispano and Faculty of Medicine of University of Porto – Porto, Portugal
Objective: Diabetes mellitus (DM) leads to accelerated progression of arteriosclerosis in comparison to non-diabetic patients (non-DM). Retinopathy is a major microvascular complication of DM remaining a leading cause of blindness. Aortic stiffness and an increase in carotid artery intima-media thickness (IMT) are macrovascular complications that are associated with increased cardiovascular morbidity-mortality. It has been suggested that in DM blood pressure levels are more determinant than glycemic control of macrovascular lesions whereas retinopathy is more dependent on glycemic control.
Material and Methods: We compared the macrovascular damages – aortic stiffness by pulse wave velocity (PWV) and carotid plaques and IMT by duplex ultrasound – and hypertensive retinopathy lesions (early and late stages) by fundus photograph between type 2 DM and non-DM hypertensive subjects with similar age and 24h-ambulatory BP values.
Results: Hypertensive patients with DM (n=26, 10 female) and non-DM (n=33, 17 female) did not differ for age (62±8 vs 58±13 y), BMI (29.6±4.0 vs 29.1±5.3 kg/m2), 24h BP (144/84±15/11 vs 137/82±16/10 mm Hg) and for PWV (11.7±2.0 vs 11.1±1.7 m/s) and IMT max (0.92±0.16 vs 0.86±0.19 mm) IMT average (0.77±0.13 vs 0.72±0.17 mm) and presence of carotid plaques (73% vs 53%) (all p>0.19). In contrast DM showed a higher percentage of indices of late stage hypertensive retinopathy than non-DM subjects (65.4% vs 33.4%, p<0.03). Significant correlations were found between PWV and 24h-SBP (0.330, p< 0.02) and between IMT and 24h pulse pressure (r=0.330, p<0.02) but no association was found between 24h BP values and retinopathy lesions.
Discussion: In DM macrovascular damage is particularly dependent on blood pressure levels, whereas the severity of hypertensive retinopathy is clearly related with DM condition.
Key words: arterial hypertension, carotid intima-media thickness, diabetes mellitus, retina.