Idiopathic deep venous thrombosis and arterial endothelial dysfunction in the elderly

Arterial and venous thrombosis have always been regarded as different pathologies and epidemiological studies have examined the association between venous thrombosis and indicators of atherosclerosis and/or arterial thromboembolic events. We measured the flow-mediated dilation (FMD), a well-known marker of arterial endothelial dysfunction, in young-middle-aged and old-aged patients with and without unprovoked deep venous thrombosis (DVT). The aim of this study was to investigate whether DVT was a significant predictor for impaired FMD, considering all the patients and young-middle-aged (age < 65 years) and old-aged (age ≥ 65 years) patients separately. FMD was measured in the brachial artery on a population of 120 subjects with the same atherosclerosis risk factors, 68 male and 52 female, 70 young-middle-aged subjects (mean age ± SD 49.5 ± 10.5 years) and 50 old-aged subjects (76.2 ± 7.7 years). Patients with DVT showed a significant decrease of FMD compared to patients without DVT (6.8 ± 5.5% vs. 10.9 ± 3.5%, p < 0.001). Moreover, old-aged patients showed a significant decrease of FMD compared to the young-middle-aged subjects (7.4 ± 4.1% vs. 9.8 ± 5.3%, p = 0.005). In the whole study population, DVT was strongly associated with FMD (risk factors adjusted β = -4.14, p < 0.001). A significant interaction between age and the presence of DVT on predicting FMD was found (p = 0.003) suggesting a differential behavior of DVT as predictor of FMD. In young-middle-aged group, multivariate model confirmed that DVT was the most significant predictor of continuous FMD (β = -6.06, p < 0.001). On the contrary, DVT was no more a predictor of FMD in the old age group (β = -0.73, p = 0.556). Furthermore, old-aged patients without DVT showed a statistically significant decrease of FMD compared to the young-middle-aged subjects without DVT (8.2 ± 2.1% vs. 12.6 ± 2.7%, p<0.001) and old-aged patients with DVT showed a not statistically significant decrease of the FMD compared to the young-middle-aged patients with DVT (6.7 ± 5.3% vs. 6.8 ± 5.7%, p = 0.932). In conclusion, young-middle-aged patients with spontaneous DVT show an impaired FMD, whereas this impairment in old-aged subjects is evident independently from the presence or absence of DVT. Aging per se may be associated with physiologic abnormalities in the systemic arteries and with endothelial dysfunction.