Adipokines as atherothrombotic risk factors in obese subjects: Associations with haemostatic markers and common carotid wall thickness.

BACKGROUND AND AIMS: Some crucial associations between obesity-related altered adipokine levels and the main factors of atherosclerotic, atherothrombotic processes are not fully known. We analysed the relationships of classic adipokines, namely leptin, resistin, adiponectin, tumour necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) with the markers of platelet activation, including mean platelet volume (MPV), platelet surface/soluble P-selectin, platelet-derived microparticles (PMPs), the parameters of coagulation abnormalities and common carotid intima-media thickness (IMT) in obese patients with or without atherosclerotic comorbidities in comparison to age- and sex-matched controls. METHODS AND RESULTS: We enrolled 154 obese individuals, including 98 suffering from atherosclerotic concomitant conditions, 56 free of atherosclerotic comorbidities and 62 healthy controls. Plasma levels of leptin, resistin, adiponectin, TNF-α, IL-6, soluble P-selectin, and plasminogen activator inhibitor-1 antigen (PAI-1 ag) were analysed by ELISA. Platelet surface P-selectin and PMPs were measured by flow cytometry. IMT was detected by ultrasonography. Adipokines were closely associated with markers of platelet hyperactivity, hypercoagulability, hypofibrinolysis and IMT. Significant independent associations were found between leptin and platelet count (p < 0.0001), MPV (p = 0.019), PMPs (p < 0.0001), fibrinogen (p = 0.001), factor VIII (FVIII) activity (p = 0.035); adiponectin and PAI-1 ag (p = 0.035); resistin and soluble P-selectin (p = 0.002); TNF-α and PAI-1 ag (p < 0.0001); and IL-6 and fibrinogen (p = 0.011). Finally, leptin (p = 0.0005), adiponectin (p = 0.019), IL-6 (p = 0.001), MPV (p = 0.0003), PMP (p = 0.008), and FVIII activity (p = 0.043) were independent predictors of IMT. CONCLUSION: Overall, we suggest that in obese subjects altered adipokine levels play a key role in common carotid atherosclerosis both directly and through haemostatic parameters.

Transcranial Doppler monitoring in hypertensive patients during physical exercise.

PURPOSE: To evaluate the diagnostic value of a combined method, i.e. ergometer cycling with continuous bilateral transcranial Doppler monitoring (TCD) to detect cerebral hemodynamic abnormalities in recently diagnosed hypertensive patients. METHODS: 30 neurologically symptom-free, nontreated patients with essential hypertension and 30 age- and sex-matched controls were studied. Carotid ultrasound, resting ECG and blood parameters were investigated. Cycling ergometry was performed according to the WHO protocol. Blood pressure, heart rate, end-tidal CO2 (etCO2) and bilateral middle cerebral artery (MCA) blood flow velocity (MV) were monitored. RESULTS: At rest, MV in the MCA did not differ significantly between controls and hypertensive subjects. MV continuously increased in controls until the end of loading whereas a plateau was reached at 4 min in hypertensive subjects. During 6 min of cycling, the time course of absolute values of MV in the MCA and that of the changes in the ratio of mean velocity/end-tidal CO2 (DeltaMV/DeltaetCO2) differed significantly between hypertensive subjects and controls (p = 0.03 and p = 0.02, respectively). CONCLUSION: Ergometer cycling combined with TCD revealed altered vasoreactivity, therefore this may be a sensitive method for the detection of early hemodynamic impairment in nontreated hypertensive subjects.