Wave Pressure is Higher in Atenolol-treated Individuals and Independently Predicts Cardiovascular Events in the Cafe Substudy of ASCOT

J.E. Davies, A. Malaweera, P.S. Lacy, K. Cruickshank, A. Stanton, D. Collier, H. Thurston, B. Williams, K.H. Parker, S.A.M. Thom, A.D. Hughes
2010 Artery Research  
Purpose: To investigate 1) the association between television (TV) viewing and arterial stiffness (AS); and 2) whether any such association is independent of other lifestyle risk factors (RFs), most notably vigorous habitual physical activity (HPA), and/or is explained by TV-time-related adverse associations with biological RFs. Methods: We investigated repeated measures (at ages 32 and 36) of TV time and other RFs among 373 subjects in whom stiffness of 3 large arteries was assessed with
more » ... assessed with ultrasonography at age 36. Generalized estimating equations were used to determine the average differences in TV time between subjects across sex-specific tertiles (T1-3) of the inversed carotid, brachial and femoral distensibility (DC) and compliance (CC) coefficients, and the carotid Young's elastic modulus (E inc ). Results: Compared with subjects in T1 (less stiff), those in T3 (stiffer arteries) of the carotid DC, CC and E inc spent more time (in min/day) [19.9 (95%CI:5.9;33.9), 16.7 (2.3;31.1) and 17.6 (3.7;31.5), respectively] on TV viewing during the 4 preceding years (Table, model 1). These differences were independent of vigorous HPA and other lifestyle RFs (model 2-3), and only in part (up to 31%) explained by TV-time-related associations with biological RFs (model 4). Qualitatively similar results were found for femoral, but not brachial, stiffness estimates. Discussion: TV time is associated with higher levels of carotid and femoral stiffness in young adults, independently of HPA and other RFs. Promotion of more physical activity but also less sedentarism (two distinct behaviours) should, therefore, be encouraged to prevent AS and related sequelae. Background: Wave reflection accounts for augmentation of aortic pressure, but most studies have failed to show an independent relationship between augmentation index (AIx) and cardiovascular (CV) events. We hypothesise this is because conventional pulse wave analysis does not distinguish wave pressure from that attributable to charging and recoil of the aorta. Aim: To identify if the wave pressure integral (WPI) is differentially affected by atenolol-vs. amlodipine-based therapy and is an independent predictor of CV events in the CAFE sub-study of the ASCOT trial. Methods: Radial pressure waveforms were acquired using Sphygmocor in 2070 subjects (63AE8 yrs; 1675 male) and WPI was calculated. A total of 134 CV events accrued over a median 3.4 years of follow up. Results: WPI was higher in the atenolol arm (786AE284 vs 744AE253 mmHg.s, p<0.001), despite similar brachial systolic BP (134AE16 vs 134AE14 mmHg, pZ0.78). WPI predicted total CV events (Hazard ratio Z2.5 [1.51-4.14], p<0.001), and remained significant after adjustment for age, sex, treatment, number of CV risk factors, brachial BP, central systolic pressure, central pulse pressure, AIx and heart rate. Central systolic pressure and AIx did not predict CV events. Conclusions: Wave pressure was higher in the atenolol arm and independently predicted CV events in the CAFE study. WPI is easily calculated from the BP waveform and may have potential for optimization of therapy and risk evaluation. P9.04 Background: Arterial stiffness is an independent predictor of cardiovascular events and mortality in hypertensive patients. The influence of different antihypertensive drug classes on improving arterial stiffness beyond blood pressure reduction was not well demonstrated because of lack of power studies related to this subject. We aim to determine if the artery stiffness can be improved due to antihypertensive treatment independently of blood pressure lowering. Methods: We conducted a meta-analysis of individual data from 15 randomized, controlled, double-blind, parallel group trials performed in our laboratory between 1987 and 1994. The primary endpoint was the changes in carotid-femoral pulse wave velocity (PWV) after treatment in 294 patients with mild to moderate essential hypertension untreated. Treatments tested were placebo (n Z 88), angiotensin converting enzyme inhibitors (ACEI) (n Z 75), calcium antagonists (CA) (n Z 75), beta-blocker (n Z 30), and diuretic (n Z 26). Results: In the short and long-term trials, PWV decreased significantly by -0.75 m/s and -1.3 m/s in the active treatment group compared to by +0.17 m/s and -0.44 m/s in the placebo group respectively. Active treatment was independently related to the changes in PWV and explained 5% and 4% of the variance in the short and long-term trials respectively. In the short-term trials, ACEI was more effective than CA and placebo on improving arterial stiffness. In the long-term trials, ACEI, CA, beta-blocker, and diuretic reduced significantly PWV compared to placebo. Conclusion: Our study shows that antihypertensive treatment improves the arterial stiffness beyond its effect on blood pressure.
doi:10.1016/j.artres.2010.10.095 fatcat:46cbifqj2bbvdbwugfbxqy6i3m