Strong evidence has secured aging as a powerful predictor of both cardiovascular risk and endothelial dysfunction, yet specific treatment is not available. We tested the hypothesis that vascular responsiveness to flavanol-rich cocoa increases with advancing age. We have previously shown that flavanol-rich cocoa induced peripheral vasodilation, improving endothelial function via a nitric oxide (NO)-dependent mechanism.
We studied blood pressure and peripheral arterial responses to several days of cocoa in 15 young (< 50 years) and 19 older (> 50) healthy subjects.
The nitric oxide synthase (NOS) inhibitor Nω-nitro-L-arginine-methyl-ester (L-NAME) induced significant pressor responses following cocoa administration only among the older subjects: systolic blood pressure (SBP) rose 13 ± 4 mmHg, diastolic blood pressure (DBP) 6 ± 2 mmHg (P = 0.008 and 0.047, respectively); SBP was significantly higher in the older subjects (P < 0.05). Flow-mediated vasodilation, measured by tonometry in the finger, was enhanced with flavanol-rich cocoa in both groups, but significantly more so among the old (P = 0.01). Finally, basal pulse wave amplitude (PWA) followed a similar pattern. Four to six days of flavanol-rich cocoa caused a rise in PWA in both groups. At peak vasodilation following acute cocoa intake on the final day, both groups showed a further, significant rise in PWA. The response in the older subjects was more robust; P < 0.05. L-NAME significantly reversed dilation in both groups.
Flavanol-rich cocoa enhanced several measures of endothelial function to a greater degree among older than younger healthy subjects. Our data suggest that the NO-dependent vascular effects of flavanol-rich cocoa may be greater among older people, in whom endothelial function is more disturbed.
aDepartments of Medicine
bRadiology, Harvard Medical School and the Brigham and Women's Hospital, Boston, Massachusetts, USA
Received 5 January, 2006
Revised 16 February, 2006
Accepted 20 March, 2006
Correspondence and requests for reprints to Naomi D.L. Fisher MD, Endocrine-Hypertension Division, 221 Longwood Ave, Boston, MA 02115, USA Tel: +1 617 7325654; fax: +1 617 732 5764; e-mail: email@example.com
Sponsorship: N.D.L.F.'s research was supported in part by a National Institute on Aging (NIA) grant (RO3AG023896): ‘Flavanol-Rich Cocoa to Reverse Vascular Disease of Aging’. Both authors receive research grant support and are provided with flavanol-rich cocoa by Mars Inc., Hackettstown, New Jersey, USA.