Preliminary, randomized, double-blinded, placebo-controlled cross-over study with resveratrol in hypertensive patients.

Hypertension is a debilitating disease affecting the population worldwide. Novel therapeutic strategies that complement the current management of hypertension will reduce the disease burden. Our randomized, cross-over, double-blinded, placebo-controlled trial studied the efficacy of plant polyphenol resveratrol (trans-3, 5, 4'-trihydroxystilbene) in managing blood pressure in pre-hypertensive and stage-1-hypertensive patients. Participants with pre-hypertension (diastolic and systolic blood pressure (BP), 80-89 mmHg and 120-139 mmHg, respectively) and 30 participants with stage-1-hypertension (diastolic and systolic BP, 90-99 mmHg and 140-159 mmHg, respectively) were assigned to receive 500 mg resveratrol, twice daily for 4 weeks, orally) or placebo twice daily for 4 weeks) in a 2 × 2 cross-over design (4 weeks treatment-4 weeks washout-4 weeks treatment). The BP of each participant was recorded every week during the study. Data analysis using the multivariable model revealed that resveratrol's effects on systolic and diastolic BP were not statistically significantly superior to those of placebo. Nitric oxide (NO) was considerably higher in the resveratrol-treated group than in the placebo-treated group. In this preliminary study, Resveratrol supplementation for a short duration enhances nitric oxide production but does not significantly lower blood pressure in pre-hypertension or stage 1 hypertension patients. This finding remains exploratory and needs confirmation through larger, long-term clinical trials. Trial registration: IRCT201407078129N7, first trial registration date: 15/08/2014.