Efficacy of olive leaf extracts in controlling blood pressure in hypertensive patients: a double-blind randomized clinical trial.

Objectives: The aim of this trial was to assess the effects of olive leaf extract (OLE) on blood pressure (BP) control in patients treated for hypertension.

Methods: This is multicenter randomized, double-blind, placebo-controlled trial including 621 participants who were randomly assigned to receive either oral OLE ( n  = 307) or placebo ( n  = 314). The primary outcome was the change in 24-h SBP and DBP from baseline to week-12. Secondary outcomes included the change in BP load (BPL), BP variability (BPV), metabolic parameters, C-reactive protein (CRP), and body weight.

Results: OLE significantly reduced 24-h SBP compared to baseline and placebo group [respectively -6.4 mmHg (95% confidence interval, 95% CI -10 to -2.1) and -1.5 mmHg (95% CI -3.9 to 0.51); P  < 0.01]. In OLE group, systolic BPL decreased from 53.9% at baseline to 42.2% at 12-week ( P  = 0.03); in placebo group, it did not change significantly ( P  = 0.55). Diastolic BPL decreased from 30.7 to 21.2% ( P  = 0.03) in OLE group and did not change significantly in placebo group ( P  = 0.12). In OLE group, systolic BPV did not change significantly between baseline and week-12 [+2%; P  = 0.23] while diastolic BPV significantly decreased [-13.3%; P  = 0.04]. In placebo group, BPV did not change significantly at week-12 compared to baseline. OLE was associated with improvement in lipid profile and a significant reduction in blood glucose, triglycerides, CRP, and body weight. No significant adverse events were reported.

Conclusion: OLE can decrease 24-h BP, BPL, and diastolic BPV with improvement of lipid profile, systemic inflammation, and body weight in hypertensive patients.