[Usefulness of phyto-oestrogens in reduction of blood pressure. Systematic review and meta-analysis].
OBJECTIVE
To determine whether treatment with phyto-oestrogens or soya protein succeeds in lowering blood pressure.


METHODS
A systematic review, evaluating all the observation studies and clinical trials, was conducted, followed by a meta-analysis to evaluate blood pressure variations in patients treated with phyto-oestrogens. SEARCH: The search strategy adopted used the terms "phyto-oestrogens," "soya meals," "hypertension," and "blood pressure."


METHODS
The data bases MEDLINE, EMBASE, Cochrane, OVID were used, without time or language restrictions. References in the relevant articles were searched for manually.


METHODS
Two independent reviewers analysed the studies found in the search.


METHODS
The Jadad scale was used for the clinical trials and the numerical data in the text or referred to in tables were extracted. Evaluation was made of which observational and experimental articles showed a drop in blood pressure with phyto-oestrogens and which did not. In the meta-analysis, data on sample size, difference in blood pressure before and after intervention and standard deviation were extracted from each study. The weighted difference of means was used with the model of randomised effects. The Review Manager v4.2.9 programme was used.


RESULTS
No significant variations in blood pressure were found, whether systolic (-1.20 mm Hg; 95% CI, -2.80 to 0.41 mm Hg) or diastolic (-1.31 mm Hg; 95% CI, -2.73 to 0.11). If there were any variations, they are clinically of little importance. There was also an important degree of both statistical and clinical heterogeneity.


CONCLUSIONS
There are no statistically significant or clinically important differences in blood pressure between patients treated with phyto-oestrogens and those not treated.
Rosero Arenas
M Angeles
MA
Medicina de Familia, Centro de Salud Economista Gay, Valencia, España. mangelesymangel@hotmail.com
Rosero Arenas
Esteban
E
Portaceli Armiñana
M Amparo
MA
García García
Miguel Angel
MA
D001794:Blood Pressure / Q000187:drug effects*; D003971:Diastole / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D048789:Phytoestrogens / Q000627:therapeutic use*; D045730:Soy Foods; D013599:Systole / Q000187:drug effects
D048789:Phytoestrogens