Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Saw palmetto no better than placebo for enlarged prostate

09.02.2006


Prospective double-blind study of 225 men shows no benefit to widely-used herbal medication



Saw palmetto, an herbal extract commonly taken to improve urinary symptoms in men with enlargement of the prostate gland, is no more effective than a placebo, according to a new study.

... mehr zu:
»BPH »MPH »PhD »UCSF


The year-long, double-blind study of 225 men was led by Stephen Bent, MD, a staff physician at the San Francisco VA Medical Center, and Andrew Avins, MD, MPH, of the Northern California Kaiser Permanente Division of Research.

The results are published in the February 9, 2006 issue of the New England Journal of Medicine.

In their study, the researchers randomly assigned patients with enlargement of the prostate, also known as or benign prostate hyperplasia or BPH, to take either saw palmetto or a placebo twice a day for one year. Subjects returned at regular intervals to be assessed for symptoms and side effects. Symptoms were assessed according to a standard symptom score for BPH and objective measures of urinary function.

"If you look at the change in symptoms over time between the two groups, it was almost identical," reports Bent, who is also an assistant professor of medicine at the University of California, San Francisco. "There was no statistically significant difference at any time point during the study."

The researchers also looked at subgroups of patients – those with more and less severe symptoms and those with larger and smaller prostates – and found no difference in any of the subgroups between the herbal extract and placebo.

"The results of this study clearly do not support a strong clinical benefit of saw palmetto for BPH," concludes Bent. "However, whether other doses, formulations, or patient populations might respond differently is unknown."

The researchers estimate that saw palmetto is used by over two million men in the United States for treatment of BPH, which is said by the National Institutes of Health to affect more than 50 percent of men over 60 and upwards of 90 percent of men over 70.

Bent acknowledges that the study results are surprising, since many earlier studies concluded that saw palmetto is effective against BPH. However, he points out a number of differences between the current study and earlier research.

"Prior studies were generally small in size and short in duration," he says. "Plus, the vast majority of them did not use the standard symptom score that we used for assessing the severity of BPH," which is now commonly used to judge the efficacy of pharmaceutical drugs for treatment of the condition.

Another potential problem with earlier studies has to do with the nature of saw palmetto itself, according to Bent. "This is a very pungent herb, and it took our research team a long time to create a placebo that convincingly duplicates its strong smell and taste. We suspect that prior trials didn’t adequately address that problem." As a result, he says, "it’s possible that some of the positive findings in earlier work may be due to the fact that the blinding wasn’t adequate." In other words, patients in those studies knew whether they were taking the herb or the placebo, and "someone who’s taking something that’s smelly and likely to be the plant extract is perhaps more likely to report a benefit than someone who’s taking an odorless and tasteless tablet."

At the end of the current study, 40 percent of patients in the saw palmetto group believed they were taking the herbal extract versus 46 percent in the placebo group, demonstrating that the blinding was adequate, says Bent.

Bent notes that his research team took pains to select an herbal product that matched the levels of fatty acids and sterols – commonly believed to be saw palmetto’s active ingredients – found in most commonly available commercial preparations of the herb.

Almost all prior studies of saw palmetto used exactly the same dose, says Bent – 160 milligrams twice a day – and the current study used that dose as well. He notes that such consistency of dose is not typical among studies of most other herbal medications.

The current study subjects reported no statistically significant side effects from saw palmetto.

Bent cautions that while the study is strongly indicative, it is not conclusive. "This is a surprising finding that contradicts the weight of prior evidence," he observes. "There is good reason for other researchers to conduct another study to validate these results, taking care that blinding is done carefully once again."

In addition, says Bent, "Some people believe that higher doses may be potentially effective, and that’s an area that we did not address."

A major new NIH-funded study of saw palmetto and another commonly-used herbal treatment for BPH is currently in the final planning stages, according to Avins, who is a co-author of the current study. The new study will involve several hundred patients at 11 centers nationwide, and researchers hope it will shed more definitive light on the questions of adequate doses and other potentially useful natural treatments for BPH, says Avins.

Other co-authors of the current study include Christopher Kane, MD, and Katsuto Shinohara, MD, of SFVAMC; John Neuhaus, PhD, and Esther S. Hudes, PhD, MPH, of UCSF; and Harley Goldberg, DO, of UCSF and KPNC.

Steve Tokar | EurekAlert!
Weitere Informationen:
http://www.ncire.org

Weitere Berichte zu: BPH MPH PhD UCSF

Weitere Nachrichten aus der Kategorie Studien Analysen:

nachricht Studie zu Bildungsangeboten für die Industrie 4.0 in Österreich
05.02.2018 | Fachhochschule St. Pölten

nachricht Schildkrötengehirne sind komplexer als gedacht
05.02.2018 | Eberhard Karls Universität Tübingen

Alle Nachrichten aus der Kategorie: Studien Analysen >>>

Die aktuellsten Pressemeldungen zum Suchbegriff Innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Eine Frage der Dynamik

Die meisten Ionenkanäle lassen nur eine ganz bestimmte Sorte von Ionen passieren, zum Beispiel Natrium- oder Kaliumionen. Daneben gibt es jedoch eine Reihe von Kanälen, die für beide Ionensorten durchlässig sind. Wie den Eiweißmolekülen das gelingt, hat jetzt ein Team um die Wissenschaftlerin Han Sun (FMP) und die Arbeitsgruppe von Adam Lange (FMP) herausgefunden. Solche nicht-selektiven Kanäle besäßen anders als die selektiven eine dynamische Struktur ihres Selektivitätsfilters, berichten die FMP-Forscher im Fachblatt Nature Communications. Dieser Filter könne zwei unterschiedliche Formen ausbilden, die jeweils nur eine der beiden Ionensorten passieren lassen.

Ionenkanäle sind für den Organismus von herausragender Bedeutung. Wenn zum Beispiel Sinnesreize wahrgenommen, ans Gehirn weitergeleitet und dort verarbeitet...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Erste integrierte Schaltkreise (IC) aus Plastik

Erstmals ist es einem Forscherteam am Max-Planck-Institut (MPI) für Polymerforschung in Mainz gelungen, einen integrierten Schaltkreis (IC) aus einer monomolekularen Schicht eines Halbleiterpolymers herzustellen. Dies erfolgte in einem sogenannten Bottom-Up-Ansatz durch einen selbstanordnenden Aufbau.

In diesem selbstanordnenden Aufbauprozess ordnen sich die Halbleiterpolymere als geordnete monomolekulare Schicht in einem Transistor an. Transistoren sind...

Im Focus: Quantenbits per Licht übertragen

Physiker aus Princeton, Konstanz und Maryland koppeln Quantenbits und Licht

Der Quantencomputer rückt näher: Neue Forschungsergebnisse zeigen das Potenzial von Licht als Medium, um Informationen zwischen sogenannten Quantenbits...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

VideoLinks
Industrie & Wirtschaft
Veranstaltungen

Aachener Optiktage: Expertenwissen in zwei Konferenzen für die Glas- und Kunststoffoptikfertigung

19.02.2018 | Veranstaltungen

Konferenz "Die Mobilität von morgen gestalten"

19.02.2018 | Veranstaltungen

Von Bitcoins bis zur Genomchirurgie

19.02.2018 | Veranstaltungen

VideoLinks
Wissenschaft & Forschung
Weitere VideoLinks im Überblick >>>
 
Aktuelle Beiträge

Die Zukunft wird gedruckt

19.02.2018 | Architektur Bauwesen

Fraunhofer HHI präsentiert neueste VR- und 5G-Technologien auf dem Mobile World Congress

19.02.2018 | Messenachrichten

Stabile Gashydrate lösen Hangrutschung aus

19.02.2018 | Geowissenschaften

Weitere B2B-VideoLinks
IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics