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 Blinddarmentzündungen bei Kindern: Ultraschall als erstes Mittel zur exakten Diagnose
28.11.2019 | Deutsche Gesellschaft für Ultraschall in der Medizin (DEGUM)

nachricht Biologen der TU Dresden untersuchen Spermienqualität anhand ihres Stoffwechsels
28.11.2019 | Technische Universität Dresden

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: Hochgeladenes Ion bahnt den Weg zu neuer Physik

In einer experimentell-theoretischen Gemeinschaftsarbeit hat am Heidelberger MPI für Kernphysik ein internationales Physiker-Team erstmals eine Orbitalkreuzung im hochgeladenen Ion Pr9+ nachgewiesen. Mittels einer Elektronenstrahl-Ionenfalle haben sie optische Spektren aufgenommen und anhand von Atomstrukturrechnungen analysiert. Ein hierfür erwarteter Übergang von nHz-Breite wurde identifiziert und seine Energie mit hoher Präzision bestimmt. Die Theorie sagt für diese „Uhrenlinie“ eine sehr große Empfindlichkeit auf neue Physik und zugleich eine extrem geringe Anfälligkeit gegenüber externen Störungen voraus, was sie zu einem einzigartigen Kandidaten zukünftiger Präzisionsstudien macht.

Laserspektroskopie neutraler Atome und einfach geladener Ionen hat während der vergangenen Jahrzehnte Dank einer Serie technologischer Fortschritte eine...

Im Focus: Highly charged ion paves the way towards new physics

In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.

Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...

Im Focus: Ultrafast stimulated emission microscopy of single nanocrystals in Science

The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.

Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...

Im Focus: Wie Graphen-Nanostrukturen magnetisch werden

Graphen, eine zweidimensionale Struktur aus Kohlenstoff, ist ein Material mit hervorragenden mechanischen, elektronischen und optischen Eigenschaften. Doch für magnetische Anwendungen schien es bislang nicht nutzbar. Forschern der Empa ist es gemeinsam mit internationalen Partnern nun gelungen, ein in den 1970er Jahren vorhergesagtes Molekül zu synthetisieren, welches beweist, dass Graphen-Nanostrukturen in ganz bestimmten Formen magnetische Eigenschaften aufweisen, die künftige spintronische Anwendungen erlauben könnten. Die Ergebnisse sind eben im renommierten Fachmagazin Nature Nanotechnology erschienen.

Graphen-Nanostrukturen (auch Nanographene genannt) können, je nach Form und Ausrichtung der Ränder, ganz unterschiedliche Eigenschaften besitzen - zum Beispiel...

Im Focus: How to induce magnetism in graphene

Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.

Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

VideoLinks
Industrie & Wirtschaft
Veranstaltungen

Analyse internationaler Finanzmärkte

10.12.2019 | Veranstaltungen

QURATOR 2020 – weltweit erste Konferenz für Kuratierungstechnologien

04.12.2019 | Veranstaltungen

Die Zukunft der Arbeit

03.12.2019 | Veranstaltungen

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

Kein Seemannsgarn: Hochseeschifffahrt soll schadstoffärmer werden

11.12.2019 | Ökologie Umwelt- Naturschutz

Vernetzte Produktion in Echtzeit: Deutsch-schwedisches Testbed geht in die zweite Phase

11.12.2019 | Informationstechnologie

Verbesserte Architekturgläser durch Plasmabehandlung – Reinigung, Vorbehandlung & Haftungssteigerung

11.12.2019 | Architektur Bauwesen

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