Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Prominent hypertension specialists question results of TROPHY study on hypertension

30.10.2006
There may be as many as 70 million Americans with prehypertension. If these people can be treated pharmacologically to avoid or delay progression to clinical hypertension, there would be significant benefits to them and the overall health of the population.

The recent TROPHY study seems to lead to that conclusion. However, two editorials published in the November issue of the American Journal of Hypertension emphatically argue that the study is flawed and the conclusions reached are misleading.

Persons with prehypertension, generally defined as having a systolic blood pressure in the range of 120-139 mm Hg or a diastolic blood pressure of 80-89, will usually develop hypertension at the rate of about 10% per year. The recent Trial of Preventing Hypertension (TROPHY) examined whether treating patients with candesartan for two years resulted in a sustained reduction in the incidence of high blood pressure after the drug was discontinued. The TROPHY study concluded that the treatment significantly reduced the risk of incident hypertension over the four year study.

According to Stephen Persell, MD, MPH, TROPHY results are likely invalid. He and co-author David W. Baker, MD, MPH, both of the Feinberg School of Medicine at Northwestern University, argue that the study used an unusual definition of incident hypertension which could not accurately discriminate whether the drug had a sustained effect. They demonstrate that because blood pressure readings taken during active treatment were combined with readings taken after treatment had ended, a difference between treatment and placebo could appear even if blood pressures were identical after the treatment had ended. They also analyze how the results could be misleading due to the methods used to calculate the mean blood pressures.

In the second editorial, Jay I. Meltzer MD, Clinical Specialist in Hypertension in the Nephrology Division of the Columbia College of Physicians and Surgeons, also zeros in on the study endpoint. He argues that clinical practitioners would require a more realistic, classical definition of incident hypertension than was used in TROPHY.

Dr. Meltzer also identifies two other issues in the study. He explains, "Further straining the question of applicability is the confusion between what the authors said they would do and what they actually did. They renamed TROPHY a 'feasibility' study, without specifically defining the term. It usually means a pilot study, but TROPHY was not designed as a pilot…Clinicians rightly suspect bias when the trial language is changed post hoc to allow more accommodation to the data." Finally, he argues that the major conclusion that the drug did prevent the development of hypertension was compromised by the choice of an arbitrary endpoint.

Persell and Baker caution that "the consequences of drawing erroneous conclusions from studies of treatments to prevent progression from pre-hypertension to hypertension are enormous. An expert panel of statisticians and trial methodologists without ties to pharmaceutical companies should be convened to provide consensus recommendations for how future studies addressing the prevention of hypertension should be conducted and reported. Computer models should also be used to confirm that the study methodology would not make it appear that a treatment for prehypertension had sustained benefits when, in fact, none existed."

Dr. Meltzer is equally direct. "What conclusions might actually be appropriate? TROPHY proved that two years of candesartan treatment of patients with 'high normal' or 'prehypertension' did not prevent or delay the development of hypertension, but instead caused a 'slow unmasking.' Reasonable acceptance of the author's own predetermined guidelines for the interpretation of 'slow unmasking' would have necessitated publishing a negative study, which, paradoxically, could have been a great benefit to the hypertension literature. Instead, TROPHY was presented in a way that enables those who want to believe in the original idea despite the evidence against it, still can and still do. Even as the authors trumpet candesartan's success in the paper's conclusions and in public presentations, the conclusion section of TROPHY paradoxically states that they do not advocate treating the 25 million people with prehypertension, but don't explain why."

Yvonne Raiford | EurekAlert!
Further information:
http://www.elsevierhealth.com/

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>