NLM Director's Comments Transcript
Prehypertension & Stroke Risk: 10/31/2011

URL of this page: http://www.nlm.nih.gov/medlineplus/podcast/transcript103111.html

<><><>

Greetings from the National Library of Medicine and MedlinePlus.gov
Regards to all our listeners!
I'm Rob Logan, Ph.D. senior staff National Library of Medicine for Donald Lindberg, M.D, the Director of the U.S. National Library of Medicine.
Here is what's new this week in MedlinePlus.

The meta-analysis of 512,000 adults within 12 different studies found persons with prehypertension were 55 percent more likely to experience a stroke compared to persons with normal blood pressure levels.

The authors explain there is long-standing evidence that the risk of a stroke is significantly increased if an adult has high blood pressure. However, the current systematic review is the first to suggest stroke risk additionally is elevated significantly if an adult has slightly higher than normal blood pressure.

The study suggests between 25 to 45 percent of Americans have prehypertension (or slightly higher than normal blood pressure). In a story about the study's findings, Health Day reported previous research found about 25 percent of Americans experience prehypertension. So, the study suggests the number of Americans with prehypertension may be higher than past estimates.

MedlinePlus.gov's high blood pressure health topic page reports hypertension (or higher than normal blood pressure) is defined as a systolic pressure of 140 or higher and diastolic pressure of 90 or higher. Systolic refers to blood pressure when the heart is pumping; diastolic refers to the pressure between heart beats. This explains why blood pressure is often communicated (hypothetically) as '120 over 80.'

By comparison, normal blood pressure is defined as systolic pressure below 120 and a diastolic pressure of less than 80. Pre-hypertension falls in the middle. It is defined as a systolic pressure of 120 to 139 and a diastolic pressure of 80 to 89.

Incidentally, prehypertension was introduced as a clinical category by the National Heart, Lung, and Blood Institute in 2003. Since prehypertension is rather new in the medical literature, this may explain why research is still emerging about its health impacts.

Other interesting findings in the Neurology study suggest:

Adults below age 65 with prehypertension were almost 68 percent more likely to have a stroke compared with men and women with normal blood pressure.
Within prehypertension's ranges, adults with blood pressure at its lower systolic levels from 120-129 experienced a 22 percent higher risk of stroke compared to those with normal blood pressure levels. However, adults with systolic blood pressure levels between 130-139 experienced a 79 percent higher risk of stroke compared to persons with normal blood pressure levels.

The study's six authors note the findings suggest there is a pressing need for more research - especially with randomized controls - about prehypertension's health impacts. The authors suggest future studies should explore the extent that prehypertension's impact is associated with demographic characteristics, such as age, gender, or race. The authors additionally suggest that researchers take more than a single day measurement of patient blood pressure in future studies.

Despite the current study's limitations the authors conclude (and we quote): the results of this systematic review probably represent the most precise and accurate estimate of the strength of the relation between prehypertension and incident stroke currently available' (end of quote).

Meanwhile, MedlinePlus.gov's high blood pressure health topic page provides comprehensive information about the diagnosis/symptoms, treatment, and disease management of blood pressure.

A link to specific information about the association between blood pressure and stroke (provided by the American Heart Association) is available in the 'related issues' section. The 'related issues' section also contains a separate link (provided the Mayo Foundation for Medical Education and Research) specifically devoted to information about prehypertension.

MedlinePlus.gov's high blood pressure health topic page additionally contains research summaries, which are available in the 'research' section. Links to the latest pertinent journal research articles are available in the 'journal articles' section. Links to related clinical trials that may be occurring in your area are available in the 'clinical trials' section.

To find MedlinePlus.gov's high blood pressure health topic page, type 'blood pressure' in the search box on MedlinePlus.gov's home page, then, click on 'high blood pressure (National Library of Medicine).'

MedlinePlus.gov also has a health topic page devoted to stroke. To find MedlinePlus.gov's stroke health topic page, type 'stroke' in the search box on MedlinePlus.gov's home page, then, click on 'stroke (National Library of Medicine).'

Before I go, this reminder……. MedlinePlus.gov is authoritative. It's free. We do not accept advertising …
and is written to help you.

To find MedlinePlus.gov, just type in 'MedlinePlus.gov' in any web browser, such as Firefox, Safari, Netscape, Chrome or Explorer. To find Mobile MedlinePlus.gov, just type 'Mobile MedlinePlus' in the same web browsers.

We encourage you to use MedlinePlus and please recommend it to your friends. MedlinePlus is available in English and Spanish. Some medical information is available in 43 other languages.

Your comments about this or any of our podcasts are always welcome. We welcome suggestions about future topics too!
Please email Dr. Lindberg anytime at: NLMDirector@nlm.nih.gov
That's NLMDirector (one word) @nlm.nih.gov
A written transcript of recent podcasts is available by typing 'Director's comments' in the search box on MedlinePlus.gov's home page.
The National Library of Medicine is one of 27 institutes and centers within the National Institutes of Health. The National Institutes of Health is part of the U.S. Department of Health and Human Services.
A disclaimer –the information presented in this program should not replace the medical advice of your physician. You should not use this information to diagnose or treat any disease without first consulting with your physician or other health care provider.
It was nice to be with you. I look forward to meeting you here next week.
NLM Director's Comments Transcript - Prehypertension & Stroke Risk: MedlinePlus
Adults with prehypertension, or slightly higher than normal blood pressure, have an increased risk of stroke, finds a comprehensive analysis of previous research recently published in the journal Neurology.