Nav: Home

Sodium intake associated with increased lightheadedness in context of DASH-sodium trial

February 08, 2019

BOSTON - Lightheadedness with standing, otherwise known as postural lightheadedness, results from a gravitational drop in blood pressure and is common among adults. While mild in many adults, it has been cited as an important contributing factor in some harmful clinical events, such as falls. As a result, greater sodium intake is widely viewed as an intervention for preventing lightheadedness when moving from seated to standing positions.

However, contrary to this recommendation, researchers at Beth Israel Deaconess Medical Center (BIDMC) found that higher sodium intake, when studied in the context of the DASH-Sodium trial (Dietary Approaches to Stop Hypertension), actually increases lightheadedness. These findings challenge traditional recommendations to increase sodium intake to prevent lightheadedness. The study appeared today in the Journal of Clinical Hypertension.

"Our study has real clinical and research implications," said Stephen Juraschek, MD, PhD, the study's corresponding author and a primary care physician at BIDMC. "Our results serve to caution health practitioners against recommending increased sodium intake as a universal treatment for lightheadedness. Additionally, our results demonstrate the need for additional research to understand the role of sodium, and more broadly of diet, on lightheadedness."

The researchers used data from the completed DASH-Sodium trial, a randomized crossover study that looked at the effects of three different sodium levels (1500, 2300, and 3300 mg/d) on blood pressure. All participants ate each of the three sodium levels in random order for four weeks. Half of the participants ate the sodium levels in the context of a typical American diet (a control diet) while the other half ate the sodium levels consistent with DASH diet guidelines. The original trial showed that by lowering sodium, blood pressure was also lowered - and was the basis for current guidelines for sodium consumption. The study also asked people to rate their experience of lightheadedness when they stood up, although these data were never reported. As such, in this secondary analysis of the DASH-Sodium trial, the researchers examined the impact of increased sodium intake on postural lightheadedness.

The study's findings suggest that concerns about reducing sodium causing lightheadedness may not be scientifically based. It also further questions recommendations to use sodium to treat lightheadedness, an intervention that could have negative effects on cardiovascular health.

"Health practitioners initiating sodium interventions for orthostatic symptoms now have some evidence that sodium might actually worsen symptoms," said Juraschek. "Clinicians should check on symptoms after initiation and even question the utility of this approach. More importantly, research is needed to understand the effects of sodium on physical function, particularly in older adults."

The study also examined subgroups of the population, including older adults (age 60 and above) and adults with obesity. The effects of sodium on lightheadedness differed between these groups. In particular, higher sodium increased lightheadedness in younger people, but modestly reduced lightheadedness in older adults.

"Sodium is widespread in our foods, yet its effects are poorly understood," said Juraschek. "This study illustrates the importance of more trials involving the foods we eat so that we can better understand what constitutes a healthy diet."
-end-
In addition to Juraschek, coauthors include Allison W. Peng, BS, Lawrence J. Appel, MD, MPH, Noel T. Mueller, PHD, Olive Tang, AB, and Edgar R. Miller III, MD, PhD - all of The Johns Hopkins University School of Medicine, The Johns Hopkins Bloomberg School of Public Health, and the Welch Center for Prevention, Epidemiology and Clinical Research, Baltimore, Maryland.

This work was supported by the National Heart, Lung, and Blood Institute, Grant/Award Number: U01-HL57173, U01-HL57114, U01-HL57190, U01-HL57139,K08 HL03857-01 and U01-HL57156; General Clinical Research Center Program of the National Center for Research Resources, Grant/Award Number: M01-RR02635 and M01-RR00722; NIH/NHLBI, Grant/Award Number: K23HL135273, R21HL144876 and K01HL141589.

About Beth Israel Deaconess Medical Center

Beth Israel Deaconess Medical Center is a patient care, teaching and research affiliate of Harvard Medical School and consistently ranks as a national leader among independent hospitals in National Institutes of Health funding.

BIDMC is in the community with Beth Israel Deaconess Hospital-Milton, Beth Israel Deaconess Hospital-Needham, Beth Israel Deaconess Hospital-Plymouth, Anna Jaques Hospital, Cambridge Health Alliance, Lawrence General Hospital, Signature Healthcare, Beth Israel Deaconess HealthCare, Community Care Alliance and Atrius Health. BIDMC is also clinically affiliated with the Joslin Diabetes Center and Hebrew Rehabilitation Center and is a research partner of Dana-Farber/Harvard Cancer Center and the Jackson Laboratory. BIDMC is the official hospital of the Boston Red Sox. For more information, visit http://www.bidmc.org.

Beth Israel Deaconess Medical Center

Related Blood Pressure Articles:

Brain blood flow sensor discovery could aid treatments for high blood pressure & dementia
A study led by researchers at UCL has discovered the mechanism that allows the brain to monitor its own blood supply, a finding in rats which may help to find new treatments for human conditions including hypertension (high blood pressure) and dementia.
Here's something that will raise your blood pressure
The apelin receptor (APJ) has been presumed to play an important role in the contraction of blood vessels involved in blood pressure regulation.
New strategy for treating high blood pressure
The key to treating blood pressure might lie in people who are 'resistant' to developing high blood pressure even when they eat high salt diets, shows new research published today in Experimental Physiology.
Arm cuff blood pressure measurements may fall short for predicting heart disease risk in some people with resistant high blood pressure
A measurement of central blood pressure in people with difficult-to-treat high blood pressure could help reduce risk of heart disease better than traditional arm cuff readings for some patients, according to preliminary research presented at the American Heart Association's Hypertension 2019 Scientific Sessions.
Heating pads may lower blood pressure in people with high blood pressure when lying down
In people with supine hypertension due to autonomic failure, a condition that increases blood pressure when lying down, overnight heat therapy significantly decreased systolic blood pressure compared to a placebo.
The Lancet Neurology: High blood pressure and rising blood pressure between ages 36-53 are associated with smaller brain volume and white matter lesions in later years
A study of the world's oldest, continuously-studied birth cohort tracked blood pressure from early adulthood through to late life and explored its influence on brain pathologies detected using brain scanning in their early 70s.
Blood pressure control is beneficial, is it not?
Until recently, physicians had generally assumed that older adults benefit from keeping their blood pressure below 140/90 mmHg.
The 'blue' in blueberries can help lower blood pressure
A new study published in the Journal of Gerontology Series A has found that eating 200g of blueberries every day for a month can lead to an improvement in blood vessel function and a decrease in systolic blood pressure in healthy people.
How to classify high blood pressure in pregnancy?
The American Heart Association (AHA) and the American College of Cardiology (ACC) changed their guidance to lower the threshold criteria for hypertension in adults.
Discovery could advance blood pressure treatments
A team of Vanderbilt University Medical Center researchers, working with the US Department of Veteran's Affairs (VA), has discovered genetic associations with blood pressure that could guide future treatments for patients with hypertension.
More Blood Pressure News and Blood Pressure Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.