Saline drip
Hyponatremia is a far more serious condition than was originally thought. While reviewing some of the standard therapies associated with symptoms, I came across some facts that caused me to do a double take. As anyone who has ever been admitted to hospital for treatment knows, the intravenous saline drip is standard therapy and the fastest way to deliver fluids and medications throughout the body. Normal saline drip is the commonly-used term for a solution of 0.91% salt (sodium chloride). The amount of saline infused depends largely on the particular needs of a patient, but on average is typically between 1.5 and 3 liters a day for an adult. So, in order to maintain an average adult in optimum health during a hospital stay, somewhere between 13.7 – 27.3 grams of salt per day is administered. Of course, that doesn't even include the salt that is consumed along with the food. If the hospital dieticians were able to provide meals that corresponded to the current recommended levels, this would add an additional 6 grams of salt for a total of somewhere between 20 and 33 grams of salt a day. And don't forget, every four hours or so, they come by to check on your blood pressure.
I wonder how hospitals will comply with the salt intakes recommended by the Dietary Guidelines Advisory Committee? After all, the Dietary Guidelines recommend 4 - 6 grams of salt per day, about 1/5 of what is currently administered in hospitals!!
Today's NY Times (free subscription) carries an opinion column by science editor John Tierney, "Salt Wars." It recounts the exchanges between medical experts over the advisability of asking the general population to reduce dietary salt and hits both of the key issues, which are:
- Is salt reduction even possible or is "salt appetite" a hard-wired physiological response by the body to its need for this necessary nutrient?
- If population salt reduction were achieved, would public health be improved?
The most interesting aspect of this debate among medical professionals is that those advocating for population salt reduction want to skip over these two questions. Tierney blows the whistle on them, quoting America's leading salt reductionist, Dr. Larry Appel, conceding that the data a "murky" and that there is no evidence of any change in American salt consumption, up or down, in recent decades. Said Appel: “We just don’t have great data on sodium trends over time. I wish that we did. But I can’t tell you if there’s been an increase or decrease.”
To oblige Dr. Appel, while the data on any putative benefit of salt reduction is clearly all over the map with some studies supporting a benefit but more finding no benefit or even heightened risk, the data on the immutability of salt appetite is rather consistent and compelling -- government policies do not move salt consumption among people eating normal amounts of sodium (the U.S. intake is absolutely dead center among nations around the globe).
Recognizing the volatility of the issue, Tierney invited his readers to comment:
You’re welcome to weigh in on any of these issues, especially the question of what scientists really know about the effects of restricting salt. Should Washington follow New York City’s lead in pressuring food companies to take salt out of their products? Or has New York gone beyond what the evidence warrants, as argued by Elizabeth Whelan of the American Council on Science and Health ?
We have heard a lot in the media lately about salt and health. In fact, there has been an unceasing parade of talking heads and cranks that have emerged from the woodwork to repeat the urban legends on blood pressure and cardiovascular deaths that will result from our continued consumption of salt. The fact that cardiovascular disease death rates have plummeted in the last 30 years seems to be lost on these soothsayers. Another fact they conveniently ignore is that the Mediterranean countries that have such excellent cardiovascular figures eat far more salt than we do here in America and at that countries, which consume the highest levels of salt, such as Japan and Switzerland, also have the longest life expectancies. Oh well, how can actual evidence ever compete with a good scare story?
We're beginning to hear about the importance of reducing salt in the diets of young children. Unfortunately, much of what we hear does not coincide with what is being demonstrated in the medical literature.
In particular I refer to a review paper very recently published in Pediatrics, the Journal of the American Academy of Pediatrics, in November 2009. The article is titled Hyponatremia in Preterm Neonates - Not a Benign Condition . In this paper, authors Michael Moritz and Juan Carlos Ayus state that hyponatremia, or low sodium levels in the neonates pose a significant risk for future childhood development. These risks include reduced neuromotor abilities from infancy through later years as well as impaired growth and mental development. Hyponatremia has also been found to be a significant factor for hearing loss, cerebral palsy, intracranial hemorrhage and increased mortality - all because of low sodium levels in the blood resulting from decreased salt intakes.
Furthermore, the authors quoted research carried out in Israel demonstrating that low sodium levels lead to hyponatremic neonates weighing 30% more than their peers maintained at normal sodium levels and that hyponatremia in infants was predictive of increased salt appetite in adolescence and later years. So, once again, contrary to the urban legend of salt consumption leading to obesity, the evidence is exactly the opposite – it is low salt levels in neonates that lead to obesity.
The authors then went on to stress that the emerging literature also suggests that hyponatremia in adults can have very deleterious effects and may be an independent predictor of mortality in hospital patients, those with community acquired pneumonia, with congestive heart failure and liver disease. Chronic low salt levels produces neurologic impairment that affects both balance and attention deficit conditions in the elderly - effect similar to alcohol ingestion. These data were able to explain why low-salt levels are such an important cause of falls and bone fractures in the elderly. This is clinical evidence, not urban legend.
Nutrition and nutrition-related policy initiatives are not things to be trifled with and it's certainly not anything to be left to in competent activists and minimally-trained physicians parading around as nutritionist-wannabes. Neither should they be matters of gratuitous opinion. Nutrition is a key to health and any policies regarding nutrition have to be based upon strong, clinical evidence.
The USDA's Supplemental Program for Women, Infants and Children or WIC program provides food and nutritional information to low-income people who are at nutritional risk - yet, to qualify for the program, WIC foods must contain little or no added salt . Just look at the regulatory requirements for WIC-eligible foods. In particular, there is great concern over products such as vegetables and instant preparations containing vegetables that are required to be made without salt. Not only does this increase the chances for hyponatremia, but because children are so sensitive to the natural bitterness in vegetables, it is unlikely that they will eat them without the addition of salt, thereby robbing of the natural goodness these products contain.
Here again, falling victim to anti-salt propaganda, government bureaucrats in charge of this program have backed away from their responsibilities and blindly gone along with the urban legends and myth-information regarding salt, rather than heeding the published evidence in the medical literature.
As a result, the low income women, infants and children, who are most at nutritional risk have had these risks compounded by the additional risks related to low salt intakes and hyponatremia - risks leading to poor neuromotor development, impaired growth and mental development, hearing loss, cerebral palsy, brain hemorrhage and increased mortality – now how's that for government assistance?
Click the image to see the Vlog or check out the full SaltGuru video .
Water softeners virtually eliminate energy-wasting, service life-shortening scale accumulation on gas and electric water heaters, according to a new study by Battelle Memorial Institute on "Benefits of removal of water hardness (calcium and magnesium ions) from a water supply." Testing electric water heaters over an equivalent 15 months of service found 64 times more scaling on unsoftened water than softened water (14 grams/year softened versus 907 g/yr for unsoftened). For gas water heaters, the scale reduction was even more dramatic. Over more than two years' equivalent service, heaters fed with unsoftened water accumulated 74 time the amount of scaling as those fed softened water (7 g/yr for softened versus 528 for unsoftened). Instantaneous gas heaters fed unsoftened water declined in thermal efficiency from 80 to 72 and, even when delimed, only recovered 62% of the lost efficiency. The thermal efficiency of all water heaters using softened water was unimpaired.
For gas storage and instantaneous water heaters, the use of a water softener to eliminate or minimize the scale forming compounds in water will result in the efficiency of the water heater remaining constant over the life of the unit. In contrast, gas storage and instantaneous water heaters using unsoftened water had a noticeable decrease in efficiency over the testing period resulting in higher natural gas use.
The increase in total energy consumption (as a result of a reduction in heat transfer efficiency) is related to hardness: higher water hardness will lead to greater energy consumption without the use of water softener, and consequently greater energy costs."
The report calculates the percentage of lifecycle energy cost savings using softeners ranging from 3.1% for "moderately hard" water with 5 grains hardness per gallon to 6.6% for "hard" water with 10 grains hardness, 14.5% for "very hard" water with 20 grains hardness and 24.2% for water with 30 grains hardness.
Yesterday's mail brought an imaginative marketing packet from the Ritz-Carlton Amelia Island (near Jacksonville, FL) keyed to the theme "Salt." The packet extolled the excellence of the featured restaurant, "Salt," complete with a sampling of the restaurant's red salt from Hawaii, gray salt from France, pink "Himalayan" salt and black salt, again from Hawaii. Completing the packet was a copy of Mark Kurlansky's best-seller Salt: A World History, and a chef's apron emblazoned "Salt." I'll wear it with pride for all my backyard BBQ entertaining.
Kudos to Ritz marketers.
White House chief of staff Rahm Emanuel is notorious for his advice: "don't waste a good crisis." The National Journal (subscription required) recounts how presidents have evolved in their appreciation that blizzards are national emergencies in the magazine's current article "For presidents, snow has become a reliable catastrophe. It used to be something that you just had to live with ."
President Obama has declared a disaster to facilitate a federal bailout of DC area snowfighters. Last year, he was joking about how well Chicago handled snow and ice. Now he lives in Washington, DC and can appreciate that failed snowfighting is no joke. The article continues:
Where snow falls, disaster follows. Legally, that is. Presidents have turned increasingly to disaster designations over the past 60 years, and snow has become an ever-more-popular entry. But they ignored it at first. It wasn't until January 1977 that snow, by itself, made the disaster cut. That was in Buffalo, N.Y. (no winter wimps there).
Carter started something, and since then snow has become a reliable catastrophe. Last year alone, there were 17 disaster declarations linked to severe winter storms.
It used to be something you just had to live with. When Eva Clark of Pittsfield, Mass., sent Grover Cleveland views of her city after the Blizzard of 1888, along with pictures of the same streets in summer, the president replied, helpfully, "The storm must have been severe to have so filled the streets of Pittsfield with snow, but the views in summer show so delightful a change that you will soon be enjoying the pleasures of your shady home."
Even in the face of real disaster, presidents shrugged. After 98 people died when the roof of Washington's Knickerbocker Theater collapsed in 1922, Warren Harding said, "The terrible tragedy, staged in the midst of a great storm, has deeply depressed all of us and left us wondering about the revolving fates."
Fortunately, we don't have to accept that snowfall equals disaster. Ask your local professional snowfighter!
Apparently, we're not the only ones that thinks the Illinois Policy Institute's new study rating Chicago's snowfighting service: See What They're Saying about Ready for the Snow? is important. The IPI posted this page:
2/16/2010
On February 16th, The Illinois Policy Institute released Ready for the Snow? , an in depth report grading Chicago's snow removal efforts. Here is a sample of what others are saying about the report:Associated Press: Chicago Says It Could Have Handled East Coast Storm
An Associated Press story ran in several publications including the Chicago Sun-Times and News Oklahoma , mentions the Institute's snow removal study, in which we give the city of Chicago an 'A' for their snow removal efforts in the wake of a storm that dropped over a foot of snow on the city.
NBC Chicago: Chicago Makes Snow Removal Honor Roll
NBC Chicago references the Institute's comprehensive study on Chicago's snow removal efforts.
The Salt Institute: Judging Snowfighting Performance
The Salt Institute calls the Illinois Policy Institute's work "outstanding advocacy on behalf of winter safety and mobility."
The Huffington Post: Chicago Snow Clearing Grades: 'A' For Main Roads, 'B+' For Side Streets
The Huffington Post discusses our snow report and the improvements in snow removal that it points to from January to February.
WAND-TV: Snow Removal Means Overtime for City Workers
WAND-TV discusses the cost of snow removal and the 'A' rating the city received in our review of their snow removal services.
Chicagoist: Chicago to East Coast: Your Snow Removal Sucks
The Chicagoist compares Chicago's snow removal efforts, and the 'A' grade it received in our report, to the removal efforts of east coast cities.
For generations, assessing snowfighter performance was a virtual monopoly for transportation and public works professionals, with "purse-string-holders" looking over their shoulder. The public might be happy ... or not, but for the most part, they tolerated delinquent or poor quality service.
There were exceptions to be sure. Chicago mayor Michael Bilandic's infamous snowfighting glitch that ended his electoral career is only the most prominent example. Highway users, roadway safety groups and taxpayer advocates, however, were generally patient as crews struggled heroically to clear away ice and snow.
That may be changing. Media headlines in the hard-hit DC area have included: "Snow paralysis has cost too much " and "Mayor Fenty fails the snow test ."
DC isn't the only place it's snowed, however. Today, the Illinois Policy Institute released a report assessing snowfighting effectiveness in Chicago; it is entitled "Ready for the Snow? Gauging Illinois’s performance on a critical core service ." After recounting the Bilandic episode, the report continues:
People expect clear roads during wintertime – and they want the roads cleared in a timely fashion. If government fails to meet expectations, it does not go unnoticed. In the winter of 2008-2009, Chicago cut overtime services, leaving side roads iced over for days.
Chicagoans were not happy. For the 2009-2010 winter season, Mayor Richard Daley outlined plans to avoid previous mistakes and has committed to keeping the roads safe and clear. Chicago’s Street and Sanitation Department’s 2009 personnel budget for snow removal is $6 million.
The Illlinois Policy Institute report makes a strong defense of snowfighting investments and quotes approvingly from agencies around the state with high levels of winter road maintenance service.
Budgeting for snow removal sits near the top of the priority list for local governments around Illinois; Sangamon County Highway Engineer Tim Zahrn noted, “That’s the first thing we budget for; that’s our primary responsibility.” Officials in the state capital city of Springfield say they “will deploy whatever resources are needed on a storm-by-storm basis.”
IPI calls for new performance standards for snow and ice control operations.It’s no secret snow causes car accidents.
According to the Federal Highway Administration, every year the following occurs:
- 24 percent of weather-related vehicle crashes occur on snowy, slushy or icy pavement.
- 15 percent of weather-related vehicle crashes happen during snowfall or sleet.
- Over 1,300 people are killed and more than 116,800 people are injured in vehicle crashes on snowy, slushy or icy pavement.
Budgeting for road clearing during winter season is a top priority and major budget item for state and local government. Preparation is key for combating winter storms, and once the storm arrives, local and state governments need to hold themselves accountable by implementing snow removal performance standards. In order to measure snow removal standards, state and local governments can set up a metric system to gauge good or poor performance.
And the metric it endorses is truly cast in terms of delivering service on winter roads for roadway users.
- How well was snow removal and salting maintained during the snowstorm?
- How many accidents occurred because of weather conditions?
- How was travel time affected because of the snow?
- At which point were main and side roads clear after the snowstorm stopped?
These are the very questions that snowfighting managers have been grappling with for years. It's nice to see the public paying more attention to its snowfighting investment -- usually the largest single roadway operating budget item for a snowbelt road agency.
Congratulations to the Illinois Policy Institute for its outstanding advocacy on behalf of winter safety and mobility.
With the record-setting snowfall in the DC area this winter, hard on the heels of the embarrassment of ClimateGate, global warming proponents have been rather defensive of late. Among the most outspoken evangelicals has been Robert F. Kennedy, Jr., a lawyer associated with the Natural Resources Defense Council.
A Washington Examiner story recently quoted liberally from Kennedy's global warming warnings during the 2008 presidential campaign. Kennedy wrote an op ed in the LA Times concerning his long acquaintance with weather in the nation's capital:
Snow is so scarce today that most Virginia children probably don't own a sled. But neighbors came to our home at Hickory Hill nearly every winter weekend to ride saucers and Flexible Flyers.
In those days, I recall my uncle, President Kennedy, standing erect as he rode a toboggan in his top coat, never faltering until he slid into the boxwood at the bottom of the hill. Once, my father, Atty. Gen. Robert Kennedy, brought a delegation of visiting Eskimos home from the Justice Department for lunch at our house. They spent the afternoon building a great igloo in the deep snow in our backyard. My brothers and sisters played in the structure for several weeks before it began to melt. On weekend afternoons, we commonly joined hundreds of Georgetown residents for ice skating on Washington's C&O Canal, which these days rarely freezes enough to safely skate.
Meanwhile, Exxon Mobil and its carbon cronies continue to pour money into think tanks whose purpose is to deceive the American public into believing that global warming is a fantasy.
With more than four feet of non-fantasized snow on the ground, igloos in many yards, skaters on the Georgetown canal and myriad sleds and toboggans miraculously appearing, you'd think Kennedy would be embarrassed. Don't bet on it. This is the say guy who argued that a proposed saltworks at San Ignacio lagoon on the Pacific coast of Mexico's Baja would remove so much salt from the ocean that newborn whale calves would find insufficient buoyancy to float and would perish. Underlining the importance of educating the public about salt production, his specious appeal raised more than $100 million, some of which was used to bludgeon proposers of the new saltworks. Truthful, no. But without apology or shame.
Analyses of the economic devastation of snowfalls that paralyze roadway systems confirm the value of effective snowfighting -- and its cost-effectiveness. HIstorical studies were reinforced with the record snowfalls that hit the DC metro area last week. A Wells Fargo analyst told the Wall Street Journal's Marketwatch :
Some spending increased because of the storms. More money was spent to remove snow, and to repair structures damaged by the ice and snow. Sales of snow shovels and parkas increased. Snow can be a stimulus.
On the other hand, some activity was lost forever. "The losses are real," said Mark Vitner, an economist for Wells Fargo Securities. People who were snowed in won't buy an extra lunch when they get back to work, and they won't park their car twice.
Winter storms are more disruptive than damaging.
"The February numbers are going to be a mess," Vitner said. "It's a downer, but how much of a downer, we don't know." Employment, hours worked, wages and retail sales could decline sharply in February, only to rebound in March, if history is any guide. That movement will mostly reflect the timing of the snapshots of economic activity, and not a fundamental shift in the economy's direction.
And a Deutsche Bank economist added:
Economist Joe LaVorgna of Deutsche Bank figures a snow storm in the survey week lowers payrolls by an average of 90,000 compared with the trend line.
For instance, payrolls fell by a seasonally adjusted 51,000 in March 1993 when the "storm of the century" lashed the Midwest and East during the survey week. Employment was strong before and after the storm. In February before the storm, payrolls had risen by 309,000; in April, payrolls rose by 250,000. The average workweek fell by 0.6% in March.
The 1993 storm also had an impact on seasonally adjusted retail sales, which sank 0.7% in March, only to rise 2.2% in April. Housing starts were also bruised by the 1993 storm, falling more than 10% in March and rising more than 16% in April.
During the blizzard of 1996, payrolls fell by 19,000 in January, and then rebounded by 434,000 in February. Average hours fell by 1.2%, the fourth largest decline on record. The three largest declines in hours worked were also due to severe winter storms.
The UK's Food Standards Agency has made since-disproven claims to have achieved population sodium reduction. This week FSA and the Department of Health rolled out a new National Diet and Nutrition Survey .
The NDNS promises to use 24-hour urine samples (UNaV) to measure population sodium intakes -- the approach advocated by the Salt Institute in place of the dietary recall surveys FSA used to claim an overall sodium reduction. But, surprise, the results apparently didn't confirm the rosy projections of the press office. The report is silent on sodium with the excuse that "results from the urine analysis are not included in the current report as the sample size for year one is too small to report."
Not to worry, scientists have reviewed the data already -- and published an analysis that documents no reduction in sodium intake . So, Britons are safe from their government's mindless meddling -- at least for now. Last Fall, researchers reported in the Journal of the American Society of Nephrology:
UNaV and, thus, dietary sodium intake has varied minimally in the UK over the 25 yr encompassing these surveys. The mean sodium intake over the time period 1984 to 2008 was 150 mmol/d. Second, more than 6300 subjects, many providing multiple samples, are the source of these 24 h UNaV measurements from a variety of regions of the UK and Ireland, and they fall within a relatively narrow range.
Not shown, but assessed by us, was the individually determined mean and range of UNaV for women and men where the gender breakdown was available from the survey. Sodium intake for women was 129. Likewise, male sodium intake, which included a 1982 survey of only men living in London, was constant over the same period, although, as would be expected on a caloric basis, higher than that of women, 169.4. The male and female analyses excluded the three Intersalt sites, as the published data provided only the mean for the combined cohort. This statistical analysis of all available 24 h UNaV from the UK does not support recent FSA pronouncements that their national campaign directed at sodium reduction has achieved a significant reduction in the population.
Perhaps the next NDNS will "find" the urinary data these other scientists have already reported in the peer-reviewed literature.
The Mayor Bloomberg initiative (grandiosly referred to as the National Salt Reduction Program), possibly dreamed up by activist groups and leveraged through cronies at New York's health department and their friends at health commission offices around the country, reminds me of something I wrote some time back when I did the history of “Typhoid Mary.” It concerns the abuse of power exercised by Boards of Health and Health Commissions who feel they can, without fear of repercussion, dispense with civil rights in order to execute policies, even if there is no solid evidence to support them. In doing so, these bureaucrats make the self-indulgent leap from civil servants to civil masters without any permission from those they swore to serve.
The quote I am reminded of was by Dr. Josephine Baker, the person who first managed to take 'Typhoid' Mary Mallon into custody. Everyone else looked at Mary's decades-long illegal detention with a clear conscience after her death in custody. Only Dr. Baker spoke up and soberly stated what Mary, a poor Irish immigrant, was up against.
“Typhoid Mary made me realize for the first time what sweeping powers are vested in Public Health authorities. There is very little that a Board of Health cannot do in the way of interfering with personal and property rights for the supposed protection of the public health. Boards of Health have judicial, legislative and executive powers... There have been many typhoid carriers recognized since her time, but she was the first charted case and for that distinction she paid in a life-long imprisonment.”
We see the same mindless, hob-nail boot trampling going on with salt today. C.S. Lewis once said, "Of all tyrannies, a tyranny exercised for the good of its victims may be the most oppressive... those who torment us for our own good will torment us without end, for they do so with the approval of their own conscience."
A muddle of disingenuous advocates, ambitious civil servants and politicians, operating with manipulated evidence, has chosen salt reduction as their cause célèbre. These make-believe crusaders are infused with thought, “Focus on the journey, not the destination.”
Unfortunately, for the public there is a destination, and it is their freedoms and their health.
The former president of Canada's largest science based regulatory agency, the Canadian Food Inspection Agency, cautioned the public recently: "Don't be fooled. Science is always politicized." Ronald Doering argues in the National Post that we should not expect scientists to put aside their policy biases nor confess using their scientific credentials as participants in the policy arena:
That scientists should dress up their science advice as pure neutral science is understandable. For those with scientific expertise, it makes perfect sense to wage political battles through science because it necessarily confers to scientists a privileged position in political debate.
But, does it? Must we lower our high expectations that scientific experts can give us the "straight scoop" without injecting their personal policy preferences to bias their "scientific findings"? I think we can expect more from scientists. Dumbing down our sensibilities in considering scientific studies would result in substituting our own, non-expert biases and thwart progress in embracing new understandings of the reality of the world around us. Count us pro-science.
What can be said of the charge, then, that scientists have biases and their work can only be considered as a political statement? The scientific method is value-neutral. Every scientific study recognizes that the investigator has a "bias" in that the hypothesis to be tested is proposed because the scientist thinks it may offer explanatory value. It is the method itself that will save science from the bias towards confirming the hypothesis. The key here is to get agreement on the quality standards for performing the study and analyzing the results. Those, like Dr. Doering, so insist that we prioritize our understanding of "how policy is scientized and science is politicized" suggest that there is no consensus on standards of scientific inquiry. That's just plain wrong.
A generation ago, the late Dr. Archie Cochrane at Oxford University confronted this question: that scientists seemed to be reaching differing conclusions from the same body of evidence and he devised procedures that grew into the global "evidence-based medicine" movement currently promoted by his eponymous Cochrane Collaboration .
The critical component of evidence-based science is the rigorous separation of method and data. The method must be set out first and the data then gathered and analyzed using that method. It's the opposite of choosing the analytic method after the data have been examined to "discover" that the post-hoc hypothesis is confirmed.
I'm recently returned from the India-International Salt Summit in India and so my eye caught the news that, in the wake of ClimateGate, India has withdrawn from the International Panel on Climate Change (IPCC). India's environmental minister, Jairam Ramesh, was quoted observing: "There is a fine line between climate science and climate evangelism. I am for climate science."
For more than two decades, back to at least 1988 when the Intersalt Study was published, we've seen the same "theological" threat to science in the salt and health controversy. In fact, the shenanigans of the salt reductionist advocacy groups give theology a bad name. It's just the dogmatic rejection of science showing no general health benefit from salt reduction and even the futility of the public health campaign to alter salt intake levels once they are the the range that 90+% of the world's population ingests (the U.S. is right smack in the middle of this intake range).
So, we stand with Mr. Ramesh: we're for nutrition science and not nutrition evangelism in the salt and health debate.
The debate over salt and health continues to wallow at low levels of evidence: opinion or, at best, only observational outcomes studies (with one exception: a randomized trial showing that heart failure patients put on low salt diets suffered worse outcomes).
As a result, the Salt Institute, Grocery Manufacturers Association and many leading researchers are calling for a controlled trial of the health outcomes of the current policy of promoting salt reduction for everybody.
But while the salt controversy simmers, medical scientists are "moving on," recognizing that even well-designed randomized trials (RCTs) can produce results that can mislead policy decisions. TheHeart.org recently carried Sue Hughes' admonition to insist on "clinically significant" RCTs. Hughes summarizes an article in the February 2 issue of the Journal of the American College of Cardiology by Drs. Sanjay Kaul and George Diamond. That issue of JACC also contains an instructive article by Gregg W. Stone and Stuart J. Pocock on the same subject: the clinical significance of RCTs.
So, while salt reduction advocates want us to turn a blind eye to the conceded fact that six of the eight subgroups in the DASH-Sodium trial had no statistically-significant blood pressure improvement (and those subgroups would represent the overwhelming majority of the general public), the discussion in JACC is that statistical significance is not even enough: the findings also need to make a clinical difference. We read "clinical difference" to mean improved outcomes, not simply plausible theoretical modeling results.
Something public health nutrition policy-makers should consider.
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