anyone ever hear of buteyko?

synchro

has anyone done it?
does anyone have anything to say bout it?

Snickers Man

Surprised you got no response to this. ACtually there was a thing on TV Three's breakfast show last week about it. Thought there might have been some feedback.

I don't need to do it because I'm not asthmatic. My wife did it a few years ago and swears by it. She has not needed to use Ventolin since.

She is a trained nurse and says that the thinking behind the treatment makes perfect sense. It's all about limiting the amount of air you take in to what you need, as opposed to the broncho dilators like Ventolin which do just the opposite.

It's no miracle cure. You have to work hard at it. But it works for her.

The asthma society won't endorse it. Because they won't invest in research. Because there's no sponsor to pay for it. Because it's a drug-free treatment and there is no bonanza pay off at the end.

If you're asthmatic give it a go. It will probably help you enormously and save you a fortune.

synchro

iv tried it since snickers and its amazing
i put in 110% effort
off my ventolin since
incredible
and its not just my asthma tat has disspeared also my hayfever and daily faitgue among other things
seriously i really think it is a miracle cure!

Snickers Man wrote:

Surprised you got no response to this. ACtually there was a thing on TV Three's breakfast show last week about it. Thought there might have been some feedback.

I don't need to do it because I'm not asthmatic. My wife did it a few years ago and swears by it. She has not needed to use Ventolin since.

She is a trained nurse and says that the thinking behind the treatment makes perfect sense. It's all about limiting the amount of air you take in to what you need, as opposed to the broncho dilators like Ventolin which do just the opposite.

It's no miracle cure. You have to work hard at it. But it works for her.

The asthma society won't endorse it. Because they won't invest in research. Because there's no sponsor to pay for it. Because it's a drug-free treatment and there is no bonanza pay off at the end.

If you're asthmatic give it a go. It will probably help you enormously and save you a fortune.

EamonnKeane

More on it here:
http://en.wikipedia.org/wiki/Buteyko_method

DrIndy

Although I have yet to see any evidence why this dubious and should not occur, neither is there definitive evidence which would make me encourage it actively to patients.

The trend I note however is people with mild asthma seem to notice benefit, the real crunch comes though with people who have moderate to severe asthma who are on long term steroids and/or other agents. I remain doubtful with an open mind.....

BTW - can anyone quote research papers substantiating this as it seems quite interesting.....

synchro

open your mind!

DrIndy wrote:

Although I have yet to see any evidence why this dubious and should not occur, neither is there definitive evidence which would make me encourage it actively to patients.

The trend I note however is people with mild asthma seem to notice benefit, the real crunch comes though with people who have moderate to severe asthma who are on long term steroids and/or other agents. I remain doubtful with an open mind.....

BTW - can anyone quote research papers substantiating this as it seems quite interesting.....

DrIndy

synchro wrote:

open your mind!

Sorry, I cannot - I need evidence of this working effectively first, hence why I ask if anyone knows any research papers to substantiate it. There is unfortunately a lot of quack cures about the place and separating things which have validity from the others is important.

synchro

the best way to find out its effectiveness is to try it for yourself dr nic!

DrIndy wrote:

Sorry, I cannot - I need evidence of this working effectively first, hence why I ask if anyone knows any research papers to substantiate it. There is unfortunately a lot of quack cures about the place and separating things which have validity from the others is important.

DrIndy

Unfortunately, I don't have asthma!

synchro

DrIndy wrote:

Unfortunately, I don't have asthma!

lol
you obviously have read very little about the breathing technique, its claimed to eliminate or dramatically reduce the symptoms of most everyday illnesses
so like i said try it, use yourself as a guinea pig, if it works with you, theres no reason why it wont work on someone else
think of the fuel ro air ration in a stabdard combustion engine -note its importance, now apply tis thought to the human body!

Capt'n Midnight

synchro wrote:

lol
you obviously have read very little about the breathing technique,

Please post an online link to the technique - all I can find are places selling videos and courses (and many of those with qualifications who have endorsed the method seem to be making money in courses or books - not impartial). And warnings about not teaching others unless you have shelled out on a course yourself. It takes years to become a doctor or pharmacist and yet you can find loads of stuff on the internet about self-medication. I won't have an open mind until I can see the techniques used are open, I don't accept that a short training period will suffice for a teacher if the technique is dangerous.

its claimed to eliminate or dramatically reduce the symptoms of most everyday illnesses

politicians make claims like that too. I still haven't heard of anyone promoting alternative medicine respecting the results of a negative trial. In the early days of using Lithium for example psychiatrists did a trial comparing durgs vs. drugs and therapy and they concluded and announced that it that particular case the drugs alone were just as effective.

so like i said try it, use yourself as a guinea pig, if it works with you, theres no reason why it wont work on someone else

not unless everyone has the same physiology.

think of the fuel ro air ration in a stabdard combustion engine -note its importance, now apply tis thought to the human body!

lean burn to fuel rich mixtures are used and some cars are tuned to get 1% CO (carbon monoxide) in the exhaust

Can something this simple affect your health - yes.
Can buteyko improve your health more than other techniques - not enough impartial nformation in the public domain to decide yet.

IIRC breathing into a paper bag is a standard treatment for hyperventilation , by using an increased level of C02 to give feedback - low C02 can also be a problem when you have alkaline scrubbers in enclosed spaces like submarines or spacecraft.

DrIndy

I too would like evidence. As a scientist, I need proof. Unfortunately, personal references to people with whom it is effective is the lowest form of medical evidence, akin unfortunately to blasphemy for doctors. Trials are needed and if any exist, I would sincerely like to peruse them.

synchro

the solution to all major health problems ir literally right under our noses
think about-the importance of breathing
wat about the many cuktures around the world who swaddle their young infant to insure their breathing is shallow during this critical stage in their life?

Wibbs

synchro wrote:

lol
you obviously have read very little about the breathing technique, its claimed to eliminate or dramatically reduce the symptoms of most everyday illnesses

That's the problem right there. If it claimed a benefit with just one condition, I'd be a little less sceptical. Claiming increased benefits for wildly disparate conditions is a common marker for quackery. That said I do find many conditions are over medicated. Especially in the mild cases. As has been pointed out this and other techniques probably work very well in those where the condition has a large mental factor. I know many asthmatics like this. One I know actually had a mild attack when I pretended to light up a ciggie in her presence as she was convinced that tobacco smoke caused attacks. I know another who is convinced that starting to smoke stopped his attacks. Both equally daft.

think of the fuel ro air ration in a stabdard combustion engine -note its importance, now apply tis thought to the human body!

Sadly most of us don't have VTEC lungs. I certainly don't. More like a rattling deisel with all the ciggies In any event based on that analogy you should be forcing more not less O2 into your body as combustion engines work better the more O2 you can force into them. That's what turbos are for. I'm off to slap a supecharger to my head. Dr Indy, can you recommend a surgeon for the procedure...?

Snickers Man

DrIndy wrote:

I too would like evidence. As a scientist, I need proof. Unfortunately, personal references to people with whom it is effective is the lowest form of medical evidence, akin unfortunately to blasphemy for doctors. Trials are needed and if any exist, I would sincerely like to peruse them.

I posted something similar in another thread on the same subject. This is from a piece in the Indo, admittedly something that looks to be an advertorial on behalf of a Buteyko practitioner but it rings true anyway.

According to Dr Pat Manning, chairman of the medical committee of the Asthma Society of Ireland and Consultant Respiratory Physician at the Bon Secours Hospital, Dublin, the research evidence is not to their liking because it is not scientifically rigorous enough. The society has no objection to conducting its own tests, he said, provided someone puts up the hefty cash for the trials, and it will then subject Buteyko to the most thorough scientific testing, a process which he warns could take a very long time. But he has no plans to do so.

So the Irish Asthma Society will do the research if somebody stumps up the cash, but who's going to do that? It's not in the financial interest of any likely interested party to do so. Drugs companies would happily fund research that would result in a recommendation to take a drug that they themselves are manufacturing. There's a clear payoff for them in the end.

But because Buteyko is drug free, there is no payoff in the end, except to Buteyko practitioners and there's not really a lot of money in that. What they do is run courses, typically lasting a weekend which might cost a couple of hundred euro. That's all they would make out of each patient for life. After the course, each patient is on their own.

Measure that against what the typical asthma patient, let alone the tax payer who subsidises the cost, pays on Ventolin in the course of a year never mind a lifetime and it's peanuts.

So here's a question for you, doctor.

Is it not an inherent weakness in our medical system that a phsyiological, exercise based treatment such as this cannot be properly verified because nobody has a vested interest in its adoption? Apart from the sufferers of course.

The practitioners of this method can explain the physiological science underpinning it. Regardless of what synchro says it is NOT a miracle cure in that it takes a sustained, disciplined committed effort to work it through. It is drug free, which has GOT to be inherently better than a drug-based cure to my mind. (Think Vioxx, Thalidomide, and whatever it was that caused Elan's share price to tank earlier this year). And it works. For many people.

So how DO you gain approval for such a treatment?

Capt'n Midnight

Snickers Man wrote:

So the Irish Asthma Society will do the research if somebody stumps up the cash, but who's going to do that? It's not in the financial interest of any likely interested party to do so.
....
But because Buteyko is drug free, there is no payoff in the end, except to Buteyko practitioners and there's not really a lot of money in that. What they do is run courses, typically lasting a weekend which might cost a couple of hundred euro.

How much do trials cost ?

The health service could easily fund it.

However, I disagree with the no payoff in the end bit, since I can't see any free information on the treatment, just self promoting PR blurb. Maybe it's because I'm looking in the wrong places or maybe it's a scam or maybe it's the best thing since sliced bread, but I can't make an informed decision without unbiased information.

Another question - if the method is dangerous so that you can't teach it without doing (and I assume paying for) an instructors course, has anyone had their health damaged by it or spoken out about it or asked for it to be banned ?

jazzbandit

right guys, here's the deal.

I'm sorry to sound crass but.....

For every hippy treatment, you could wheel out a load of ppl who'll say "my granny tried it and her bionic plastic hip is now actually converted back to real bone, and she's doin the long jump for ireland in next year's olympics". These people always want it to be suddenly made free on the national health, and blame a variety of doctors, politicians, drug companies etc when that doesnt happen. The reality is that to test any one treatment takes many years (we've only just got round to rubbishing homeopathy this week, and look how long that's been around) and it would cost a fortune to test every new alternative treatment that gets a mention in a newspaper. The money would be better spent on a variety of different things that we're desperately short of in hospitals, like staff and beds. There's also usually always a suspicious undercurrent about doctors and drug companies being interlinked. Well, the reality is that's rarely thrue. Most docs have no links with drug companies. Most docs will give non-drug treatment before prescribing a drug if that's a reasonable alternative. However, we are ultimatley responsible for that person's health. If a kid comes in during the night with a severe asthma attack and needs to be ventilated because I've given them a breathing DVD instead of an inhaler, my neck is on the choping board, and so is the kid's.
Why dont the people selling these videos conduct their own trilas rather than expecting an over-stretched health service to do their work for them?

when hospitals have extra cash, they try and look at how many people they can cure/improve symptoms with that given amount of money. That usually means a strong evidence base is required with the cost-benefit/cost-effectiveness analysis base being well researched. To my mind, the DVD producers cannot suply this information, making it unethical to spend taxpayers money on it.

The jazz man

Patrick McKeown

I would like to add a number of pointers regarding jazzbandits comments. I am a Buteyko practitioner and have written 3 books on the subject. I am also a former chronic asthmatic who used reversal of hyperventilation very effectively for my own condition which was going from bad to worse.

I am in no doubt that the medical community by ignoring Buteyko have missed a therapeutic intervention for the treatment of asthma. To date two studies investigating BBT for asthma have been published with consistent results of 70% less symptoms, 90% less need for reliever medication and 50% less need for preventer within 3 to 6 months. The most recent study (2003) at Gisbourne hospital New Zealand concluded that BBT is a safe and efficacious asthma management technique with potential pharmo-economic benefits that merit further study. See links to trials from www.buteyko.ie or www.asthmacare.ie

Let’s look at what Buteyko is about. The first part teaches people how to unblock their nose naturally. The second part advocates switching from mouth to nasal breathing and the third part involves the practice of breathing exercises aimed at reducing minute volume.

I was a mouth breather and asthmatic for 25 years and watched my asthma get progressively worse as I continued with this bad habit. Surely it makes common sense for all asthmatics to nasal breathe. A simple breath hold exercise will unblock the nose in minutes with a permanent change being made in days. The nose acts as a natural filter for airborne allergens and serves to warm, and moisten incoming air before being drawn to the lungs.

Buteyko theory rests on the premise that all asthmatics breathe too much. This overbreathing- (while hidden)- may cool, dehydrate the airways or cause a loss of CO2 from the body. (There are different theories as to what is happening.)

For example, if an asthmatic commences physical exercise, or laughs or talks for a period of time - they will generally find that their airways constrict in response to such. All 3 activities cause a larger minute volume thus causing the cooling, dehydrating effect.

On the other hand, swimming results in reduced minute volume due to the face being submerged under water, - airways do not constrict to the same degree as less air has to be conditioned.

The American thoracic society presented a press release in July stating that laughter is now recognised as a greater trigger than dust mites for asthma. The society stated that while they were not sure of the cause, they feel that it may be hyperventilation.

Breathing through the mouth on a regular basis, sighing etc involves hyperventilation. Reversal of this will dramatically improve symptoms.

For four years, I have offered my time at no charge to a number of professional medical bodies in order to determine whether Buteyko is an effective intervention. To date, no one has taken me up on this matter.

Most asthma research if not all is conducted or influenced by drug companies. They have the money, the power and the resources to determine what is researched- whether internal company R&D or hospital or university.

But as long as asthmatics continue to overbreathe – I am certain that they will continue to have asthma.

faceman

Patrick McKeown wrote:

I
Let’s look at what Buteyko is about. The first part teaches people how to unblock their nose naturally. The second part advocates switching from mouth to nasal breathing and the third part involves the practice of breathing exercises aimed at reducing minute volume.

I was a mouth breather and asthmatic for 25 years and watched my asthma get progressively worse as I continued with this bad habit. Surely it makes common sense for all asthmatics to nasal breathe. A simple breath hold exercise will unblock the nose in minutes with a permanent change being made in days. The nose acts as a natural filter for airborne allergens and serves to warm, and moisten incoming air before being drawn to the lungs.

Buteyko theory rests on the premise that all asthmatics breathe too much. This overbreathing- (while hidden)- may cool, dehydrate the airways or cause a loss of CO2 from the body. (There are different theories as to what is happening.)

But as long as asthmatics continue to overbreathe – I am certain that they will continue to have asthma.

Chief, alot of your points are extremely flawed. In fact Im quite shocked at them. I could waffle on but my main point is this - what the hell does asthma have to do with your mouth and nose? Its a lung problem! Im not surprised no one has taken you up on your offer at no charge! I think you have misinterpreted the results from the american thoracic sociarty. Back to the medical books my friend. :-)

Patrick McKeown

faceman wrote:

Chief, alot of your points are extremely flawed. In fact Im quite shocked at them. I could waffle on but my main point is this - what the hell does asthma have to do with your mouth and nose? Its a lung problem! Im not surprised no one has taken you up on your offer at no charge! I think you have misinterpreted the results from the american thoracic sociarty. Back to the medical books my friend. :-)

This is the problem, the medical books say very little about hyperventilation and the effect it has on the human body most notably asthma. Effectively you are saying that it does not matter whether asthmatics mouth or nasal breathe-

NO is manufactured in the nose and acts as a natural bronchodilator, secondly hypocapnia is known to constrict airways (Elshout, 1991, Sterling 1968,) thirdly, overbreathing carries larger quantities of allergens, fourthly, there was a direct correlation in reduction of breathing volume and reduction of symptoms, reliever and preventer medication. (Mater hospital Brisbane, 1995)

In a way it is a pity that more buffoons like you do not have asthma - then you would have the motivation and could determine the results from correction of your own breathing volume.

I will go as far as saying that unless overbreathing is addressed, the problem of asthma will never be solved. People will suffer needlessly and drug companies and those associated with it will be the only winners.

I receive a lot of feedback from people who have read my book, with improvements to quality of life, and reduced need for medication. I have also witnessed a number of children who no longer required hospitalisation from asthma once their breathing was addressed. Each week, I witness tremendous improvements to quality of life and overtime need for medication was reduced.

The New Zealand medical journal concluded that 'BBT is a safe and efficacious asthma management technique with potential pharmo economic benefits that merit further study'. Yes, the paper was unsure how reversal of hyperventilation produced the results it did. It was never the less very positive.


Please don't comment on something that you know absolutely nothing about.

Patrick McKeown

Wibbs

Asthma is a hard one. What has always surprised me is the rates of increase in the last 20/30 yrs. When I was a kid I only knew one kid who had alergies/asthma, now it seems every second person has it. Various reasons are given for the increase, but no real answers. Airborne pollutants are one of them. Weird given that in the past, one could argue that there were more polllutants. More people had pets, carpets, more smoked, more coal smoke in the air etc. The over cleanliness argument seems a good one as asthma seems to be much less prevalent in the third world.

Patrick McKeown, do you have any theories why asthma is so common now? Surely people in the past and in the 3rd world breath in much the same way as today in the west? I say this only to find out why your therapy would work. Given that it would suggest that people have changed their breathing habits.

Reading about this boteyko technique is intriguing. There may be something to it. It certainly should have more clinical trials to see if there are benefits. Anything that can reduce dependancy on drug therapies can only be a good thing.

That said, my own pet theory:) , at least for some asthma sufferers is that it has a large psychosomatic element. They have a one off asthma/breathing problem(possible panic attack), they get diagnosed as asthmatic, get prescribed an inhaler and then become dependant on the psychological comfort it gives them. I can think of at least 3 people who fall into this category. One person I know has an allergy to cat dander which can bring on an asthmatic attack. Once I saw them in a house where unknown to them a cat lived. They were fine until the cat walked in whereupon they started to breath very badly and needed to leave and use their inhaler. All the stranger given that the very armchair they had sat in for over an hour, was the cats favourite sleeping spot. The very sight of the cat had caused an attack whereas the alledged allergen was all around and in contact with them with no symptoms. I realise this does not apply to all asthma sufferers by any means, but I do think the psychological aspect in some cases is sometimes overlooked.

This may explain how this breathing technique works as it would also help with a panic attack, which is psychosomatic.

Pet

I've heard a lot about this technique, a lot of good reports from people I know with asthma, and the thinking behind it makes sense too. But I just don't like the fact that people are charged for learning the technique. It casts a shadow over it, especially for people who know little about it. If it was free, then it would at least be open to proper debate and discussion.

Belfast

I found not using dairy product help mty asthma.
http://www.soil-health.org.nz/pastissues/marapr03/milk.htm

I also when to a chiropracor for a back problem and it imporved my breathing asd well as fixing the pain in my back.

Wibbs

Pet wrote:

But I just don't like the fact that people are charged for learning the technique. It casts a shadow over it, especially for people who know little about it. If it was free, then it would at least be open to proper debate and discussion.

Well doctors and chemists charge for their services and their treatments are open to proper debate and discussion, so if this technique works for some people, I don't see why they shouldn't charge for it.

DrIndy

Patrick McKeown - thanks for providing clinical trials links.

I am having difficulty accessing the first two papers quoted in the website, but can access the third.

There does seem to be promise in this although the trials need to be greatly expanded as the p values are either not statistically significant or barely statistically significant for the results of the mater hospital research cohort.

There is a difficulty however (and this plagues other non-pharmacological therapies such as acupuncture) - and that is the gold standard for clinical evidence is a double blinded placebo controlled trial - and you cannot blind a breathing technique!

There seems to be promise - can you post up more clinical trial links?

Patrick McKeown

Ref: Wibbs-

Asthma increases relative to wealth. This is a known. It does not increase relative to pollution as is more commonly thought. As a nation becomes wealthier, our lifestyles change. We eat more processed food which contain sugars, stimulants etc., we do less physical activity, our houses become warmer, we can be under more stress due to competitive pressures, etc.

All of these factors increase breathing volume which in turn leads to genetically predisposed persons developing asthma.

Some parts of Africa have no asthma and when these people move from the country to the city, asthma rates increase. Likewise, asthma was relatively low in the former Eastern Germany- with unification and adoption of West German lifestyles asthma rates increased. One could arge that better wealth enables better diagnosis but asthma rates have increased so much in the past thirty - fourthy years.

DrIndy- I checked the links on www.buteyko.ie and was able to download trials results. If you wish, I can send you pdf files to your email. My email address is info@asthmacare.ie

Yes, the trials may not have been perfect and the New Zealand trials were not blinded as researchers felt that this was impossible. But it is a start and results overall were positive.

Hopefully, over time, there will be more to follow.

psuedonym

I attended a Buteyko Breathing course about 9 months ago in New Zealand and thought it might be interesting to share my experiences and results.

I have a history of chronic sinus problems. I am a keen amateur athlite and about a year ago I started having problems with weezing and shortness of breath and uncontrollable coughing fits that were only triggered by heavy exercise. The only thing that would relieve coughing fit once it started was ventolin some of these coughing fits lasted many hours. I saw three doctors, my regular MD, an MD that was recommended by a friend who suffers from asthma and finally a breathing disorder lung dysfunction specialist. I was sent to a lung function lab where they stuck me in an airtight chamber and submitted me to salt mist (which incidentally failed to have any detrimental affect on me)and underwent various other tests and scans and was eventually diagnosed loosely with Exercise Induced Asthma, given a prescription for large amounts of preventer and advised to always keep ventolin on hand....and told that my condition was untreatable and I would have to learn to live with the dramatic loss in quality of life.

After this my asthma got progressively worse and I began having regular Asthma attacks in the cooler evenings (when not exercising) and I had to stop training as it was becoming counter productive to my health. In one three month period I was tested (Sophisticated Peak Flow Meter device that graphed the exhalation cycle) after a recent cold and I was told my lung function had halved. The specialist doing the test seemed slightly shocked and doubled my dossage of preventer and put my on a course of prednisone to get things back under control.

Let me say I do not believe in most of alternative medicine but I certainly believe that some of these weird practices have a placebo effect if people believe in them.

In desperation I sought out Buteyko (It had got some good press here in New Zealand -recent clinical trials and also a clinical trial in Australia where they did attempt a blind study where some of the participants were given alternative breathing exercises. I did some research first and even tried to teach myself from a book. While I wouldn't recommend this it gave me enough hope to do a course. I was fairly skeptical (but also desperate).

The training is hard work and does require some commitment and dedication which I found particularly hard as I was also reasonably skeptical (although very hopeful/desperate).

Results have been slow and of the nature of two steps forward and one step backwards. I still seem to be improving each month. However I have now taken no preventer since finishing the Buteyko course ( I was never convinced the Preventer had any positive effect on my Exercise Induced Asthma anyway) and used Ventolin only three times since finishing the course. Previously I was using ventolin several times every day. When I get an attack I practice the Buteyko technique first and on the two occassions this has not got it FULLY undercontrol I have taken Ventolin). I now almost neve have asthma symptoms unless exercising - similar to initial symptoms before things took there downward turn.

I believe that I was over using Ventolin in the past and that this actually aggravated my condition and created a false dependency. This was also well explained on the Buteyko course. Of course this reduction in drugs has saved me a lot of money.

I am now training again but my lung function is still very much reduced Peak Flow typically is 450L/Min down form my pre asthma peek of 600+. (Measured using a Breath -Alert Peak Flow Meter).

As an experiment I used some ventolin tonight (even though I felt pretty good) and my Peak Air Flow increased immediately from 450 to 550 (within two minutes) and went over 600 one hour after taking two puffs.

The Buteyko Breathing Technique has certainly made me more confident in dealing with Asthma attacks. It has had a DRAMATIC improvement on keeping my nasal passages clear of mucous (Which in itself has definitely made the money spent well worth while). Colds and any muscous/nassal blockage always aggravate my Asthma symptoms.

I have begun tentative training again.

I do not believe that Buteyko is an Asthma cure but it has been a very important part of helping me to deal with the symptoms thus far and I feel that I am still improving each month. I have no idea what condition I would now be in if I hadn't done the course and practiced the technique but a recent cold aggravated my condition and gave me a reminder of just how bad things were nine months ago.

My advice try it for yourself, stay open minded. Don't suppress your skepticism and see what results you get.

carryboy

Originally POsted by pseudonym
I do not believe that Buteyko is an Asthma cure but it has been a very important part of helping me to deal with the symptoms thus far and I feel that I am still improving each month. I have no idea what condition I would now be in if I hadn't done the course and practiced the technique but a recent cold aggravated my condition and gave me a reminder of just how bad things were nine months ago.

My advice try it for yourself, stay open minded. Don't suppress your skepticism and see what results you get.

:cool: i agree! you've nothing to lose and much to gain.

Nalz

old thread, but anyone with chronic sinusitis and consistently suffering from chest infections benefited from this?

RobFowl

Zombie thread closed