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Updated: 1 day 18 hours ago

Agave syrup no better than placebo cough remedy

Tue, 2014-10-28 05:00

“Placebo cough treatment benefits children and their parents, study suggests,” The Daily Telegraph reports.

A US study found that children’s reported cough symptoms improved even though they were just given a dummy treatment (placebo).

The study compared the effectiveness of agave nectar (a sweet syrup similar to honey, from the agave plant), placebo (flavoured coloured water) or no treatment for night-time cough in 119 children aged between two and 47 months old. Parents were given surveys to record cough symptoms over two days.

Agave nectar and placebo both provided more relief from cough symptoms than no treatment, but there was no difference in relief between agave nectar and placebo.

It is possible that as parents were assessing their children’s symptoms, this could be an example of the placebo effect. That is, parents who thought they were giving their child some syrup, rather than giving nothing, felt that it helped their child’s symptoms. The placebo effect, where people get better because they expect to get better, may sound unlikely, but it has been well documented for decades.

It is also possible that giving something to swallow – either syrup or plain water – is better than nothing when trying to ease a child’s cough.

The best thing that you can do to help a young child with a cough or cold is to make sure that they stay well hydrated with plenty of warm drinks. Honey shouldn't be given to babies under the age of one, due to the risk of infant botulism.

 

Where did the story come from?

The study was carried out by researchers from Penn State College of Medicine, Pennsylvania, and was funded by an unrestricted grant to the Penn State College of Medicine by Zarbee’s Inc, which makes a number of products, including cough syrups. One of the study’s authors has worked as a paid consultant for Zarbee’s Inc, which represents a potential conflict of interest. However, seeing as the main result of the study was that placebos were as effective as agave syrup in treating coughs, it would appear that the study was free of any commercial interference or influence.

The study was published in the peer-reviewed medical journal JAMA Pediatrics. This article was open access, so can be read for free online.

The research was well covered by The Daily Telegraph, though it should be noted that the research article is published in JAMA Pediatrics rather than JAMA Neurology, as the paper wrongly stated.

While the focus of the news - and indeed the title of the research paper - suggest that scientists were looking at whether placebos work for cough mixture, by definition placebos don’t work (except via the placebo effect). In fact, the researchers were testing whether a new formulation of agave syrup could improve cough symptoms. It didn’t improve symptoms any more than placebo.

 

What kind of research was this?

This was a randomised controlled trial (RCT) that aimed to compare the effectiveness of novel pasteurised agave nectar, compared to placebo or no treatment, on nocturnal cough and sleep difficulty associated with acute cough in infants and toddlers.

Agave nectar is a syrup similar to honey that is produced in Central and South America. Unlike honey, it hasn’t been associated with botulism.

An RCT is the ideal way to compare the effectiveness of different treatments.

 

What did the research involve?

The researchers studied 119 children aged between two and 47 months old, who had a cough for seven days or less and visited their GP. Children had a non-specific cough, meaning it was not thought to be due to any particular disease or condition and most likely due to a viral infection. These types of infections are common in young children, as their immune systems are underdeveloped.

They could have other symptoms of a temperature, runny nose or congestion, but were excluded from the study if they had symptoms suggesting more serious conditions, such as asthma or pneumonia.

Children were also ineligible if they had used any medication or honey to treat their cough within six hours of bedtime on the evening before or on the day of enrolment.

Parents were asked to complete a questionnaire about their child’s symptoms the night before. They were asked to rate between one (not at all) to seven (very often/severe):

  • how often did your child cough last night?
  • how severe was your child’s cough last night?
  • how bothersome was your child’s cough last night?
  • how severe was your child’s stuffy nose last night?
  • how severe was your child’s runny nose last night?
  • how much did last night’s cough affect your child’s ability to sleep?
  • how much did your child’s cough affect your own ability to sleep last night?

The parents of the studied children reported at least “moderately often” or “moderately severe” (a score of four or more) on at least two of three questions related to cough frequency, cough effect on child sleep and cough effect on parent sleep.

The children were randomised to:

  • grape-flavoured pasteurised agave nectar (from Zarbee’s Inc, which funded the study)
  • coloured grape-flavoured water (placebo)
  • no treatment

The children received one of these options 30 minutes before bedtime.

Within 30 minutes of waking, the parents again completed the same questionnaire about their child’s symptoms.

The researchers compared the change in symptoms between nights for the three different groups.

 

What were the basic results?

Within each study group, symptoms significantly improved from baseline.

When treatment-night effects of agave nectar, placebo and no treatment were compared, agave syrup and placebo were both superior to no treatment for all symptoms apart from how bothersome the cough was.

However, there were no significant differences in any outcome when agave syrup was compared to placebo.

 

How did the researchers interpret the results?

The researchers concluded that “in a comparison of agave nectar, placebo and no treatment, a placebo effect was demonstrated, with no additional benefit offered by agave nectar. Health care professionals should consider the potential benefits and costs when recommending a treatment with only a placebo effect for infants and toddlers with non-specific acute cough.”

 

Conclusion

This RCT compared the efficacy of agave nectar, placebo or no treatment for night-time cough in children aged between two and 47 months old.

Agave nectar and placebo both provided more relief from cough symptoms than no treatment, but there was no difference in relief between agave nectar and placebo.

It's possible that as parents were assessing their children’s symptoms, this study could be an example of the placebo effect. That is, parents who thought that they were giving their child some syrup, rather than giving nothing, felt that it helped their child’s symptoms. Equally, it is possible that giving something to swallow – either syrup or plain water – is better than nothing at helping to ease a child’s cough.

All children included in this study had a cough for less than a week and other cold-like symptoms, such as runny nose or congestion. This is likely due to a viral infection and requires no specific treatment. There is no good evidence that over-the-counter cough medicines actually work against an acute cough. The Medicines Regulatory Agency in the UK currently advises that over-the-counter cough and cold medicines shouldn’t be given to children under six years. Honey also shouldn’t be given to children aged under one.

The best thing you can do to help a young child with a cough or cold is to make sure that they stay well hydrated with plenty of warm drinks.

The study does highlight the remarkable impact the placebo effect can have in certain cases. There are libraries full of evidence showing how symptoms can dramatically improve for a range of conditions, even though a patient was given a sugar pill or a salt water injection. This may suggest that the mind can have a considerable effect on the symptoms of the body in some cases.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Placebo cough treatment benefits children and their parents, study suggests. The Daily Telegraph, October 27 2014

Links To Science

Paul IM, Beiler JS, Vallati JR, et al. Placebo Effect in the Treatment of Acute Cough in Infants and Toddlers - A Randomized Clinical Trial. JAMA Pediatrics. Published online October 27 2014

Categories: News

Drugs may work better at certain times of the day

Tue, 2014-10-28 04:00

“Take your medication at the right time of day or it might not work,” The Independent reports.

The news is based on a study which looked at the pattern of genes made in 12 different mouse organs, to see if any of the genes showed a circadian rhythm (the “body clock”: where the body reacts to a day and night cycle).

Nearly half of genes that code for proteins showed a circadian rhythm in at least one mouse organ. 

In most organs, such as the liver, the researchers noted that the expression (activity) of many genes peaked during “rush hours” before dawn and dusk.

The researchers found that the majority of best-selling drugs, and medicines listed as “essential” by the World Health Organization (WHO), directly target products of rhythmic genes. As some of these drugs remain active for short periods (have short "half-lives"), the time the drug is taken could impact on how well it works.

However, in the wild, mice are primarily nocturnal (mainly active at night), in contrast to people who are diurnal (mainly active during the day), so the genes that are expressed in a circadian rhythm might be different.

Although this study suggests that medication timing could be modified to improve effectiveness, further studies will be required to determine optimal drug timing. 

 

Where did the story come from?

The study was carried out by researchers from the University of Pennsylvania and the University of Missouri, and was funded by the US National Heart, Lung and Blood Institute, and by the Defense Advanced Research Planning Agency (DARPA).

The study was published in the peer-reviewed scientific journal PNAS. This article is open access, meaning that it can be read for free online.

This study was well covered by the UK media. BBC News also featured a useful infographic about the body clock and its impact on biological function.

 

What kind of research was this?

This was an animal study, which aimed to look at the pattern of the genes made in mice over a 24-hour period.

It should be noted that mice in the wild are primarily nocturnal, in contrast to people, who are diurnal, so the genes expressed in a circadian rhythm might be different. Although this study suggests medication timing could be modified to improve effectiveness, further studies will be required to determine optimal drug timing. 

 

What did the research involve?

The researchers looked at the genes that were being made in 12 different mouse organs every two hours over a 48-hour period. The organs that they examined were the:

  • brainstem
  • cerebellum
  • hypothalamus
  • heart
  • aorta
  • kidney
  • adrenal gland
  • liver
  • lung
  • skeletal muscle
  • brown fat
  • white fat

They looked for genes that cycled over a 24-hour (one-day) period.

 

What were the basic results?

The researchers found that 43% of the genes that code for proteins show a circadian rhythm somewhere in the body.

The liver had the most circadian genes, whereas the hypothalamus (part of the brain) had the fewest.

In most organs, the researchers noted that the expression of many oscillating genes peaked during “rush hours”, before dawn and dusk.

The researchers also found that some genes that don’t code for proteins get expressed in a circadian rhythm.

The researchers found that the majority of best-selling drugs, and medicines listed as “essential” by the WHO, directly target products of rhythmic genes. As some of these drugs have short half-lives, the time the drug is taken could impact on how effective they are.

 

How did the researchers interpret the results?

This study found that nearly half of all genes in the mice oscillated with a circadian rhythm somewhere in the body. They go on to say that "a majority of best-selling drugs in the United States target circadian gene products. Many of these drugs have relatively short half-lives, and our data predict which may benefit from timed dosing.”

 

Conclusion

This study looked at the pattern of genes made in 12 different mouse organs, to see if any of the genes showed a circadian, or 24-hour, rhythm.

43% of the genes that code for proteins showed a circadian rhythm in at least one mouse organ. The liver had the most circadian genes, whereas the hypothalamus (part of the brain) had the fewest.

In most organs, the researchers noted that the expression of many oscillating genes peaked during “rush hours” before dawn and dusk.

Although this study suggests that medication timing could be modified to improve effectiveness, further studies will be required to determine optimal drug timing. 

Until further evidence is forthcoming, you should follow the advice that comes with your medication in terms of when to take it.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Take your medication at the right time of day or it might not work, scientists say. The Independent, October 27 2014

Body clock: 'Rush hour' transformation discovered. BBC News, October 28 2014

Drugs may work better depending on time of day. The Daily Telegraph, October 27 2014

Links To Science

Zhang R, Lahens NF, Balance HI, et al. A circadian gene expression atlas in mammals: Implications for biology and medicine. PNAS. Published online October 27 2014

Categories: News