Episode 83      23 min 40 sec
Infant sleep interventions, low birth-weight babies

PhD students Anna Price and Liz Westrupp discuss their respective research into interventions for sleep-deprived infants and long-term implications for low-birthweight babies. With science host Dr Shane Huntington.

"Sleep problems double the risk of maternal postnatal depression in the first year of life. " - Anna Price




           



Anna Price
Anna Price

PhD candidate at the School of Behavioural Science and the Murdoch Children's Research Institute. Anna's research focuses long-term outcomes and impacts of infant sleep intervention.

Liz Westrupp
Liz Westrupp

PhD candidate at the School of Behavioural Science and the Murdoch Children's Research Institute. Liz is studying the adult psychiatric outcomes of very low birth weight survivors

Credits

Host: Dr Shane Huntington
Producers: Kelvin Param, Eric van Bemmel, and Shane Huntington
Series Creators: Eric van Bemmel and Kelvin Param
Audio Engineer: Russell Evans
Voiceover: Nerissa Hannink
Theme Music performed by Sergio Ercole. Mr Ercole is represented by the Musicians' Agency, Faculty of Music

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Infant sleep interventions, low birth-weight babies

VOICEOVER
Welcome to Melbourne University Up Close, the research, opinion and analysis podcast from the University of Melbourne, Australia. Up Close is available at upclose.unimelb.edu.au.

SHANE HUNTINGTON
Hello and welcome to Up Close, coming to you from the University of Melbourne, Australia.  I’m Dr Shane Huntington.  Today on Up Close we look at two topics of interest being researched by University of Melbourne PhD students.  We're first joined by Anna Price from the Murdoch Children's Research Institute and the University of Melbourne Australia.  Anna is studying the impacts of sleep patterns in babies aged 7 to 12 months.  Recent research has indicated that significant childhood problems such as obesity and mental health can be linked to sleep deprivation.  A greater understanding of the methods and impact of intervention to improve sleep could substantially enhance child health prospects.  Welcome to Up Close, Anna.

ANNA PRICE
Hi, Shane.  Thanks very much.

SHANE HUNTINGTON
Let's start with these sleep problems; the age range is 7 to 12 months.

ANNA PRICE
Yes.

SHANE HUNTINGTON
How common are they in babies?

ANNA PRICE
Well, in the study that we conducted in Melbourne in 2003 we surveyed mums from the community and we found that almost half reported a problem with their baby's sleep at seven months, so our prevalence was 47 per cent.

SHANE HUNTINGTON
Give us an idea of the sort of problems we're talking about.  Is this sort of them waking once or twice a night, or is it continued sleep difficulties throughout that period?  How is it characterised?

ANNA PRICE
It's actually really determined by the parent.  The main question we asked parents, and the question that most studies ask parents is, is your child's sleep a problem for you, yes or no.  If the parent reports that it is, that usually indicates that it is.  But problems generally are difficulty settling to sleep when they're going to bed and frequent night wakings.  They're the main problems.

SHANE HUNTINGTON
Is the expectation for babies at that age to sort of sleep through or are these problems experienced during the daytime sleeps as well?

ANNA PRICE
I think most of the problems come about nighttime sleep, especially in our society.  We do expect or we do want children to sleep through and parents do want a full night's sleep, especially if they need to go to work, things like that.  The idea of sleeping through the night is really only recommended for children six months and older because earlier than that they're often feeding through the night and we don't think they're necessarily developmentally ready to sleep all the way through.  So it is for that 6 to 12 month period that you start looking at it.

SHANE HUNTINGTON
What causes the sleep problems?  Is there a cause that we're aware of?

ANNA PRICE
We've found that the way to remedy sleep problems is actually changing babies' behavior, so I guess it comes down to babies' sleep habits that are usually the problems with it.  Often babies learn to sleep using external cues like their parents, so they're used to be rocked to sleep by dad or fed by mum or driven round the block by somebody.  So when they wake up in the middle of the night - because we cycle through sleep, so we wake up and we come into consciousness during the night - when they wake up and they're in a different situation than the one they went to sleep in, they're very surprised and they want to get back into the context they're used to, so they'll cry out.  It's like if you or I wake up and our pillow's missing; we need that pillow to get back to sleep.  So babies need that.  By changing their habits and getting them to settle by themselves you can hopefully fix or remedy those problems.

SHANE HUNTINGTON
Anna, is there a link between levels of maternal depression and these sleeping sort of difficulties of children in this age group?

ANNA PRICE
Yes, there's a very strong association between the two.  In fact, sleep problems double the risk of maternal postnatal depression in the first year of life.  So in Australia our general prevalence rate, and worldwide, is around 15 per cent.  In the study that I referred to earlier - the one that was conducted in Melbourne - we found that mothers with sleep problems have a doubling of depression symptoms.

SHANE HUNTINGTON
Anna, let's talk now about intervention.  This is obviously an area where you've worked in great detail.

ANNA PRICE
Yes.

SHANE HUNTINGTON
There are obviously programs around now that address the sleeping problems in infants.  Can you run us through the type of intervention that a parent would go into in order to address a child that is not sleeping - or not getting themselves back to sleep, I guess, is the biggest issue.

ANNA PRICE
Yeah, for sure.  The study that we conducted in Melbourne from 2003 to 2005 was actually run through Maternal and Child Health Nurses.  So this is a free universal service that's offered across Australia and it's for parents of new children aged zero to about five or six years.  There are free scheduled visits with a nurse during that time period, straight after birth, very frequently in that first year and then continuing after that.  So, because this is really designed as a community intervention, the study that we ran recruited through nurses and it provided the intervention through nurses.  So, as part of that program or part of that intervention, parents meet with the nurse and they discuss the problems that they're experiencing and the nurse provides information about normal baby sleep for the parent.  Often that in itself is a real help to know how babies cycle through sleep, what to expect from them, when they can sleep through the night, that sort of thing.  They also develop a sleep management plan with the parent and they offer a variety of different techniques, like the one I mentioned earlier where you leave the baby for increasing intervals of time.  So this is called controlled comforting and it's where you pop the baby down to sleep tired but not asleep and you leave them for two minutes, then four minutes, then six minutes, then eight minutes in the hope that they'll learn to settle themselves to sleep.  Another option is camping out.  It takes a little bit longer and involves the parent sitting with the baby in their room and slowly removing their presence from the room; so rather than being outside the room they'd remove their presence.  Otherwise, the nurse will talk to the parent about the routines they have with their baby before sleep, getting into a good routine.  That covers the range.

SHANE HUNTINGTON
You're list to Melbourne University Up Close.  Today we're speaking with Miss Anna Price about infant sleep deprivation.  Anna, these sound like excellent programs.  How successful are they?

ANNA PRICE
Well, in the study that we conducted here in Victoria, Australia we followed children up from eight months, when they were first offered the program, to 12 months and then 24 months, and we found that the program had effects on sleep and maternal wellbeing all the way through that time.  So at the 12 month follow up, which was four months after they had the program, there was a 30 per cent reduction in sleep problems in the intervention group.  At two years, although the difference in sleep problems wasn't as significant, what was really interesting was that there was a significant reduction in maternal depression in the intervention group, so it was really pushing through all the way to 24 months.

SHANE HUNTINGTON
Now, there are some fantastic positives to these programs.  Are there criticisms as well of this type of intervention in the way children sleep?

ANNA PRICE
That's a very interesting question.  All the research to date has shown that these kinds of techniques are helpful when used with healthy mothers and children, but there is concern around the long term effects of them.  Some health professionals and parents are concerned that these kinds of techniques have adverse long lasting effects on children's emotional development.  There's a gap, actually, between research and popular opinion.  The research would suggest that these techniques are beneficial.  The longest follow up has been to when children are about three or four years old to suggest that it helps mums' maternal wellbeing, children's sleep and it doesn't have any adverse impact on children's behavior or emotion.  But the concern around the techniques has actually come from a different body of research which is to do with trauma and neglect, so children who have extremely negative upbringings can go on to have emotional and behavior problems.  The two sets of research have become associated, so these sleep techniques have become associated with this trauma and neglect research.  Nothing has been done empirically - it hasn't been investigated scientifically, which is why I'm following up children to find out if there are long term effects.  But I think it's because it's such an emotive topic for parents that leaving their child and having to hear them cry makes them feel like they might be damaging their child in some way, so it marks sense to link the two, even though research wouldn't suggest they are connected.

SHANE HUNTINGTON
Now your work specifically, as you said, is looking at a group that's gone this.

ANNA PRICE
Yes.

SHANE HUNTINGTON
I understand they're now about six years old.

ANNA PRICE
Yes, they turned six in June/July 2009.

SHANE HUNTINGTON
What exactly are you looking for in that particular group and what are you honing in on in terms of those sort of longer term effects?

ANNA PRICE
Yes.  So the idea is that if the techniques were to effect children's emotional development they would show up through their mental health, their behavior, their stress, their quality of life; those kind of things.  So we followed up this group of children who were involved in the randomised trial a few years back and we measured all of those outcomes.  So we used psychosocial questionnaires for a lot of the outcomes, parents report on those.  We have measured children's cortisol levels and glycosylated haemoglobin levels as a measure of hopefully chronic stress to see if there is a change in the stress regulation of children when they're younger and if that shows when they're older.

SHANE HUNTINGTON
These are chemicals that are produced in the brain?

ANNA PRICE
Yes, they are.  Cortisol is produced by the hypothalamic pituitary adrenal axis and it can be measured really simply through saliva.

SHANE HUNTINGTON
How do you go about distinguishing within that group the effects of the sleep disturbance intervention from all the other effects in their lives?

ANNA PRICE
It's based on the design of the trial.  So we conducted a randomised control trial, which is the gold standard of assessing causality.  You take a large enough sample so it properly represents the community from which it is drawn, and you randomise them.  So essentially you've got two interchangeable groups that are matched on all those things that could affect the outcome; socioeconomic status, number of children, education, all those kind of things.  They should be matched so that when you offer a program or intervention to one and you follow them up over time, any differences should be due to that intervention.

SHANE HUNTINGTON
Anna, in terms of the outcomes that will be used from your research in coming years, what sort of things will you be looking at there and how will it benefit families in the future?

ANNA PRICE
We're really hoping to be able to give parents a full perspective of the effects of these techniques - the long term implications - just so they can be fully informed when choosing how to manage their baby's sleep in that first year of life.  So, it really is just about being able to answer the questions for those health professionals and the parents and let them choose what's best for their family.

SHANE HUNTINGTON
Anna, we wish you the very best of luck with your research endeavor and thank you very much for being a guest on Up Close today.

ANNA PRICE
Thanks, Shane.

SHANE HUNTINGTON
Our second PhD student today is Miss Liz Westrupp, although from the Murdoch Children's Research Institute and the School of Behavioral Sciences at the University of Melbourne, Australia.  Liz is studying the difficulties experienced by children born with very low birth weight.  In many cases, significant health problems persist for many years but questions about whether these problems continue into adulthood remain unanswered.  Welcome to Up Close, Liz.

LIZ WESTRUPP
Hi.  Thank you for having me.

SHANE HUNTINGTON
Liz, can you give us an idea of what you mean by very low birth weight.

LIZ WESTRUPP
Sure.  So very low birth weight refers to usually a preterm in fact born weighing less than 1500 grams, that's around about three pounds, I think.

SHANE HUNTINGTON
What are some of the causes of this, first of all, early birth that connected to that very low birth weight.

LIZ WESTRUPP
A preterm birth can either be indicated, which means that it's brought on by the medical professionals because they think, you know, for example, the infant's or the mother's life is at risk.  Or, alternatively, it can be a spontaneous preterm birth and there are lots of risk factors for a spontaneous birth.

SHANE HUNTINGTON
Now, can you tell us a bit about the environment for the in fact in terms of the separation that they must be experiencing at that point from the parents?  I'm imaging a scenario where they are separated and they are kept alive by a variety of machines in an isolated scenario.

LIZ WESTRUPP
Sure, that's right.  So the environment that they are having will be quite different from a term or a normal birth weight baby, who will maybe spent one or two nights in hospital and then would usually go home.  So, for a start, there's the social environment which changes.  That includes the amount of the contact that parents, and particularly the mother, can have with their newborn infant.  We know from a lot of research that touch is really important, so if we look at the preterm environment, that has really reduced the amount of touch because they're often incubated.  We're talking really, really small babies, you know, less than the size of the palm of my hand, and they can be linked up often to a lot of machines, and it can be really bright, harsh lights.  If you think that this child is not yet mature and a lot of their organ systems are not yet mature, it's a very harsh environment to be introduced to.

SHANE HUNTINGTON
Liz, let's talk a little bit about the behavioral and psychiatric problems that are experienced by babies that go through this particular experience.  This is the focus of your work.  Where's the link?  What's happening there?

LIZ WESTRUPP
Okay.  There's been a lot of research that's followed infants and children born very low birth weight at various times through childhood and adolescence, and much fewer who have followed them into adulthood.  We know from the childhood and adolescent studies that these children are more at risk of having a number of mental health and behavior problems.  So, for example, research suggests that they are around about two to three times more likely to have externalising behavior problems or attention deficit hyperactivity disorder.  They are also more at risk of a number of other emotional or anxiety problems, which we term internalising disorders.  That could include mood disturbances, such as depression, or anxiety problems, too.

SHANE HUNTINGTON
This is evidenced at very young age, when they're early school sort of age, is it?

LIZ WESTRUPP
Definitely at school age, the internalising research starts there.  But there's evidence that studies looking at children in their toddler years - say two to three years of age - there's fewer studies but some of those suggest that they are more likely to show different temperaments, possibly be a little bit more difficult, hard to manage; so some evidence of behavior problems very early on.

SHANE HUNTINGTON
Liz, is there currently an understanding of what links these psychiatric issues with the very low birth weight conditions that the children are experience?

LIZ WESTRUPP
There are a range of difficult theories that deal with that issue - and we really still are at that point of theorising because we're really not sure - but it's likely to be a range of different things.  When a baby is born really early, as I said before, a lot of their organ systems are not fully matured.  That includes the brain and there's a range of brain complications or brain injury associated with preterm birth.  So that, in itself, can be a huge risk factor for a range of behavioral and psychological problems later down the track.

SHANE HUNTINGTON
We've been talking about children, primarily, but what is the sort of transition into adulthood?  Are these sort of psychiatric difficulties transitioned into adulthood as well?

LIZ WESTRUPP
Lots of the research hasn't been able to follow the very low birth weight survivors prospectively, so that means that most of them have really just seen the very low birth weight, for example, children at one time point.  What my study did which was different was recruit these children and families at birth, and then we've followed them from that time at different time points throughout childhood, adolescence and then into adulthood.

SHANE HUNTINGTON
Is this something you're involved with throughout that entire period, or is it an effort by many researchers?

LIZ WESTRUPP
Look, it's definitely an effort by many researchers.  I've come onboard to look at when this cohort are now adults, but it was begun over 30 years ago - begun in 1977 at the Royal Women's Hospital in Melbourne.  So, to come back to your question, there hasn't been a lot of research that's looked at adulthood outcomes, must less than other research that's looked at childhood and adolescent outcomes, for example.  There is, however, some suggestion that very low birth weight adults continue to show psychological problems or possibly have, you know, slightly different personality traits compared to non‑preterm, normal birth weight adults.

SHANE HUNTINGTON
You're list to Melbourne University Up Close.  I'm Dr Shane Huntington and today we're talking with Liz Westrupp about very low birth weight babies and their outcomes.  Liz, I can imagine part of the reason for lack of data here is that very low birth weight children, in terms of their survival rate 20 or 30 years ago - when we're talking about adults now - were not surviving as much.  Is that true?

LIZ WESTRUPP
That's exactly right.  So there were huge technological changes during the 1990s, but even before that in terms of the kinds of neonatal care that was offered this population.  So, really huge changes have meant that the mortality rate has vastly decreased, however the morbidity rate has probably increased, as you say, because more preterm infants are being kept alive when they otherwise may not have survived.

SHANE HUNTINGTON
Now, clearly, not all very low birth weight children develop these particular problems.  Are there specific sort of indicators or factors that are linked with the ones that do?

LIZ WESTRUPP
That's a fantastic question and that's really what I'm trying to do in my research, it's my particular area of interest.  I think it's really important to note that most preterm or very low birth weight survivors don’t show these kinds of problems.  However, it is an increased risk compared to other non-preterm or normal birth weight populations.  So, for example, in my research I've found in adulthood, that compared to the normal birth weight sample group that I had, of the very low birth weight adults about one-third of them had a psychiatric disorder, whereas only one-fifth of the normal birth weight adults had one.  So, you're right, that still says that around about two-thirds of more of very low birth weight survivors are doing really well.  In terms of predictors of outcome, I think that's a really complex picture.  Where we're at, at the moment, is trying to piece together different kinds of factors.  So there's biological factors which we know are important, and they include the medical complications that can be associated with preterm birth.  That includes brain injury, too.  There are also a number of other social and environmental factors which may or may not be related to being born preterm.  So being born preterm - we sort of talked a little bit about it earlier - can really change the first few months that the baby experiences.  It can all really impact on the attachments that infant and the parent can form, and we know that attachments are really important in terms of forming children and influencing their behavior later.

SHANE HUNTINGTON
How recently have we made this connection between very low birth weight children and children with certain psychiatric problems?

LIZ WESTRUPP
This research has been around for a long time.  It's been probably 20, 30 years that we've been looking at the morbidity of children born very low birth weight.  In terms of psychiatric outcomes, behavior problems have been examined for a long time.   There are a number of other neuropsychological outcomes that we haven't talked about yet which have also been examined over time.  Increasingly, researchers are more interested in looking at what are their cognitive outcomes and also, you know, are there more subtle deficits that these survivors are more at risk of.

SHANE HUNTINGTON
Let's talk about the cognitive outcomes for a moment.  Are there significant differences between this group in the population compared to the normal birth weight children?

LIZ WESTRUPP
Yeah, there are, right across the board.  So in terms of general intelligence, they tend to on average have a slightly lower overall IQ on intelligence measure.  They also are more likely to have other problems such as sustaining attention, some problems with memory, learning problems.

SHANE HUNTINGTON
Related to that, are there mechanisms in place at the moment that allow us to identify these children at points in their life when they're at risk?

LIZ WESTRUPP
That's where the research is heading towards.  I think we've already done a lot and, always, the objective of our research is to develop intervention programs in order to help preterm and very low birth weight infants and children, adults, etc.  There are prevention programs, for example, that intervene very early on in terms of when the family's still in the hospital and they're just leaving, that support the family through that transition and also perhaps provide extra support in terms of parenting strategies, etc.

SHANE HUNTINGTON
Liz, just finally, what are the big questions that you're hoping to answer with this research in the near future?

LIZ WESTRUPP
I would really like to look at what it is that makes it more likely for some survivors of very low birth weight to develop problems and why it is that others are protected or quite resilient during their life, and end up having a positive life.  I'm really interested in what is the combination of biological, social and environmental risk factors at different time points that puts this population most at risk.

SHANE HUNTINGTON
Liz, we wish you the best of luck with your research, it's certainly something dear to many of our hearts, and we thank you very much for being our guest on Up Close today.

LIZ WESTRUPP
Thank you very much.

SHANE HUNTINGTON
Relevant links, a full transcript and more info on this episode can be found at our website at upclose.unimelb.edu.au.  We also invite you to leave your comments or feedback on this or any other episode of Up Close.  Simply click on the ‘add new comment’ link at the bottom of the episode page.  Melbourne University Up Close is brought to you by the Marketing and Communications Division of the University of Melbourne, Australia. Our producers for this episode were Kelvin Param and Eric van Bemmel.  Audio engineering by Russell Evans.  Theme music provided by Sergio Ercole.  Melbourne University Up Close is created by Eric van Bemmel and Kelvin Param.  I’m Dr Shane Huntington.  Until next time, goodbye.

VOICEOVER
You’ve been listening to Up Close.  For more information visit upclose.u-n-i-m-e-l-b.edu.au.  Copyright 2010 University of Melbourne.


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