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Do inhaled corticosteroids reduce growth in children with persistent asthma?

Review question: We reviewed the evidence on whether inhaled corticosteroids (ICS) could affect growth in children with persistent asthma, that is, a more severe asthma that requires regular use of medications for control of symptoms.

Background: Treatment guidelines for asthma recommend ICS as first-line therapy for children with persistent asthma. Although ICS treatment is generally considered safe in children, parents and physicians always remain concerned about the potential negative effect of ICS on growth.

Search date: We searched trials published until January 2014.

Study characteristics: We included in this review trials comparing daily use of corticosteroids, delivered by any type of inhalation device for at least three months, versus placebo or non-steroidal drugs in children up to 18 years of age with persistent asthma.

Key results: Twenty-five trials involving 8471 children with mild to moderate persistent asthma (5128 treated with ICS and 3343 treated with placebo or non-steroidal drugs) were included in this review. Eighty percent of these trials were conducted in more than two different centres and were called multi-centre studies; five were international multi-centre studies conducted in high-income and low-income countries across Africa, Asia-Pacifica, Europe and the Americas. Sixty-eight percent were financially supported by pharmaceutical companies.

Meta-analysis (a statistical technique that combines the results of several studies and provides a high level of evidence) suggests that children treated daily with ICS may grow approximately half a centimeter per year less than those not treated with these medications during the first year of treatment. The magnitude of ICS-related growth reduction may depend on the type of drug. Growth reduction seems to be maximal during the first year of therapy and less pronounced in subsequent years of treatment. Evidence provided by this review allows us to conclude that daily use of ICS can cause a small reduction in height in children up to 18 years of age with persistent asthma; this effect seems minor compared with the known benefit of these medications for asthma control.

Quality of evidence: Eleven of 25 trials did not report how they guaranteed that participants had an equal chance of receiving ICS or placebo or non-steroidal drugs. All but six trials did not report how researchers were kept unaware of the treatment assignment list. However, this methodological limitation may not significantly affect the quality of evidence because the results remained almost unchanged when we excluded these trials from the analysis.

Citation: Zhang L, Prietsch SOM, Ducharme FM. Inhaled corticosteroids in children with persistent asthma: effects on growth. Cochrane Database of Systematic Reviews 2014, Issue 7. Art. No.: CD009471. DOI: 10.1002/14651858.CD009471.pub2

Powered/electric toothbrushes compared to manual toothbrushes for maintaining oral health

Manual vs. Electric toothbrushes | Manual toothbrush| Electric toothbrush Review question
This review has been conducted to assess the effects of using a powered (or 'electric') toothbrush compared with using a manual toothbrush for maintaining oral health.

Good oral hygiene, through the removal of plaque (a sticky film containing bacteria) by effective toothbrushing has an important role in the prevention of gum disease and tooth decay. Dental plaque is the primary cause of gingivitis (gum inflammation) and is implicated in the progression to periodontitis, a more serious form of gum disease that affects the tissues that support the teeth. The build up of plaque can also lead to tooth decay. Both gum disease and tooth decay are the primary reasons for tooth loss.

There are numerous different types of powered toothbrushes available to the public, ranging in price and mode of action. Different powered toothbrushes work in different ways (such as moving from side to side or in a circular motion). Powered toothbrushes also vary drastically in price. It is important to know whether powered toothbrushes are more effective at removing plaque than manual toothbrushes, and whether their use reduces the inflammation of the gums (gingivitis) and prevents or slows the progression of periodontitis.

Study characteristics
Authors from the Cochrane Oral Health Group carried out this review of existing studies and the evidence is current up to 23 January 2014. It includes 56 studies published from 1964 to 2011 in which 5068 participants were randomised to receive either a powered toothbrush or a manual toothbrush. Majority of the studies included adults, and over 50% of the studies used a type of powered toothbrush that had a rotation oscillation mode of action (where the brush head rotates in one direction and then the other).

Key results
The evidence produced shows benefits in using a powered toothbrush when compared with a manual toothbrush. There was an 11% reduction in plaque at one to three months of use, and a 21% reduction in plaque when assessed after three months of use. For gingivitis, there was a 6% reduction at one to three months of use and an 11% reduction when assessed after three months of use. The benefits of this for long-term dental health are unclear.

Few studies reported on side effects; any reported side effects were localised and only temporary.

Quality of the evidence
The evidence relating to plaque and gingivitis was considered to be of moderate quality.

Citation: Yaacob M, Worthington HV, Deacon SA, Deery C, Walmsley AD, Robinson PG, Glenny AM. Powered versus manual toothbrushing for oral health. Cochrane Database of Systematic Reviews 2014, Issue 6. Art. No.: CD002281. DOI: 10.1002/14651858.CD002281.pub3

Zinc supplementation for preventing death and disease, and for growth, in children aged six months to 12 years of age

Description: Description: question                               
This review investigated the effectiveness of zinc supplementation for preventing illness and mortality, and for promoting growth, in children between six months and 12 years of age.

Zinc is an essential micronutrient and zinc deficiency is an important public health problem in low- and middle-income countries. Zinc deficiency impairs growth and contributes to numerous child deaths per year due to diarrhoea, pneumonia, and malaria. This review aimed to determine if giving children zinc supplements would help prevent child death, disease, and growth deficits.

Study characteristics
We searched a wide range of electronic databases for studies that randomly assigned children aged six months to 12 years to either zinc supplementation or a control group that did not receive zinc. Eighty randomised studies with 205,401 eligible participants were included in this review. The evidence is current to December 2012.

Key results and the quality of the evidence
Giving children zinc supplements might reduce their risk of death in general, and their risk of death due to diarrhoea, lower respiratory tract infection (LRTI), or malaria. The quality of evidence for overall mortality was high, though evidence for other critical outcomes was only moderate. Children given zinc experience less diarrhoeal disease than children not given zinc; however, zinc does not seem to reduce children's risk of respiratory infection or malaria. Zinc supplementation may have a very small effect on growth, but eating more calories would probably have a larger effect for many malnourished children. Children who take zinc supplements may experience vomiting as a side effect.

Citation: Mayo-Wilson E, Junior JA, Imdad A, Dean S, Chan XHS, Chan ES, Jaswal A, Bhutta ZA. Zinc supplementation for preventing mortality, morbidity, and growth failure in children aged 6 months to 12 years of age. Cochrane Database of Systematic Reviews 2014, Issue 5. Art. No.: CD009384. DOI: 10.1002/14651858.CD009384.pub2

Yoga to prevent cardiovascular disease

Vitamin aBackground
Cardiovascular disease (CVD) is a global health burden. Nevertheless, it is thought that the risk of CVD can be lowered by changing a number of risk factors, such as by increasing physical activity and using relaxation to reduce stress, both of which are components of yoga. This review assessed the effectiveness of any type of yoga in healthy adults and those at high risk of CVD.

Study Characteristics
We searched scientific databases for randomised controlled trials (clinical trials where people are allocated at random to one of two or more treatments) looking at the effects of tai chi on adults at high risk of developing CVD. We did not included people who had already had CVD (e.g. heart attacks and strokes). The evidence is current to December 2013.

Key Results
We found 11 trials (800 participants), none of them were large enough or of long enough duration to examine the effects of yoga on decreasing death or non-fatal endpoints.There were variations in the style and duration of yoga and the follow-up of the interventions ranged from three to eight months.The results showed that yoga has favourable effects on diastolic blood pressure, high-density lipoprotein (HDL) cholesterol and triglycerides (a blood lipid), and uncertain effects on low-density lipoprotein (LDL) cholesterol. None of the included trials reported adverse events, the occurrence of type 2 diabetes or costs. Longer-term, high-quality trials are needed in order to determine the effectiveness of yoga for CVD prevention.

Quality of the Evidence
These results should be considered as exploratory and interpreted with caution. This is because the included studies were of short duration, small and at risk of bias (where there was a risk of arriving at the wrong conclusions because of favouritism by the participants or researchers).

Citation: Hartley L, Dyakova M, Holmes J, Clarke A, Lee MS, Ernst E, Rees K. Yoga for the primary prevention of cardiovascular disease. Cochrane Database of Systematic Reviews 2014, Issue 5. Art. No.: CD010072. DOI: 10.1002/14651858.CD010072.pub2

Early (up to seven days) postnatal corticosteroids for preventing chronic lung disease in preterm infants

TreadmillCorticosteroids can reduce lung inflammation in newborns with chronic lung disease, but there are major adverse effects of the drugs. Chronic lung disease is a major problem for newborn babies in neonatal intensive care units. Persistent inflammation of the lungs is the most likely cause. Corticosteroid drugs have been used to either prevent or treat chronic lung disease because of their strong anti-inflammatory effects. This review of trials found that the benefits of giving corticosteroids to infants up to seven days of age may not outweigh the known adverse effects. The beneficial effects were a shorter time on the ventilator and less chronic lung disease, but the adverse effects included high blood pressure, bleeding from the stomach or bowel, perforation of the bowel, an excess of glucose in the bloodstream and an increased risk of cerebral palsy at follow-up. Use of early corticosteroids, especially dexamethasone, to treat or prevent chronic lung disease should be curtailed until more research has been performed.

Citation: Doyle LW, Ehrenkranz RA, Halliday HL. Early (< 8 days) postnatal corticosteroids for preventing chronic lung disease in preterm infants. Cochrane Database of Systematic Reviews 2014, Issue 5. Art. No.: CD001146. DOI: 10.1002/14651858.CD001146.pub4

Kangaroo mother care to reduce morbidity and mortality in low birthweight infants

OptionsKangaroo mother care (KMC) is an effective and safe alternative to conventional neonatal care in low birthweight (LBW) infants mainly in resource-limited countries.

Low birthweight (LBW) (less than 2500 g) is associated with an increased risk of neonatal morbidity and mortality, neurodevelopmental disabilities, and cardiovascular disease at adulthood. Conventional neonatal care of LBW infants is expensive and needs both highly skilled personnel and permanent logistic support. The major component of KMC is skin-to-skin contact (SSC) between a mother and her newborn. The other two components of KMC are frequent and exclusive or nearly exclusive breastfeeding and attempt of early discharge from hospital. Compared with conventional neonatal care, KMC was found to reduce mortality at discharge or 40-41 weeks' postmenstrual age and at latest follow up, severe infection/sepsis, nosocomial infection/sepsis, hypothermia, severe illness, lower respiratory tract disease, and length of hospital stay. Moreover, KMC increased weight, head circumference, and length gain, breastfeeding, mother satisfaction with method of infant care, some measures of maternal-infant attachment, and home environment. There were no differences in neurodevelopmental and neurosensory outcomes at one year of corrected age.

Citation: Conde-Agudelo A, Díaz-Rossello JL. Kangaroo mother care to reduce morbidity and mortality in low birthweight infants. Cochrane Database of Systematic Reviews 2014, Issue 4. Art. No.: CD002771. DOI: 10.1002/14651858.CD002771.pub3

Exercise-based rehabilitation for heart failure

Vitamin DBackground
People with heart failure experience marked reductions in their exercise capacity, which has detrimental effects on their activities of daily living, health-related quality of life and ultimately their hospital admission rate and mortality.

Study characteristics
We searched the scientific literature for randomised controlled trials (experiments in which two or more interventions, possibly including a control intervention or no intervention, are compared by being randomly allocated to participants) looking at the effectiveness of exercise-based treatments compared with no exercise on heart failure in adults over 18 years of age. The inclusion criteria of this updated review were extended to consider not only HF due to reduced ejection fraction (HFREF or 'systolic HF') (ejection fraction is a measure of how well your heart is pumping), but also HF due to preserved ejection fraction (HFPEF or 'diastolic HF'). The search is current to January 2013.

Key results
We found 33 RCTs that included 4740 participants. The findings of this update are consistent with the previous (2010) version of this Cochrane review and show important benefits of exercise-based rehabilitation that include a reduction in the risk of hospital admissions due to HF and improvements in health-related quality of life compared with not undertaking exercise. There was a high level of variation across studies in health-related quality of life outcome. While the majority of evidence was for exercise-based rehabilitation in people with HFREF, this update did identify a broader evidence base that included higher risk (New York Heart Association class IV) and older people, people with HFPEF and more programmes conducted in a home-based setting. We found no evidence to suggest that exercise training programmes cause harm in terms of an increase in the risk of death in either the short or longer term. A small body of economic evidence was identified indicating exercise-based rehabilitation to be cost-effective. Further evidence is needed to understand the effect of exercise training in people with HFPEF better and the costs and effects of exclusively home-based exercise rehabilitation programmes.

Quality of evidence
The general lack of reporting of methods in the included trial reports made it difficult to assess their methodological quality and thereby judge their risk of possible bias.

Citation: Taylor RS, Sagar VA, Davies EJ, Briscoe S, Coats AJS, Dalal H, Lough F, Rees K, Singh S. Exercise-based rehabilitation for heart failure. Cochrane Database of Systematic Reviews 2014, Issue 4. Art. No.: CD003331. DOI: 10.1002/14651858.CD003331.pub4

Healthcare interventions for consumers/public
The Cochrane Collaboration, is a not for profit organisation which produces systematic reviews on the effects of healthcare interventions. These reviews are published in an online database, The Cochrane Library monthly.

What is a systematic review?
A systematic review asks a specific research question about a particular healthcare intervention in a clearly defined group of people with a health condition or problem. These reviews summarise the results of healthcare studies and provides the evidence on the effectiveness of the interventions. Systematic reviews are complex and depend on what clinical trials have been conducted, the quality of the trials and the health outcomes that were measured. The review authors combine the numerical data about the effects of the treatment and the authors assess the benefits and harms for the specific treatment.1

SAMRC staff joins Nelson Mandela Build Week

With the help of various sponsors and the involvement of the local community thousands of volunteers from different walks of life recently dedicated their free time to help build 67 houses in one week in Pelican Park, a promising Western Cape suburb where a need for appropriate, affordable housing has been identified.

During Nelson Mandela Build Week from 14-18 July, the non-governmental organisation (NGO) Habitat for Humanity South Africa (Habitat SA) partnered with the Nelson Mandela Foundation to build at least 67 two-bedroom houses that would ensure that pre-selected beneficiaries and families from the community become home owners. Many of them have been on the waiting list for almost 30 years. In the end, funding for four additional houses was secured.

“If you look at our 25 or even 30 years of waiting, you might have only put sand in the cavity walls so I wouldn’t be able to hear my neighbour sneeze, but you would have helped to make the impossible dream a reality. All this is what you (the volunteers) have made possible for us. You will always have a place in my heart and in each of the other families’ hearts,” one of the beneficiaries said. “Your 67 minutes during Mandela Week was well obtained in doing something for our community. On behalf of the home owners’ association I applaud you for coming here and doing this for us. Our icon (late Nelson Mandela) showed us that through reconciliation we can build a better future,” he added.

The Pelican Park Rate Payers’ Association approached Habitat SA to help empower their community through an integrated housing project. The Pelican Park housing project has developed into one of the largest, integrated development projects in the Western Cape.

Habitat SA is linked to an international NGO that strives to forge partnerships with disadvantaged communities to help with the provision of adequate housing. As part of the partnership, skills workshops are also regularly offered in Pelican Park so that the community can not only sustain the houses, but to assist them and other members of the community to improve their own lives and ensure a better future for them.

On Mandela Day, Western Cape Minister of Human Settlements, Mr Bonginkosi Madikizela visited the construction site, saying that the project would not have been possible without buy-in from the private sector. “By partnering with these generous sponsors, we were able to make sure that some of the most disadvantaged individuals in the country are able to become home owners. Because if you are earning less than R4000 a month it is almost impossible to obtain a home loan from a bank,” he said. The keys to the homes were not handed over to the beneficiaries on 18 July, as some of the houses had not been completed.

Volunteers for the Nelson Mandela Build Week were utilised under the guidance of qualified artisans and some of the tasks they had to fulfil included the mixing of cement (dugha), passing building blocks, plastering and sanding of walls. Among the organisations that were represented as volunteers, was the South African Medical Research Council.

Ms Elize de Kock, from the Burden of Disease Research Unit and champion of the Madiba Day event, has been striving to participate in the build week for a long time and was delighted when it finally paid off. “We’ve wanted to do something like this for a long time and when we were officially accepted as volunteers, I didn’t expect that our opportunity to go and work on-site would actually be on Madiba Day itself. As you know the Build for Madiba Day project is happening over the period of a week. When I heard that we would be building on Madiba Day, I knew that it was meant to be,” she said.

Ms de Kock was accompanied by three of her family members, who collectively formed the SAMRC team of volunteers. Ms Charlene Davids, Ms Rifqah Roomaney, Ms Lenadine Koza and Mr Allen Jefthas were also part of the group.

By Lenadine Koza

For more information about what consumers can and cannot get from systematic reviews, please visit the Cochrane Consumer website.

The South African Cochrane Centre which is part of the Cochrane Collaboration, will publish consumer summaries monthly as listed below. Should you require information for a specific health condition please go to and search for the information you require or alternatively contact


1. Cochrane Consumer Network ( Accessed 17 August 2012

For more information, contact the South African Cochrane Centre on (021) 938 0834 or email
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Last updated:
5 August, 2014
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