Water softeners not found to improve childhood eczema
News release from NETSCC, HTA
16 February 2011
The first study of its kind in the world – involving 336 children aged between six months and 16 years old - has shown that installing a water softener for three months brings no additional relief for eczema sufferers.
Up to one fifth of all children of school age have eczema, along with about one in twelve of the adult population. Anecdotal reports from patients and population surveys have suggested a possible link between atopic eczema prevalence and the degree of water hardness.
It had been hoped that water softeners would provide simple but effective relief for children who suffer from this itchy and uncomfortable condition. However, the trial, Softened Water Eczema Trial (SWET) funded by the NIHR HTA programme, showed no objective difference in outcomes between the children whose homes were fitted with water softeners and those without.
The independent trial was run by a team from the Centre of Evidence Based Dermatology at the University of Nottingham with involvement from experts in the water industry. The study recruited children and families living in hard water areas in Nottingham, Cambridge, London, the Isle of Wight, Portsmouth, Leicester and Lincoln.
Chief Investigator Hywel Williams said: “Although the outcome is disappointing in terms of future treatment options for children with eczema, the outcome of the trial is very clear. Despite this, some parents still believed that water softeners were helpful in eczema, and it is important to realise that other benefits of water softening in the home might be important for families too.
“However, both the water softening and control groups improved equally in the study when the eczema was measured objectively, possibly due to extra attention to the child’s condition during the research, such as regular visits from the nurse, keeping a daily symptom diary and having to weigh their regular medication that patients continued to use during the 12 weeks.”
Participants were randomised by a computer into two groups, those whose families had a water softener installed and those who did not. Those who did not have the water softener were then given a softener to try at the end of the study.
The results surprised even the experts. Professor Williams said: “Our research had already shown that eczema is more common in primary school children living in hard water areas in the UK compared with children living in soft water areas. No one really knows why, but it could be because hard water contains high levels of calcium and magnesium, leading to increased use of soaps which can act as skin irritants.”
The water softener industry (through their representative body, the UK Water Treatment Association) – was closely involved in the providing expertise on technical aspects of water softening during the trial and a generic water softener has been specially produced for the study. The industry is met the cost of producing and installing water softener units. However, the study findings are independent from any industry influence.
Tony Frost, Technical Director of the UK Water Treatment Association (UKWTA), said: “We are proud to have been associated with, and contributed towards this trial. The conclusions from the trial are sound and clear but the UKWTA was naturally disappointed with the outcome. Conventionally, water softeners are installed to prevent scale in water heating systems, and scum deposits on sinks and sanitary-ware but for many years, we have received, and continue to receive, reports from purchasers of water softeners that family member’s eczema has improved since its installation. At the end of each participant’s trial period, they were given the option to purchase the softener at cost price; expectations were that uptake would not be significant but 66 per cent of the home-owners opted to purchase. This was surprisingly high bearing in mind the socio-economic spread of the trial population. Unsolicited comments from trial participants on purchase ranged from “it has not affected our child’s eczema but we love the other benefits of softened water” to “our child’s eczema is completely cured – it has transformed our lives”
Trial results are now available in Health Technology Assessment, 2011; Vol.15:08 and have also published in PLOS Medicine 8(2): e1000395.
Notes for editors
1. The National Institute for Health Research Health Technology Assessment (NIHR HTA) Programme funds research about the effectiveness, costs, and broader impact of health technologies for those who use, manage and provide care in the NHS. It is the largest NIHR programme and publishes the results of its research in the Health Technology Assessment journal, with over 600 issues published to date. The journal’s 2011 Impact Factor (4.255) ranked it in the top 10% of medical and health-related journals. All issues are available for download, free of charge, from the website. The HTA Programme is funded by the NIHR, with contributions from the CSO in Scotland, NISCHR in Wales, and the HSC R&D Division, Public Health Agency in Northern Ireland. www.hta.ac.uk.
2. The National Institute for Health Research (NIHR) is funded by the Department of Health to improve the health and wealth of the nation through research. Since its establishment in April 2006, the NIHR has transformed research in the NHS. It has increased the volume of applied health research for the benefit of patients and the public, driven faster translation of basic science discoveries into tangible benefits for patients and the economy, and developed and supported the people who conduct and contribute to applied health research. The NIHR plays a key role in the Government’s strategy for economic growth, attracting investment by the life-sciences industries through its world-class infrastructure for health research. Together, the NIHR people, programmes, centres of excellence and systems represent the most integrated health research system in the world. For further information, visit the NIHR website (www.nihr.ac.uk).
Paul Davey, Programme Manager (Communications)
Telephone: 02380 595 4309, Email: P.A.Davey@southampton.ac.uk