Ion-exchange water softeners do not help eczema

January 01, 0001

Ion-exchange water softeners do not help eczema

Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. The researchers from the UK sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children. This was an observer- blind randomised trial involving 336 children (aged 6 months to 16 years) with moderate/severe atopic eczema. All lived in hard water areas (greater than or equal to 200 mg/l calcium carbonate). Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care, or usual eczema care alone.

Eczema severity improved for both groups during the trial. The mean change in SASSAD at 12 weeks was -5.0 (20% improvement) for the water softener group and -5.7 (22% improvement) for the usual care group (mean difference 0.66, not significant). No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors.

The researchers concluded: "Water softeners provided no additional benefit to usual care in this study population. Small but statistically significant differences were found in some secondary outcomes as reported by parents, but it is likely that such improvements were the result of response bias, since participants were aware of their treatment allocation."

This may save parents a lot of money. It is unfortunate that the parents were not blinded re study group.

For the full abstract, click here.

PLoS Med 8(2):e1000395
© 2011 Crown Copyright
A Randomised Controlled Trial of Ion-Exchange Water Softeners for the Treatment of Eczema in Children. Kim Thomas, Tara Dean, Caroline O'Leary et al for the SWET Trial Team. Correspondence to Kim Thomas: Kim Thomas

Category: S. Skin Keywords: ion-exchange, water softeners, treatment, eczema, children, observer-blind randomised trial, journal watch.
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 4 March 2011

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