A Randomised Controlled Trial of Ion-Exchange Water Softeners for the Treatment of Eczema in Children

English version České info

Background:
Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. We sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children.

Methods and Findings:
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 (≥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. The primary outcome was change in eczema severity (Six Area Six Sign Atopic Dermatitis Score, SASSAD) at 12 weeks, measured by research nurses who were blinded to treatment allocation. Analysis was based on the intent-to-treat population. 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, 95% confidence interval −1.37 to 2.69, p = 0.53). No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors.

Conclusions:
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. A detailed report for this trial is also available at http://www.hta.ac.uk.

Trial registration:
Current Controlled Trials ISRCTN71423189

: Please see later in the article for the Editors' Summary

Vyšlo v časopise: A Randomised Controlled Trial of Ion-Exchange Water Softeners for the Treatment of Eczema in Children. PLoS Med 8(2): e32767. doi:10.1371/journal.pmed.1000395
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pmed.1000395

Souhrn

Trial registration:
Current Controlled Trials ISRCTN71423189

: Please see later in the article for the Editors' Summary

Zdroje

1. JohanssonS

BieberT

DahlR

FriedmannP

LockeyR

2004 Revised nomenclature for allergy for global use: Report of the Nomenclature Review Committee of the World Allergy Organization, October 2003. J Allergy Clin Immunol 113

2. SchofieldJ

GrindlayD

WilliamsHC

2009 Skin Conditions in the UK: a Health Care Needs Assessment Nottingham Centre of Evidence Based Dermatology Available: http://www.nottingham.ac.uk/scs/documents/documentsdivisions/documentsdermatology/hcnaskinconditionsuk2009.pdf

3. Lewis-JonesS

2006 Quality of life and childhood atopic dermatitis: the misery of living with childhood eczema. Int J Clin Pract 60 984 992

4. ManciniAJ

KaulbackK

ChamlinSL

2008 The socioeconomic impact of atopic dermatitis in the United States: a systematic review. Pediatr Dermatol 25 1 6

5. EmersonR

WilliamsH

AllenB

2001 What is the cost of atopic dermatitis in preschool children? Br J Dermatol 143 514 522

6. McNallyN

WilliamsH

PhillipsD

Smallman-RaynorM

LewisS

1998 Atopic eczema and domestic water hardness. Lancet 352 527 531

7. MiyakeY

YokoyamaT

YuraA

IkiM

ShimizuT

2004 Ecological association of water hardness with prevalence of childhood atopic dermatitis in a Japanese urban area. Environ Res 94 33 37

8. Arnedo-PenaA

Bellido-BlascoJ

Puig-BarberaJ

Artero-CiveraA

Campos-CruanesJB

2007 [Domestic water hardness and prevalence of atopic eczema in Castellon (Spain) school children]. Salud Publica Mex 49 295 301

9. van den OordRA

SheikhA

2009 Filaggrin gene defects and risk of developing allergic sensitisation and allergic disorders: systematic review and meta-analysis. BMJ 339 b2433

10. TanakaA

TakaiM

YoshinariY

MatsudaH

2009 Ultrapure soft water reduces growth of Staphylococcus aureus adopted on skins of the barrier-disrupted animal model. Allergy 64 1458

11. WilliamsH

2005 Atopic Dermatitis. N Eng J Med 2005;352:2314–24. N Eng J Med 352 2314 2324

12. HoareC

Li Wan PoA

WilliamsH

2000 Systematic review of treatments for atopic eczema. Health Technology Assessment 4

13. ThomasK

SachT

2008 A multicentre randomized controlled trial of ion-exchange water softeners for the treatment of eczema in children: protocol for the Softened Water Eczema Trial (SWET) (ISRCTN: 71423189). Br J Dermatol 159 561 566

14. ThomasK

KollerK

DeanT

GilbertC

SachT

multi-centre randomised controlled trial and economic evaluation of ion-exchange water softeners for the treatment of eczema in children: the Softened Water Eczema Trial (SWET). Health Technology Assessment In press

15. WoodL

EggerM

GluudL

SchulzK

JüniP

2008 Empirical evidence of bias in treatment effect estimates in controlled trials with different interventions and outcomes: meta-epidemiological study. BMJ 336 601 605

16. WilliamsH

BurneyP

HayR

ArcherC

ShipleyM

1994 The UK working party's diagnostic criteria for atopic dermatitis. I. Derivation of a minimum set of discriminators for atopic dermatitis. Br J Dermatol 131 383 396

17. Berth-JonesJ

1996 Six area, six sign atopic dermatitis (SASSAD) severity score: a simple system for monitoring disease activity in atopic dermatitis. Br J Dermatol 135 25 30

18. British Water Code of Practice for the Installation of Ion Exchange Water Softeners. Available: http://www.britishwater.co.uk/publications/Publications_and_Technical_Guides.aspx

19. Water Softeners Available: http://www.ukwta.org/watersofteners.php

20. MeggittS

GrayJ

ReynoldsN

2006 Azathioprine dosed by thiopurine methyltransferase activity for moderate-to-severe atopic eczema: a double-blind, randomised controlled trial. Lancet 367 839 846

21. TakwaleA

TanE

AgarwalS

BarclayG

AhmedI

2003 Efficacy and tolerability of borage oil in adults and children with atopic eczema: randomised, double blind, placebo controlled, parallel group trial. BMJ 327 1358 1359

22. CharmanC

ChambersC

WilliamsH

2003 Measuring Atopic Dermatitis Severity in Randomized Controlled Clinical Trials: What Exactly Are We Measuring? J Invest Dermatol 120 932 941

23. BenjaminK

WaterstonK

RussellM

SchofieldO

DiffeyB

2004 The development of an objective method for measuring scratch in children with atopic dermatitis suitable for clinical use. J Am Acad Dermatol 50 33 40

24. BringhurstC

WaterstonK

SchofieldO

BenjaminK

ReesJL

2004 Measurement of itch using actigraphy in pediatric and adult populations. J Am Acad Dermatol 51 893 898

25. CharmanC

VennA

WilliamsH

2004 The Patient-Oriented Eczema Measure: Development and Initial Validation of a New Tool for Measuring Atopic Eczema Severity From the Patients' Perspective. Arch Dermatol 140 1513 1519

26. LanganSM

WilliamsHC

2006 What causes worsening of eczema? A systematic review. Br J Dermatol 155 504 514

27. LawsonV

Lewis-JonesS

FinlayA

ReidP

OwensR

1998 The family impact of childhood atopic dermatitis: the dermatitis family impact questionnaire. Br J Dermatol 138 107 113

28. HennessyS

KindP

Measuring health status in children: developing and testing a child-friendly version of EQ-5D.

KindP

MacranS

2002 York Outcomes Research Group, Centre for Health Economics, University of York 291 310

29. TakwaleA

TanE

AgarwalS

BarclayG

AhmedI

2003 Efficacy and tolerability of borage oil in adults and children with atopic eczema: randomised, double blind, placebo controlled, parallel group trial. BMJ 327 1385

30. 2007 SCST 2007 Stata Statistical Software: Release 10 College Station TX