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The latest evidence for practice

Does a clean house and dietary supplements reduce the risk of asthma in young children?

Una Adderley
Community Tissue
Viability Prescribing

Asthma rates are steadily increasing in the Western World. Both parents and healthcare professionals are keen to offer any intervention that may reduce the risk of developing asthma in young childhood.
This Australian randomised controlled trial compared two home-based asthma prevention interventions, which were designed to work within family routines. A total of 616 pregnant women, whose unborn child was at an increased risk of asthma because of a first-degree asthmatic relative, were recruited. Any babies born with congenital abnormalities, low birth weight or before 36 weeks were withdrawn from the trial.
All families received environmental control information. However, the intervention group also received allergen impermeable mattress covers and benzyl benzoate to add to the laundry every three months. The diet intervention group received capsules of omega-3/omega-6 fatty acids to add to the child's diet. The control group received capsules of polyunsaturated oils. The children were followed for five years. Neither intervention reduced asthma rates compared with the control groups.
A commentary notes that the findings of this high-quality study are consistent with other similar studies. Therefore, these interventions cannot be recommended as preventive strategies for families. The trial confirms that asthma is a multifactorial condition with multiple components including environmental, genetic and lifestyle components.

Marks GB, Mihrshahi S, Kemp AS, et al. Prevention of asthma during the first five years of life: a randomized controlled trial. J Allergy Clin Immunol 2006;118:53-61.

Horner SD. Evid Based Nurs 2007;4:44.

Are over-the-counter medications effective
for gastro-oesophageal reflux disease?

Gastro-oesophageal reflux disease (GORD) is on the increase and many patients will initially seek over-the-counter medication to manage their symptoms.

This American systematic review combined the results of 14 randomised controlled trials that had compared an antacid, alginate-antacid combination, or histamine-2 receptor antagonist (H2RA) at over-the-counter doses with placebo to treat GORD in adults.
The review found that antacids provided greater subjective improvement and less use of rescue antacids than a placebo. The alginate-antacid combination also provided greater subjective improvement than a placebo. H2RAs provided better relief of symptoms, greater subjective improvement and less use of rescue antacids than placebo. 
A commentary notes that although this review clearly showed the effectiveness of these over-the-counter medications compared to placebo, healthcare professionals should be cautious when counselling patients with regard to self-medication. Patients should be encouraged to seek clinical advice when over-the-counter remedies are not effective or stop being effective. It is possible that over-the-counter remedies may mask a more serious disease.

Tran T, Lowry AM, El-Serag HB. Meta-analysis: the efficacy of over-the-counter gastro-oesophageal reflux disease therapies. Aliment Pharmacol Ther 2007;25:143-53.

Strickland DS. Evid Based Nurs 2007;7:76.