Feathers vs synthetic

Feather bedding was formerly considered a potential source of allergen exposure and thus a potential risk factor for allergic diseases.¹⁸ Recommendations were made for people at risk of allergy to choose “cleaner” synthetic materials (eg polyester or dacron pillows, quilts or doonas).

Current evidence challenges this view, with growing evidence for an association between synthetic bedding materials and increased childhood wheeze.^57-61 Recent studies have the following findings.

• A cross-sectional analysis of the childhood component of a birth cohort study¹⁹ found that feather quilt use was associated with reduced HDM sensitisation and reduced frequent wheeze episodes over the past year. Children using a feather quilt were less likely to be sensitised to HDM and were less likely to have severe asthma symptoms. The reduction in symptom severity was particularly marked in children with HDM sensitisation.
• Synthetic bedding was strongly and consistently associated with frequent childhood wheeze. Substantial trends were evident for an association of increasing number of synthetic bedding items with frequent wheeze and with increasing wheeze frequency. Among children with asthma, the age of onset of asthma if synthetic bedding was used in infancy.⁶
• The Cochrane review into feather vs synthetic bedding in the management of asthma²⁰ found that recent epidemiological studies suggest that feather bedding is associated with less frequent wheeze than synthetic fillings but the evidence is insufficient to assess clinical benefits in asthma management.
• A prospective cohort study assessing the risk of bronchial obstruction during the first two years of life found that the use of a feather quilt in early life does not seem to increase the risk of asthma later in childhood.¹⁸
• A cross-sectional analysis found an adverse effect associated with synthetic quilt use on frequent wheeze and postexercise lung function among children who slept supine but not among children who did not sleep supine.²¹

Possible mechanisms for the inverse association between feather bedding and wheeze may include:¹⁹

• lower HDM allergen levels proximal to the sleeping child’s airways, as feather bedding has substantially lower HDM allergen levels than synthetic bedding^{62, 63}
• volatile organic compounds or other products in synthetic bedding may enhance sensitisation and associated symptoms (see below)^{60, 64}
• bacterial endotoxin levels may be higher in
  feather bedding, resulting in reduced allergen sensitisation.^{19, 65}

The association may also reflect selection bias associated with preferential choice of synthetic
bedding for children at risk of later allergic asthma.⁵⁹ 

Prospective studies are required to examine the link between synthetic bedding and childhood wheeze and to evaluate the role of upper bedding in asthma.^{6, 57, 58}