What factors exacerbate eczema?

Individuals suffering from eczema have a fragile skin barrier and hydrolipidic film, and are often prone to significant dryness, known as xerosis, between eczema flare-ups. This hydrolipidic film plays a crucial role in skin protection, limiting the penetration of allergens. To combat skin dryness and strengthen this film, it is recommended for those suffering from eczema to apply a emollient balmdaily, which has moisturising and protective properties.

Sweating can be a source of skin irritation, especially in areas affected by eczema. Indeed, it can cause burning or tingling sensations. This is largely due to the natural acidity of sweat, which has a pH level between 4 and 6. Additionally, it contains sodium chloride, or salt, which has a drying effect on the skin. Dry skin, in turn, is a factor that can exacerbate eczema. Therefore, it is recommended that individuals suffering from eczema take a quick shower immediately after physical activity, followed by the application of an emollient.

Stress has a highly negative impact on most skin conditions, including eczema. Several biological mechanisms are at play, among which is the degranulation of mast cells, immune cells involved in allergic reactions. This is mediated by neuropeptides released by cutaneous nerve fibres: CRH (Corticotropin Releasing Hormone), neurotensin, substance P and other tachykinins. The release of these hormones triggers a cascade of reactions leading to the release of mediators responsible for the itchiness of eczema and the dilation of blood vessels.

It has been demonstrated that colonisation by certain parasites can exacerbate eczema. A recent study highlighted, using a murine model mimicking a case of dermatitis, that fungi of the Malassezia genus could trigger an increased release of interleukins 17 and 23 (IL-17 and IL-23). These cytokines, in turn, worsen eczema and skin inflammation more generally.

Eczema often becomes more severe in winter. Indeed, the cold air during this time of the year is conducive to dryness and skin irritations, which are exacerbating factors for eczema. It is therefore advisable to dress warmly in winter and to use gloves, as the hands are often the first victims of the winter cold. We also recommend using a nourishing hand cream in winter, and reapplying as often as you feel the need.

Several studies have demonstrated a link between pollution and the worsening of eczema. It has been specifically proven that exposure to fine diesel particles can increase itching in children suffering from eczema. Furthermore, air pollution can also trigger an increase in the production of free radicals in the body, species that cause cellular damage and exacerbate skin inflammation.

Smoking is an exacerbating factor for eczema due to the irritating and polluting substances that a cigarette contains. These compounds easily penetrate the delicate skin barrier of atopic skins and trigger immune responses that cause eczema flare-ups. Moreover, it is estimated that a single puff of cigarette smoke releases 200,000 free radicals. Thus, whether active or passive, smoking is currently considered the main aggravating factor for eczema.