Relationship between sensitive skin and sleep disorders, fatigue, dust, sweating, food, tobacco consumption or female hormonal changes: Results from a worldwide survey of 10 743 individuals.

BACKGROUND: Sensitive skin is related to environmental factors. OBJECTIVES: We aimed to investigate the roles of poorly known associated and triggering factors on sensitive skin in a large global population. METHODS: A survey was administrated to a representative sample of the adult population aged 18-75 years in five different countries (Brazil, China, France Russia, and the United States). All participants answered a web-based questionnaire on sociodemographic characteristics, sensitive skin and environmental factors. RESULTS: Among the 10 743 included individuals (5285 men and 5458 women), 48.2% declared that they had sensitive skin. The group with sensitive skin reported significant increases in fatigue, dust or sweating and to a lesser extent food or tobacco consumption. The members of this group also declared that they experienced more sleep disorders than individuals without sensitive skin. Sensitive skin was very frequent in pregnant women, women with painful menstruations or women using contraceptive pills. CONCLUSIONS: This large cohort study identified new factors, including female hormonal status, fatigue, sleep disorders and food, associated with sensitive skin. These associations suggest that sensitive skin is not restricted to an epidermal disorder but may be included in a larger context. The identified factors are potential upstream drivers of neurogenic inflammation in sensitive skin.

Geoepidemiologic considerations of auto-immune pemphigus.

Sporadic and endemic forms of pemphigus foliaceus exist. Incidences of the various forms of pemphigus vary from country to country: pemphigus vulgaris is most common in Europe and the USA, whereas pemphigus foliaceus is more prevalent in Northern Africa, Turkey and Southern America. Endemic pemphigus foliaceus (also known as fogo selvagem and Brazilian pemphigus foliaceus) is a variant of the disease that is frequently diagnosed in some areas of Brazil and other underdeveloped areas of the world, including Tunisia and Colombia. Both genetic and environmental factors have been associated with the occurrence of auto-immune pemphigus and endemic pemphigus is very interesting from this point of view. Most of the patients with auto-immune pemphigus are aged 40-60 years at the onset of the disease. The incidence and prevalence of pemphigus are low. The demonstration of association of pemphigus vulgaris with HLA class II alleles is supported by various studies.