Prevalence of psoriasis in indigenous communities around the world: a scoping review^⋆

Psoriasis is a chronic inflammatory condition with systemic comorbidities and significant impacts on quality of life. Its prevalence in indigenous populations is poorly understood, limiting targeted health interventions. This scoping review aims to review the prevalence of psoriasis in indigenous communities globally, identify genetic, environmental, and socioeconomic influences, and explore barriers to accurate diagnosis and care. A search of PubMed, Ovid MEDLINE, Cochrane Library, and Scopus identified 30 studies, of which 15 met inclusion criteria, encompassing 13 Indigenous populations across six continents. Almost all indigenous groups exhibited markedly lower psoriasis prevalence compared to global estimates, with zero prevalence reported in the Taiwan Ami, Tanzanian Maasai, and Aboriginal groups in Brazil and Peru, and anecdotally rare in Aboriginal people of Australia, Native Alaskans, First Nation Canadians, and Native Americans. The majority of indigenous populations demonstrated a lower prevalence of psoriasis than their respective national population. Factors including protective genetic and environmental triggers, degrees of ultraviolet exposure, environmental influences, and cultural and traditional lifestyles are postulated explanations. However, limited access to specialists, diagnostic challenges in skin of colour, and cultural differences impede accurate estimation of prevalence. Standardised research methodologies and culturally sensitive healthcare strategies are crucial to address disparities and improve recognition in these communities.