Alzheimer's disease and skin: a comprehensive look from neurodegeneration to skin immunity

This article addressed Alzheimer's disease (AD) as the most common cause of dementia and a global health problem, characterized by progressive cognitive decline, loss of autonomy, and a high family and social impact. Its historical evolution and current definition as a specific neuropathological entity, associated with the presence of senile plaques and neurofibrillary tangles with temporoparietal predominance, were described. The epidemiological magnitude of AD was analyzed in the context of population aging, highlighting its growing prevalence and projections of increase in middle- and low-income countries. Likewise, its clinical manifestations, both cognitive and behavioral, were reviewed, and its multifactorial etiology, involving genetic, vascular, metabolic, environmental, and infectious factors, was discussed. In particular, emerging hypotheses linking inflammatory processes, bacterial, viral, and fungal infections, oxidative stress, and alterations in the microbiota with neurodegenerative mechanisms were explored. Taking a comprehensive approach, the study expanded the analysis to include the skin as a barrier and immunoregulatory organ, describing the structural, functional, and immunological changes characteristic of skin aging. It examined how these changes, together with immunosenescence, malnutrition, comorbidities, and self-care difficulties present in patients with AD, increased susceptibility to skin infections, especially superficial mycoses. The study integrated knowledge from neurology, dermatology, and immunology, allowing us to infer that people with AD were more predisposed to skin pathologies compared to the population without dementia. Finally, the importance of an interdisciplinary approach aimed at prevention, early detection, and comprehensive management was highlighted, with the aim of improving the quality of life and overall care of these patients.