NEW YORK (Reuters Health) - Older patients with the inflammatory skin disorder rosacea appear significantly more likely to be diagnosed with dementia, according to Danish researchers.
As Dr. Alexander Egeberg told Reuters Health by email, "We found an increased risk of dementia, in particular Alzheimer's disease (AD), in patients with rosacea. The risk was only increased in patients older than 60 years, however."
"Emerging data," he added, "suggest a link between rosacea and neurological disorders. Yet, it is important for patients to remember that the absolute risk is still low."
In an April 28 online paper in Annals of Neurology, Dr. Egeberg, of the University of Copenhagen, and colleagues note that in rosacea there's upregulation of various inflammatory mediators, for example, cytokines, antimicrobial peptides (AMPs), chemokines, and matrix metalloproteinases (MMPs). Similar processes appear to be at work in certain neurodegenerative disorders.
To examine the possible relationship, the team studied data from 1997 to 2012 on almost 5.6 million Danes. Of these, 82,439 had rosacea at baseline. Over a maximum follow-up of 16 years, 99,040 developed dementia, of whom 29,193 were diagnosed with AD.
After adjustment, patients with rosacea were at significantly increased risk of dementia (hazard ratio 1.07) and of AD (HR 1.25). Women were at greater risk of AD (HR 1.28) than men (HR 1.16).
However, stratification by age at study entry showed that the risk of AD was significantly increased only in those enrolled at the age of 60 or more (HR 1.20). When analyses were limited to patients with a hospital dermatologist diagnosis of rosacea, the HR for dementia was 1.42 and for AD it was 1.92.
The current sum of evidence, conclude the investigators,"suggests that certain forms of dementia, in particular AD, have prominent inflammatory components, and MMPs and AMPs may provide mechanistic links for the observed association between rosacea and dementia."
"Increased focus on symptoms of cognitive dysfunction in patients with rosacea may be warranted," they say.
The authors reported no funding or disclosures.