Study IDs Rosacea-Alzheimers Link

Rosacea may be linked to an increased risk of dementia—in particular Alzheimer’s disease, new research suggests.

This risk was highest in older patients and in patients where rosacea was diagnosed by a hospital dermatologist. The new findings are published in the Annals of Neurology.

Exactly how the conditions are linked is unknown, but rosacea is characterized by elevated expression of certain proteins—including matrix metalloproteinases and antimicrobial peptides—that are also involved in various neurodegenerative disorders such as Alzheimer’s disease and other forms of dementia.

Researchers led by Alexander Egeberg, MD, PhD, a dermatologust at the University of Copenhagen in Denmark investigated the association between rosacea and dementia in Danish registers. There were 5,591,718 Danish citizens aged ≥18 between 1997 to 2012, including 82,439 patients with rosacea. Individuals were followed until December 31, 2012, migration, a diagnosis of dementia, or death from any cause, whichever came first. A total of 99,040 individuals developed dementia, of which 29,193 were diagnosed with Alzheimer’s disease.

After adjustments for potential confounding factors, patients with rosacea had a 7 percent increased risk of dementia and a 25 percent increased risk of Alzheimer’s disease compared with individuals without rosacea. Women had a 28 percent increased risk of Alzheimer’s disease and men had a 16 percent increased risk if they had rosacea. When results were stratified by age at study entry, the risk of Alzheimer’s disease was only significantly increased in individuals ≥60 years (who had a 20 percent increased risk). When analyses were limited to patients with a hospital dermatologist diagnosis of rosacea only, the increased risks of dementia and Alzheimer’s disease were 42 percent and 92 percent, respectively, the study showed.

“A subtype of patients have prominent neurological symptoms such as burning and stinging pain in the skin, migraines, and neuropsychiatric symptoms, suggesting a link between rosacea and neurological diseases,” explains Dr. Egeberg in a news release. “Indeed, emerging evidence suggests that rosacea may be linked with neurological disorders including Parkinson’s disease and now also Alzheimer’s disease.”

Further research is warranted to examine whether treating rosacea may also modify patients’ risk of developing dementia.