Atopic Dermatitis, Systemic Inflammation Not Linked to Dementia Risk

This article was originally published on Dermatology Times®. It has been lightly edited.

Atopic dermatitis (AD) and systemic inflammation are not linked to a risk of dementia, according to a recent study published in the Journal of the European Academy of Dermatology and Venereology Clinical Practice.

Researchers involved in the study noted that inflammation, including inflammation caused by AD, has been previously linked to the development of other chronic diseases, and systemic inflammation may trigger nervous system inflammation—an important step in the development of dementia. However, they noted that only 3 prior studies have explored a potential link between inflammatory AD, erythrocyte sedimentation rate (ESR), and a risk of dementia.

Researchers used data from a Swedish register, which includes all individuals who had lived in Sweden between 1990 and 2018, to establish 3 exploratory cohort groups.

Cohort 1 consisted of men (n = 795,680) who were born between 1951 and 1968, all of whom had underwent a conscription examination at 18 years old, receiving diagnoses confirmed by a clinician or medical records. Due to discontinuance of the measurement of ESR during these examinations, researchers analyzed a subgroup of this population: those who were born up to the year 1966.

Cohort 2 (n = 1,757,600) consisted of all members of cohort 1—this time, including any men and women who were born during the same time period who had not undergone a conscription examination. Cohort 3 (n = 3,988,783) consisted of all members of cohorts 1 and 2, additionally including any individuals born between 1930 and 1950. Due to a lack of conscription examination participation in a portion of these patient cohorts, researchers utilized inpatient and outpatient records from the National Patient Register (NPR) to source for AD diagnoses.

Researchers also used the NPR to determine time of onset of dementia, or the Cause of Death Register (CDR) to determine whether dementia was a contributory cause of death in patients. Time of onset was established as 3 years before NPR diagnosis and 5 years prior to CDR-recorded death.

Woman scratching her atopic dermatitis | Image credit: Monstar Studio - stock.adobe.com

Among members of cohort 1, the rate of dementia for individuals without AD was 21.7 per 100,000 person-years. For those with AD, the rate of dementia was 13.1 per 100,000 person-years. This risk was nonsignificantly lower for those with AD.

Among members of cohort 2, the rate of dementia among those without AD was 23.7 per 100,000 person-years and 21.9 per 100,000 for those with AD. Researchers observed no significant difference in risk of dementia among status of AD diagnosis.

In cohort 3, individuals with an AD diagnosis had an observable significantly lower risk of dementia (77.0 per 100,000 person-years) than those without AD (181.2 per 100,000 person-years).

“The results of this study do not support the hypotheses that systemic inflammation measured by ESR in late adolescence or AD diagnosed at any point in life are associated with higher risk of dementia,” the authors wrote.

Reference

Vingeliene S, Hiyoshi A, Carlberg M, et al. Atopic dermatitis, systemic inflammation and subsequent dementia risk. JEADV Clin Pract. doi:10.1002/jvc2.249