Khalaf Kridin, Dennis Linder, Guy Shalom, Stefano Piaserico, Meir Babaev, Tamar Freud, Doron Comaneshter, Arnon D. Cohen
DOI: 10.2340/00015555-3595

Data regarding the association between psoriasis and dementia are inconclusive. The aim of this study was to evaluate this association in the database of Clalit Health Services, Israel. A comparative analysis for the association between psoriasis, dementia and its risk factors was performed for the entire study population and in the subgroup of patients with moderate-to-severe psoriasis. The study included 121,801 patients with psoriasis, of whom 16,947 were diagnosed with moderate-to-severe psoriasis, and 121,802 controls. Psoriasis was associated with a lower prevalence of dementia relative to control subjects (1.6% vs 1.8%; odds ratio (OR) 0.85; 95% confidence interval (95% CI) 0.80–0.91; p < 0.001). Multivariate analysis adjusting for demographic variables, cardiovascular-related risk factors, and healthcare utilization demonstrated a significant inverse association between psoriasis and dementia in the entire study population (adjusted OR 0.86; 95% CI 0.76–0.96; p = 0.009), but not in the subgroup of patients with moderate-to-severe psoriasis (adjusted OR 0.91; 95% CI 0.81–1.02; p = 0.113). In conclusion, these data support the hypothesis that psoriasis is inversely associated with dementia.

Psoriasis, a chronic inflammatory skin disease, often presents with other diseases, such as cardiovascular disease, depression, etc. Little is known about the relationship between psoriasis and dementia, and the frequency of dementia in people with psoriasis compared with those without psoriasis. To evaluate the association between psoriasis, dementia and dementia-related risk factors, this study compared data from more than 120,000 patients with psoriasis with that from similar individuals without psoriasis. The results indicate that patients with psoriasis have a lower risk of developing dementia. The high number of patients studied implies that these results reflect the actual situation.