Is psoriasis associated with dementia or cognitive impairment?.Psoriasis is a multisystemic inflammatory disorder that has an unclear association with cognitive dysfunction. This Critically Appraised Topic synthesizes the results from relevant observational studies.A systematic literature search of PubMed and Embase was conducted on 12th July 2019 to identify case-control, cross-sectional, or cohort studies that investigated the association between psoriasis and cognitive impairment or dementia. Risk of bias was assessed for each study, and the results presented in a narrative synthesis.11 studies were included for critical appraisal. Ten of 11 studies compared a total of 16,574 psoriasis cases compared to over 45,078 controls for risk of dementia or cognitive impairment. One of the 11 studies evaluated 7,118 dementia patients for the odds for psoriasis compared to 21,354 controls. Six studies were assessed to have higher risk of bias. Nine out of 11 of the included studies found a significant positive association between the two diseases, one study a null association, and one study an inverse association.Most studies found a positive association between psoriasis with either mild cognitive impairment or dementia. Brief cognitive assessments has been suggested to screen older psoriasis patients who present with subjective cognitive complaints.