Aims: To evaluate the prevalence of systemic diseases associated with dermatoses and conventional risk factors in patients with acute ischemic stroke (AIS). We hypothesized that conventional risk factors would not be overrepresented in AIS admissions of patients with dermatoses. Methods: Cross-sectional study. We ascertained admissions of AIS with and without the following: systemic lupus erythematosus (SLE), psoriasis (PSO), scleroderma (SSc), dermatomyositis (D-MS), bullous pemphigoid (BP), and Behcet's disease. Results: 6,454,877 admissions had a primary diagnosis of AIS of whom 34,345 had dermatoses. The prevalence of dermatoses within AIS was 0.5% (95% CI 0.32-0.55). Prevalent dermatoses at the time of AIS admission were SLE (63%), PSO (18%), SSc (12%), D-MS (4%), and BP (2%). There were no significant differences in the prevalence of traditional risk factors among dermatoses; however, these patients tended to be younger women. Hospital days of care (median 4, IQR 3-8, vs. 5, IQR 3-9, p = 0.005) and in-hospital mortality were lower (5 vs. 7%, p = 0.05) for those admissions of AIS patients with dermatoses. Conclusions: The prevalence of systemic diseases associated with dermatoses is rare in admissions of patients with AIS. Traditional risk factors were not overrepresented in AIS admissions with dermatoses. In-hospital mortality and length of stay were significantly lower in admissions of patients with AIS and dermatoses. (C) 2013 S. Karger AG, Basel