Psoriasis is associated with fissured tongue but not geographic tongue: a prospective, cross-sectional, case-control study.

BACKGROUND AND OBJECTIVES: It has been postulated that psoriasis is associated with tongue lesions and geographic tongue might be "oral psoriasis". However, reports are inconclusive, prevalence rates vary and data for Europe are sparse. In this prospective case-control study we investigated the point-prevalence of tongue conditions in an Austrian cohort. PATIENTS AND METHODS: Psoriasis patients and healthy volunteers were assessed regarding tongue and skin lesions, age, sex, smoking habits, allergies, onset of psoriasis, PASI scores and anti-psoriatic treatment. RESULTS: We included 173 psoriasis patients, 58 women, 115 men (median age: 50 [37-60] years), and 173 volunteers, 79 women, 94 men (median age: 54 [43-64] years). Overall, 95 subjects had allergies, 64 psoriasis patients and 50 volunteers were smokers. Median age at onset of psoriasis was 26 (12-40) years, the median PASI score was 2 (0-4.1), most patients received ustekinumab (n = 47). Fissured tongue was significantly associated with psoriasis (25 [14.4 %] psoriasis patients, 13 [7.5 %] volunteers; P = 0.04). Geographic tongue was present in four individuals of each group (2.3%) and associated with smoking (P = 0.01) but not with psoriasis. CONCLUSIONS: Overall, we found a low point-prevalence of tongue lesions in this Austrian cohort. Psoriasis was associated with fissured tongue but not with geographic tongue. Thus, we cannot corroborate the hypothesis that geographic tongue is an oral manifestation of psoriasis.