LAUSR

BACKGROUND Associations between gluten intake and psoriasis, psoriatic arthritis and atopic dermatitis are poorly understood. OBJECTIVE To determine whether increased gluten intake is associated with incident psoriasis, psoriatic arthritis, and atopic dermatitis. METHODS Cohort studies among women in Nurses' Health Study II. Gluten content of participants' diet was calculated every four years (1991-2015 for psoriatic disease, 1995-2013 for atopic dermatitis) using food frequency questionnaires. Disease outcomes were assessed by self-report and subsequently validated. We used multivariable-adjusted Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between gluten intake (quintiles) and psoriasis, psoriatic arthritis and atopic dermatitis. RESULTS We included 85,185 participants in the psoriasis analysis, 85,324 in the psoriatic arthritis analysis and 63,443 in the atopic dermatitis analysis. Increased gluten intake was not associated with any of the outcomes (all Ptrend>0.05). Comparing highest and lowest gluten intake quintiles, the multivariable HR (95% CI) were 1.15 (0.98-1.36) for psoriasis, 1.12 (0.78-1.62) for psoriatic arthritis and 0.91 (0.66-1.25) for atopic dermatitis. LIMITATIONS No assessment of strictly gluten-free diet. CONCLUSIONS Our findings do not support the amount of dietary gluten intake as a risk factor for psoriasis, psoriatic arthritis or atopic dermatitis in adult women.