Eating Increases and Exercise Decreases Disease Activity in Patients With Symptomatic Dermographism.

Background: Eating can increase disease activity in patients with symptomatic dermographism , the most common subtype of chronic inducible urticaria, but it is unclear how common this is. The effects of exercising on symptomatic dermographism disease activity have also not yet been determined.

Objective: To assess the impact of exercise and nonspecific carbohydrate-rich food intake on the severity and intensity of symptomatic dermographism after exercise and nonspecific carbohydrate-rich food intake.

Methods: We assessed disease activity by FricTest provocation testing in 75 symptomatic dermographism patients before and after eating, exercising, or both. We determined the rates of food-dependent (FD) symptomatic dermographism and food-exacerbated (FE) symptomatic dermographism. By comparing post- and pre-exercise FricTest scores, we identified complete responders: that is, patients with a negative FricTest response after exercising and partial responders. Finally, we evaluated whether exercise protects patients with FD-symptomatic dermographism or FE-symptomatic dermographism from eating-induced worsening of symptomatic dermographism.

Results: Of 64 symptomatic dermographism patients, eight had FD-symptomatic dermographism (13%), 42 had FE-symptomatic dermographism (66%), and 14 patients showed no negative impact of eating on disease activity (21%). Physical exercise reduced FricTest skin provocation test responses in 83% of 58 patients. Exercising protected patients with FD/FE-symptomatic dermographism from worsening of symptomatic dermographism owing to eating in half of cases, with higher rates for exercise after eating (67%) compared with exercise before eating (35%).

Conclusions: Our study shows that eating often worsen symptomatic dermographism symptoms, and exercise often improves it. Our findings might aid patients in controlling symptoms better.