Improvement of depressive symptoms in patients with moderate-to-severe psoriasis treated with ustekinumab: an open label trial validated using beck depression inventory, Hamilton depression rating scale measures and 18 fluorodeoxyglucose (FDG) positron emission tomography (PET).

Background: Psoriasis is a chronic skin disease associated with psychiatric co-morbidities, especially depression. Early detection of psychological vulnerability in patients with psoriasis seems to be of great clinical importance and significantly impacts the quality of life of the patients.
Objectives: We sought to clarify the association between psoriasis and depressive symptoms in patients with moderate-to-severe psoriasis, and to determine the risk factors for depressive symptoms and analyze the effect of ustekinumab on the symptoms. We also aimed to evaluate the changes in glucose metabolism using ¹⁸ fluorodeoxyglucose (FDG) positron emission tomography (FDG-PET).
Methods: Fifteen patients with moderate-to-severe psoriasis scheduled to be treated with ustekinumab were enrolled. At baseline and after achieving a 75% reduction in the Psoriasis Area and Severity Index (PASI) score (PASI75), all patients underwent a psychiatric interview and FDG-PET. Fifteen healthy volunteers were enrolled for comparison.
Results: Patients with moderate-to-severe psoriasis were more depressed than those in the control group were (p < .05). The severity of psoriasis at baseline did not correlate with the depression symptoms. Treatment with ustekinumab significantly reduced the depressive symptoms, as verified using Beck Depression Inventory and Hamilton Depression Rating Scale psychiatric interviews (p < .05). However, FDG-PET of the brain showed no significant difference before and after PASI75 achievement using ustekinumab injection.
Conclusions: Patients with moderate-to-severe psoriasis are at an increased risk for depressive symptoms, and treatment with ustekinumab may be beneficial. FDG-PET does not reflect the changes in depressive symptoms in such patients.