The required absolute PASI score to achieve DLQI remission

Psoriasis is a chronic inflammatory skin disease that significantly impacts patients' quality of life (QoL). While the Psoriasis Area and Severity Index (PASI) has traditionally been used to assess disease severity and treatment response, achieving substantial improvement in QoL has become an increasingly important therapeutic goal. Recent advances in biologic therapies have enabled higher rates of PASI 90 and PASI 100 responses; however, PASI 75 is no longer considered sufficient for optimal patient outcomes. Calculating PASI improvement rates in daily practice remains challenging, shifting focus toward absolute PASI values as a practical indicator of disease control. In this study, we analyzed 235 psoriasis patients treated with biologics at Nagoya City University Hospital, evaluating 3526 data points collected over a maximum of 288 weeks. We found that PASI positively correlated with DLQI (r = 0.5696, p < 0.001), and that an absolute PASI score of ≤2.2 was associated with DLQI remission (AUC = 0.8140). Notably, 82.6% of patients achieving PASI 100 also achieved DLQI 0/1 status. However, 1.0% of patients with a PASI score of 0 still reported a DLQI ≥10, suggesting that factors beyond skin lesions, such as stigma or residual damage, may contribute to impaired QoL. These findings underscore the importance of evaluating absolute PASI values to guide treatment decisions and achieve DLQI remission. Additionally, the psychosocial burden of psoriasis must be addressed to ensure comprehensive care and sustained improvements in QoL.