PASI and QoL: A New Approach to Treatment Goals

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Psoriasis is a chronic inflammatory skin disorder that significantly impacts patients' quality of life (QoL). Characterized by erythematous plaques with scaling, psoriasis not only causes physical discomfort but also has profound psychological and social consequences. The Psoriasis Area and Severity Index (PASI) is a widely utilized tool to assess the severity of psoriasis, and treatment efficacy is often measured by PASI improvement rates. Recently, the treatment goal has shifted from PASI 75, which represents a 75% improvement in symptoms, to PASI 90 and complete skin clearance (PASI 100), as these higher response rates better correlate with improvements in patient QoL.¹

PASI and Quality of Life

The Dermatology Life Quality Index (DLQI) is another crucial metric in psoriasis management. The DLQI is a 10-item questionnaire that assesses various aspects of daily life affected by psoriasis, including symptoms, emotional well-being, daily activities, leisure, work, and relationships. Studies indicate that achieving DLQI 0/1, which denotes minimal impact on QoL, should be a key treatment objective.²

Understanding the relationship between PASI and DLQI has led to a reconsideration of treatment goals. The calculation of PASI improvement rates can be complex in clinical settings, prompting a shift toward using absolute PASI values as a more practical and potentially superior indicator of treatment success. Puig et al. found that patients with an absolute PASI score of 2 or less frequently achieved PASI 90, suggesting a strong correlation between lower absolute PASI values and improved QoL.³

Study Overview

A study conducted at Nagoya City University Hospital aimed to investigate the role of absolute PASI values in achieving DLQI remission.4 The study analyzed data from 235 patients (175 men and 60 women) treated with 1 of 4 biologics— infliximab, adalimumab, ustekinumab, or secukinumab—over a period from 2012 to 2015. A total of 3,526 data points were collected at intervals ranging from 2 to 8 weeks.

Key patient characteristics included a median disease duration of 18.9 years and a baseline PASI score of 18.2. The study found a significant positive correlation between PASI and DLQI scores (r = 0.5696, P < 0.001). Receiver operating characteristic curve analysis determined that an absolute PASI score of 2.2 was the threshold for achieving DLQI remission, with an area under the curve (AUC) of 0.8140. Furthermore, 82.6% of patients who achieved PASI 100 also attained DLQI 0/1 status. However, a small percentage of patients with a PASI score of 0 still reported a DLQI score of ≥10, indicating that factors beyond visible skin symptoms, such as stigma or residual disease burden, may affect QoL.

Clinical Implications

The findings underscore the importance of targeting an absolute PASI score of <2.2 to optimize QoL outcomes in patients with psoriasis. This shift from relative PASI improvement rates to absolute PASI values could facilitate more accurate treatment assessments and better align therapeutic strategies with patient-centered outcomes. Moreover, researchers suggested clinicians should consider psychological and social factors when evaluating treatment success, as achieving skin clearance alone does not guarantee improved QoL.

Conclusion

Researchers stated psoriasis management should not solely focus on skin clearance but also on comprehensive patient well-being. The use of absolute PASI values in conjunction with DLQI assessments provides a more effective means of evaluating treatment success. They suggested future research should explore additional factors influencing QoL in patients with psoriasis to develop holistic and personalized treatment approaches.

References

1. Puig L. PASI90 response: the new standard in therapeutic efficacy for psoriasis. J EurAcad Dermatol Venereol. 2015;29(4):645-648. doi:10.1111/jdv.12817
2. Finlay AY, Khan GK. Dermatology Life Quality Index (DLQI)--a simple practical measure for routine clinical use. Clin Exp Dermatol. 1994;19(3):210-216. doi:10.1111/j.1365-2230.1994.tb01167.x
3. Puig L, Dossenbach M, Berggren L, Ljungberg A, Zachariae C. Absolute and relative Psoriasis Area and Severity Indices (PASI) for comparison of the efficacy of ixekizumab to etanercept and placebo in patients with moderate-to-severe plaque psoriasis: An integrated analysis of UNCOVER-2 and UNCOVER-3 outcomes. Acta Derm Venereol. 2019;99(11):971-977. doi:10.2340/00015555-3245
4. Nishida E, Morita A. The required absolute PASI score to achieve DLQI remission. J Dermatol. Published online March 26, 2025. doi:10.1111/1346-8138.17723