Obesity is associated with lower PASI90, PASI75, and PASI100 responses in patients with psoriasisObesity May Impact How Well Certain Psoriasis Drugs Work

The Journal of dermatological treatment Published July 22, 2026 Study authors: Zhou Wenjing, Xu Zhentao, Yu Haibo, Wang Xiwen, Li Lixia, Pan Xinyu PubMed ↗ DOI ↗ Editorial oversight: Dr. Amelia Tan, PhD · Internal Medicine & Chronic Disease

AI-generated summary of the cited source, checked by automated accuracy review. How we work

Key Takeaway

Note that obesity is associated with lower PASI responses, but weight should not be the sole factor for selecting biologics.

This meta-analysis evaluated the impact of obesity on treatment responses among 4200 patients with psoriasis receiving IL-17, IL-12/23, TNF-alpha, or IL-23 inhibitors. The study specifically analyzed outcomes including PASI90, PASI75, and PASI100 to determine if weight status influenced efficacy.

Key findings indicate that obese patients had lower response rates for PASI90 (RR = 0.64), PASI75 (RR = 0.52), and PASI100 (RR = 0.42). Specifically, IL-17 inhibitors showed a significant negative effect in the obese subgroup (RR = 0.57), while IL-12/23 inhibitors also showed a significant negative effect (RR = 0.43). However, after trim-and-fill correction for publication bias, the PASI90 result was no longer statistically significant (RR = 0.79; 95% CI: 0.58-1.08).

The authors note that the small number of studies available for certain drug classes limits the robustness of these estimates. While an association between obesity and reduced response is noted, clinicians should not base treatment selection solely on weight status, as current evidence does not support such a definitive clinical rule.

How this fits prior evidence

This meta-analysis addresses a gap in understanding how patient characteristics like weight influence biologic efficacy. It complements existing evidence that weight-loss interventions improve psoriasis severity and quality of life in adults. While this study identifies an association between obesity and lower PASI scores, it notes that the significance of PASI90 results was affected by publication bias.

A large review of 4,200 patients looked at how weight affects the effectiveness of different biologic medications for psoriasis. The study specifically looked at IL-17, IL-12/23, and TNF-alpha inhibitors. These are common types of treatments used to manage skin symptoms.

The findings showed that obese patients had lower response rates for several measures of success, including PASI90, PASI75, and PASI100. Specifically, the data suggested a notable drop in effectiveness for IL-17 and IL-12/23 inhibitors among those with higher body weights. However, some results were less clear after adjusting for potential publication bias.

Because many of these findings come from a small number of studies, more research is needed to confirm the exact impact on specific drug classes. Doctors should consider weight as one factor when choosing a treatment, but they should not base their entire decision solely on a patient's weight. Patients should talk to their doctors about how these factors might influence their specific treatment plan.

What this means for you:

Obesity may link to lower response rates for some psoriasis biologics, but more research is needed.

Common questions

Does weight affect how well my psoriasis medication works?

The study of 4,200 patients found that obese patients showed lower response rates for several measures of success, including PASI90, PASI75, and PASI100. Specifically, the data suggested a significant negative effect on the effectiveness of IL-17 and IL-12/23 inhibitors in those with higher body weights.

Which specific drugs were affected by weight?

The research looked at several types of biologics. It found that both IL-17 inhibitors and IL-12/23 inhibitors showed lower response rates in obese patients. However, because the number of studies for these specific classes was small, more research is needed to confirm these results.

Should I change my treatment if I am overweight?

While the data shows a link between obesity and lower response rates, doctors say weight should only be one of many factors when choosing a biologic. Current evidence does not support picking a medication based solely on a patient's weight.

Study Details

Study typeMeta analysis

Sample sizen = 4,200

EvidenceLevel 1

PublishedDec 2026

PMID42480000

View Original Abstract ↓

OBJECTIVE: To evaluate the effect of obesity on biologic efficacy in psoriasis across different drug classes. METHODS: PubMed, Embase, Web of Science, and Cochrane Library were searched from inception to March 2026. Studies reporting obesity‑stratified outcomes of biologics for psoriasis were included. Primary outcome was PASI90 (Psoriasis Area and Severity Index); secondary outcomes were PASI75 and PASI100. Random‑effects model was used to calculate pooled relative risks (RRs). Subgroup analyses and meta‑regression explored heterogeneity. RESULTS: Twelve studies (4200 patients) were included. Obese patients had lower PASI90 response (RR = 0.64; 95% confidence interval (CI): 0.55-0.76; = 72%), but publication bias was present (Egger < 0.001); after trim‑and‑fill correction, RR = 0.79 (95% CI: 0.58-1.08). This finding should therefore be interpreted with caution. Significant negative effects were seen for interleukin (IL)‑17 inhibitors (RR = 0.57) and IL‑12/23 inhibitors (RR = 0.43) in subgroup analyses, but not for tumor necrosis factor‑alpha (TNF‑α) or IL‑23 inhibitors, although the small number of studies for some classes limits the robustness of these estimates. PASI75 (RR = 0.52) and PASI100 (RR = 0.42) were also lower in obese patients. Biologic class, study design, region, mean body mass index (BMI), and obesity proportion were major sources of heterogeneity. CONCLUSIONS: Obesity may be associated with reduced response to biologics in psoriasis, although the PASI90 result was affected by publication bias and became non‑significant after correction. The impact appeared to differ by class, with significant effects for IL‑17 and IL‑12/23 inhibitors in subgroup analyses, but these findings require confirmation in larger studies. Weight status should be considered as one of multiple factors when selecting biologics, but current evidence does not support treatment selection based solely on obesity.

Obesity is associated with lower PASI90, PASI75, and PASI100 responses in patients with psoriasisObesity May Impact How Well Certain Psoriasis Drugs Work

How this fits prior evidence

Common questions

Study Details

AI-OCT reports reduced false-positive DME referral rates from 69.1% to 24.1%

AI technology reduces unnecessary referrals for diabetic macular edema

Clinical research that matters. Delivered to your inbox.

Obesity is associated with lower PASI90, PASI75, and PASI100 responses in patients with psoriasisObesity May Impact How Well Certain Psoriasis Drugs Work

How this fits prior evidence

Common questions

More on Psoriasis

Study Details

AI-OCT reports reduced false-positive DME referral rates from 69.1% to 24.1%

AI technology reduces unnecessary referrals for diabetic macular edema

Clinical research that matters. Delivered to your inbox.

Related in Diabetes & Endocrinology

From Other Specialties