A review of disease burden and clinical management for generalized pustular psoriasis in China

Epidemiology and distribution of 207 rare diseases in China: A systematic literature review

Epidemiological data on rare diseases in China are currently limited. The objective of this study was to provide a comprehensive understanding of the prevalence and incidence of rare diseases by systematically analyzing the available epidemiological data. We conducted a comprehensive search of English and Chinese databases, the Incidence and Prevalence Database, the Chinese Rare Disease Guideline, and the Taiwan Health Promotion Administration from 2010 to 2023. We identified the top diseases and regions based on epidemiological data and present the maximum, minimum, and median prevalence and incidence values in tables and forest plots. 1,264 prevalence and incidence data were retrieved from 277 studies, guidelines and official websites, covering 110 rare diseases (53.1%) and 32 regions (94.1%). In terms of geographical regions, incidence or prevalence data were available for 32 regions (94.1%), excluding Tibet Hui Autonomous Region and Macao Special Administrative Region. In terms of rate, 60 and 77 out of 207 diseases (29.0% and 37.2%) had available incidence and prevalence data, respectively. Eight diseases had an incidence rate equal to or greater than that of 1,000 patients per million. The present study provides a comprehensive epidemiological analysis and valuable insights into the prevalence and incidence of rare diseases in China. Our findings underscore the pressing need for sustained drug research and medical support for individuals and families impacted by rare diseases.

Tobacco smoking negatively influences the achievement of greater than three-quarters reduction in psoriasis area and severity index after eight weeks of treatment among patients with psoriasis: Findings from a prospective study

INTRODUCTION

Smoking is an independent and modifiable risk factor for the onset and development of psoriasis; however, evidence on the association between tobacco smoking and psoriasis treatment efficacy is limited. This study aimed to explore the influence of smoking on treatment efficacy in a cohort of patients with psoriasis in Shanghai, China.

METHODS

Patients with psoriasis were recruited from the Shanghai Skin Disease Hospital between 2021 and 2022. The treatment for patients with psoriasis includes acitretin, methotrexate, narrow-band ultraviolet/benvitimod, and biologics. Data were collected using a structured questionnaire, physical examination, and disease severity estimation at baseline, week four, and week eight. The achievement of a ≥75% reduction in psoriasis area and severity index (PASI75) score from baseline to week 8 was set as the primary outcome for treatment efficacy estimation. Data were analyzed using SAS 9.4.

RESULTS

A total of 560 patients with psoriasis were enrolled in this study, who were predominantly males (72.9%). The average age of patients was 48.4 years, and 38.8% of them were current smokers, 5.0% of them were former smokers. The median score of PASI among patients changed from 11.1 (interquartile range, IQR: 7.9-16.6) at baseline to 6.2 at week 4 and 3.1 at week 8, and 13.8% and 47.3% of patients with psoriasis achieved PASI75 at weeks 4 and 8, respectively. Logistic regression indicated that patients without tobacco smoking had a higher proportion of PASI75 achievement at week 8. The adjusted odds ratio (AOR) was 11.43 (95% CI: 6.91-18.89), 14.14 (95% CI: 8.27-24.20), and 3.05 (95% CI: 1.20-7.76) for non-smokers compared with smokers, current smokers, and former smokers, respectively. Moreover, former smokers had higher PASI75 achievement than current smokers (AOR=3.37), and patients with younger smoking initiation age, longer smoking duration, and higher smoking intensity had lower PASI75 achievement.

CONCLUSIONS

Tobacco smoking was negatively associated with PASI75 achievement both in current and former smokers, and former smokers had higher PASI75 achievement than current smokers. The implementation of tobacco control measures is beneficial for improving treatment responses.

Acquired diffuse palmoplantar erythema with keratoderma in Chinese patients with pustular psoriasis: A predictor for IL36 receptor antagonist c.115+6T>C mutation?

Several studies have suggested that mutation of the interleukin 36 receptor antagonist gene (IL36RN) is related to generalized pustular psoriasis (GPP), and the presence of IL36RN mutation may affect the clinical manifestations and treatment responses. However, genetic testing is not routinely available in clinical practice for the diagnosis of GPP. Previously, GPP patients with acrodermatitis continua of Hallopeau (ACH) were found to have a high percentage of carrying IL36RN mutation. In this study, we reported six patients with pustular psoriasis presenting as diffuse palmoplantar erythema with keratoderma among 60 patients who carried IL36RN mutation. ACH was present in five patients and five patients had acute flare of GPP. This unique presentation may serve as a predictor for IL36RN mutation in patients with pustular psoriasis, similar to ACH.

Better efficacy, lower recurrence rate and decreased CD8+TRM with guselkumab treatment for generalized pustular psoriasis: A prospective cohort study from China

Generalized pustular psoriasis (GPP) is a severe and uncommon form of psoriasis, for which treatment options are limited. There is an urgent need to expand the treatment options for GPP. Currently, adalimumab, secukinumab, and guselkumab are considered effective for GPP, but there is a lack of prospective direct comparative studies on their efficacy for GPP. We conducted a prospective, single-center, observational study on 50 GPP patients to compare the efficacy, safety, and recurrence rates of these three biologics. Adalimumab, secukinumab, and guselkumab resulted in varying degrees of improvement in patients with GPP, but guselkumab exhibited superior efficacy and a lower recurrence rate than the other two drugs. This enhanced response may be attributed to the significant reduction in CD8+ tissue-resident memory T cells within GPP lesions caused by guselkumab.

Clinical and Disease Burden of Patients with Generalized Pustular Psoriasis: A Review of Real-World Evidence

Generalized pustular psoriasis (GPP) is a chronic, rare, and potentially life-threatening disease. There is limited understanding of patient characteristics in GPP and their correlation with disease progression or healthcare resource utilization. Our review aims to examine real-world evidence on these characteristics and the associated disease burden as related to economic and quality of life factors. Results showed that most patients with GPP experienced flares once a year, lasting from 2 weeks to 3 months, with > 80% of patients having residual disease post-flare, with/without treatment, indicating the long-term nature of GPP. The impact of GPP on patients' daily activities was significant, even in the absence of a flare. GPP adversely affected mental health, and anxiety and depression were reported regularly. Patients with GPP had more comorbidities, were prescribed more medication, and had more inpatient and outpatient visits than in matched plaque psoriasis or general population cohorts. Improving the education of healthcare providers in diagnosing GPP, defining disease flares, and managing the disease, as well as making globally accepted clinical guidelines for GPP treatment available, could help to reduce the burden on patients with GPP. Effective therapies that control and prevent GPP flares and manage chronic disease are needed.

Characteristics and Burdens of Disease in Patients from Beijing with Generalized Pustular Psoriasis and Palmoplantar Pustulosis: Multicenter Retrospective Cohort Study Using a Regional Database

BACKGROUND AND OBJECTIVE

Pustular psoriasis is a chronic and recurrent autoimmune disease, although little is known about the disease burden of pustular psoriasis in China. We analyzed the characteristics and disease burdens of patients from Beijing who had generalized pustular psoriasis (GPP) or palmoplantar pustulosis (PPP).

METHODS

This multicenter retrospective cohort study used a regional electronic health database that covered 30 public hospitals in Beijing. From June 2016 to June 2021, all patients with a diagnosis of GPP, PPP, or psoriasis vulgaris (PV) were identified by International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes. The GPP and PPP cohorts were separately matched with patients with PV in a 3:1 ratio for comparisons. Demographic data, clinical characteristics, healthcare resource utilization, and costs were collected. Descriptive and comparative analyses were used to compare the cohorts.

RESULTS

There were 744 patients with GPP (46.8% men; age 42.14 ± 21.47 years) and 4808 patients with PPP (35.5% men; age 51.65 ± 16.12 years); 14.5% of patients with GPP had concomitant PV and 7.5% of patients with PPP had concomitant PV. Relative to matched patients with PV, patients with GPP had a higher prevalence of erythrodermic psoriasis (5.9% vs 0.4%, p < 0.0001), psoriatic arthritis (3.1% vs 1.5%, p = 0.007), and organ failure (1.1% vs 0.2%, p = 0.002). Relative to matched patients with PV, patients with PPP had a higher prevalence of cerebrovascular disease (4.7% vs 1.2%, p < 0.0001), thyroid dysfunction (3.9% vs 3.3%, p = 0.035), and type 2 diabetes mellitus (6.8% vs 5.9%, p = 0.030). More patients with GPP than patients with PV received systemic non-biological agents (27.9% vs 3.3%, p < 0.0001) and biologic agents (4.8% vs 2.0%, p = 0.010). More patients with PPP than patients with PV received topical agents (50.9% vs 34.7%, p < 0.0001) and systemic non-biological agents (17.8% vs 2.7%, p < 0.0001). More patients with GPP than patients with PV required inpatient hospitalization (22.0% vs 7.8%, p < 0.0001). Hospitalization stay was longer in patients with GPP than patients with PV (11.72 ± 0.45 vs 10.38 ± 0.45 days, p = 0.022). More patients with PPP than patients with PV had emergency visits (16.3% vs 12.8%, p < 0.0001). The GPP and PPP cohorts and their matched PV cohorts had no significant differences in costs. However, patients with PPP had lower outpatient costs than patients with PV (368.20 ± 8.19 vs 445.38 ± 5.90 Chinese Yuan per patient per month, p < 0.0001).

CONCLUSIONS

Patients from Beijing with GPP and PPP had higher disease burdens than matched PV cohorts, including the prevalence of comorbidities, healthcare resource utilization, and medication burden. However, the economic burden of pustular psoriasis was similar to that of PV. Practical and specific therapies are needed to reduce the burdens of pustular psoriasis.

Current management of generalized pustular psoriasis

Generalized pustular psoriasis (GPP) is a rare subset of psoriasis involving episodes of sterile pustules accompanied by inflammation and, often, systemic involvement. The inflammatory nature of GPP has potential for severe multisystem complications including high-output cardiac failure, infections, digestive system issues, and disfiguring or lethal acute flare episodes. The disease tends to have higher prevalence in females and Asians. The IL-1/IL-36 inflammatory pathway is a critical facet of GPP's pathology. Genetic mutations that are associated with GPP include modifications of Interleukin 36 Receptor Antagonist (IL36RN), Caspase Recruitment Domain Family Member 14 (CARD14), Adaptor Related Protein Complex 1 Subunit Sigma 3 (AP1S3), Myeloperoxidase (MPO) and Serpin Peptidase Inhibitor Clade A Member 3 (SERPINA3) genes. Treatment guidelines for GPP are not well-entrenched. Currently, only one GPP-specific treatment, the interleukin-36 receptor antagonist (IL-36Ra) spesolimab, has been approved for use in the United States. Additional anti-IL-36 pathway therapies are currently being developed. Other treatment options include other biologic therapies such as IL-17 inhibitors, IL-23 inhibitors and TNFα inhibitors. Non-biologic therapeutic options include retinoids, cyclosporine and methotrexate. Treatment options differ throughout the world; most countries utilize retinoids, cyclosporine and methotrexate as first-line non-biologic options. China and United Kingdom have no GPP-specific biologic therapies approved for use, while several biologic therapies are approved for use in Japan. This review aims to serve as an update on the current global management of GPP while also including relevant aspects of disease pathogenesis, diagnosis, clinical presentation, histopathology, aetiology and epidemiology.