Automated mass screening and association rules analysis for comorbidities of psoriasis: A population-based case-control study

Patients with psoriasis frequently have comorbidities, which are linked to higher mortality rates. An in-depth investigation of comorbidities and their effects on health can help improve the management of patients with psoriasis. We conducted a comprehensive and unbiased investigation of comorbidities in patients with psoriasis and explored the pattern of association between comorbidities. A nationwide population-based study included 384 914 patients with psoriasis and 384 914 matched controls between 2011 and 2021. We used automated mass screening of all diagnostic codes to identify psoriasis-associated comorbidities and applied association rule analysis to explore the patterns of comorbidity associations in patients with psoriasis. Patients with psoriasis had an increased risk of autoimmunity-related diseases such as inflammatory arthritis, Crohn's disease, type 1 diabetes, and acute myocardial infarction. The comorbidities of patients with psoriasis with a history of cardiovascular events demonstrated strong interrelationships with other cardiovascular risk factors including type 2 diabetes mellitus, essential hypertension, and dyslipidemia. We also found comorbidities, such as malignant skin tumors and kidney and liver diseases, which could have adverse effects of anti-psoriasis therapy. In contrast, patients with psoriasis showed a decreased association with upper respiratory tract infection. Our results imply that comorbidities in patients with psoriasis are associated with the systemic inflammation of psoriasis and the detrimental effects of its treatment. Furthermore, we found patterns of associations between the cardiovascular risk factors and psoriasis. Mass screening and association analyses using large-scale databases can be used to investigate impartially the comorbidities of psoriasis and other diseases.

Genome-wide Association Study of Susceptibility Loci for Self-Reported Atopic Dermatitis and Allergic Rhinitis in the Korean Population

BACKGROUND

Allergic diseases include atopic dermatitis (AD) and allergic rhinitis (AR), which are chronic, relapsing inflammatory disorders of the skin or mucosa that usually accompany immunoglobulin E-mediated immune responses. They are complex, multifactorial diseases with an etiology involving interactions between genetic and environmental factors.

OBJECTIVE

We performed a genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with allergic diseases in the Korean population.

METHODS

A total of 8,840 samples were obtained from the Korean Association Resource Consortium dataset of the Korean Genome and Epidemiology Study Ansan-Anseong cohort. The allergic disease phenotype was determined based on self-reported physician diagnoses. After quality control, 8,823 subjects with 877,242 variants remained for the final analysis. The GWAS was performed using logistic regression analysis in an additive model adjusted for age and sex.

RESULTS

A total of 636 patients with allergic disease and 8,176 controls were analyzed. Three SNPs were associated with allergic disease at a level of genome-wide suggestive significance (p<1.0×10-5) in the Korean population: rs7275360, located in neural cell adhesion molecule 2; rs698195; and rs3750552, located in family with sequence similarity 189, member A2. These polymorphisms were on chromosomes 21q21.1, 7q31.1, and 9q21.12, respectively.

CONCLUSION

We identified 3 novel SNPs significantly associated with allergic diseases in the Korean population. Further research is required to confirm the association between these novel SNPs and allergic disease in the Korean population and in other ethnicities.

Association between cardio-cerebrovascular disease and systemic antipsoriatic therapy in psoriasis patients using population-based data: A nested case-control study

The effect of antipsoriatic therapy on cardio-cerebrovascular disease (CCVD) is not well described. Thus, we performed a population-based nested case-control study to investigate the effect of systemic antipsoriatic therapy on CCVD in psoriasis patients. Using nationwide cohort data from the Korean National Health Insurance Claims database, newly diagnosed psoriasis patients were identified. Among the enrolled participants, postenrollment development of CCVD events (ischemic heart disease, myocardial infarction, cerebral infarction, and cerebral hemorrhage) was investigated. To evaluate the effect of systemic antipsoriatic therapy on CCVD risk, we calculated the proportion of the treatment period with systemic antipsoriatic therapy during the study period (PTP [%]: the sum of all systemic antipsoriatic therapy durations divided by total observation period). Among 251 813 participants, 6262 experienced CCVD events during the study period (CCVD group). Controls included 245 551 patients without CCVD history during the study period (non-CCVD group). The non-CCVD group had greater PTP than the CCVD group (CCVD 2.12 ± 7.92, non-CCVD 2.64 ± 9.64; P < 0.001). In multiple logistic regression analysis, PTP was inversely associated with the CCVD risk after adjusting for age, sex, diabetes, hypertension, and dyslipidemia. A 10% increase in PTP reduced CCVD risk by 0.96 (95% confidence interval 0.93 to 0.99). Reduced CCVD risk was robust for both conventional antipsoriatic therapy and biologics. Our study found that systemic antipsoriatic therapy use was inversely associated with CCVD risk in psoriasis patients. These findings suggested that systemic antipsoriatic therapy could reduce CCVD development in patients with psoriasis.

Automated Mass Screening for Comorbidities of Vitiligo Using the National Health Insurance Database

Although the study design for identifying specific disease associations using a health insurance database has been well-established, few studies explore unknown comorbidities. We conducted a series of automated case-control studies for all International Classification of Disease, Tenth Revision, Clinical Modification diagnostic codes (A01-Z99) using the Korean National Health Insurance database from 2007 to 2017 to reveal undiscovered disease associations of vitiligo. A total of 90,297 patients with vitiligo and 90,297 age- and sex-matched controls without vitiligo were included, and disease associations for 1,265 relevant diagnostic codes were screened. A meta-analysis of the individual ORs for each International Classification of Disease, Tenth Revision code was performed to identify the possibility of selection bias. Finally, the association with vitiligo was significantly increased in 45 diseases and decreased in 6 diseases. We not only reaffirmed the positive correlation between vitiligo and other autoimmune diseases but also observed associations with obsessive-compulsive disorder and melanoma. In contrast, femur fracture showed a negative correlation. In this study, we attempted an automated mass screening and suggested a possible selection bias. In the era of large-scale databases, a systematic and comprehensive approach might be needed.

Risk of uveitis in patients with psoriasis in Korea: A nationwide population-based cohort study

BACKGROUND

Evidence for the association between psoriasis and uveitis according to the severity of psoriasis including psoriatic arthritis (PsA) and type of uveitis is lacking, and there are no data on the frequency or timing of recurrence of uveitis in patients with psoriasis.

OBJECTIVES

We aimed to evaluate the risk of first-occurrence and recurrence of uveitis in patients with psoriasis in the Korean population. We further evaluated the risk of uveitis according to the severity of psoriasis, comorbidity of PsA, and location of uveitis.

METHODS

In a nationwide retrospective cohort study, we compared 317,940 adult patients who had psoriasis with 635,880 matched controls. Incidence rates (IRs) and estimated IR ratios of the first occurrence and recurrence of uveitis were calculated using survival analysis and Poisson regression, respectively.

RESULTS

The rate of uveitis incidence and uveitis recurrence in patients with psoriasis were 1.18 and 2.31 per 1,000 person-years, respectively. Compared with the controls, the IR ratios of development and recurrence of uveitis in patients with psoriasis were 1.14 (95% CI 1.08, 1.2) and 1.16 (95% CI 1.12, 1.21), respectively. The recurrence rate of uveitis was highest within 3 years after the onset of psoriasis. The corresponding IR ratios for uveitis recurrence in patients with mild psoriasis, severe psoriasis, and PsA were 1.11 (1.06, 1.16), 1.24 (1.16, 1.33), and 1.49 (1.31, 1.7), respectively. Patients with psoriasis had an increased risk of recurrence of anterior uveitis, and patients with both psoriasis and PsA had an increased risk of recurrence of both anterior and pan-uveitis.

CONCLUSIONS

Patients with psoriasis had a higher risk of both development and recurrence of uveitis, especially with severe psoriasis and PsA. The timing of uveitis recurrence was related to the onset of psoriasis, and patients who had psoriasis with PsA had an increased risk of vision-threatening pan-uveitis.

Association between the cumulative dose of cyclosporine and liver enzyme abnormalities in dermatology patients managed with a low-dose regimen

Cyclosporine (CsA) is an immunosuppressive agent that specifically inhibits T cell-related immune responses. There is little evidence regarding the association between low-dose CsA administration and abnormal hepatic function in dermatology patients. This study aimed to examine the association between the cumulative dose of CsA and liver enzyme abnormalities obtained from peripheral blood tests in patients with skin diseases. A retrospective single-center study of 697 patients who were prescribed CsA for skin disease in the outpatient dermatology clinic between 2015 and 2019 were performed. Multiple logistic regression with confounder adjustment was performed to assess the association between the cumulative dose of CsA and liver enzyme abnormalities. Compared to patients with the lowest cumulative dose of CsA (˂7.0 g), patients with the highest cumulative dose of CsA (≥30.6 g) were significantly associated with an increased likelihood of developing liver enzyme abnormalities (odds ratio [OR] = 1.96; 95% confidence interval [CI] = 1.02-3.79). In the stratified analysis, patients with the highest cumulative dose of CsA (≥30.6 g) were significantly associated with a 1.5-or higher alanine aminotransferase elevation from baseline (OR = 2.26, CI = 1.08-4.73). Patients prescribed long-term, low-dose CsA up to a high cumulative dose (≥30.6 g) may be associated with an increased risk of developing liver enzyme abnormalities. However, these liver enzyme elevations were not severe in magnitude and were reversible. This article is protected by copyright. All rights reserved.

1039 RECEIVING ASSISTANCE FROM DOMESTIC ROBOTS: WHAT ARE ELDERS’ PREFERENCES?

Introduction

Aging leads to decline in physical and functional ability. Strengthening the domestic support enables elders to manage their health and living at home and reduce their need for residential service. Domestic robots can potentially provide a broad range of support to the elders. However, relatively little research attention has investigated elders’ preferences on it. This study aims to investigate elders’ preferences on receiving assistance from domestic robots.

Methods

This cross-sectional descriptive study recruited a convenient sample of 365 robotic inexperienced elders (65-99 years old). It used the Assistance Preference Checklist to assess participants’ preferences on receiving assistance from domestic robots in 48 home-based tasks under six aspects including personal care, leisure activities, health assistance, chores, information management, and manipulating objects. It used t-test and one-way analysis of variance to compare the difference in preferences between participants with different demographic and health characteristics.

Results

Overall, participants preferred domestic robots to assist in tasks under the aspect on chores, information management, and manipulating objects. Specifically, males indicated a higher preference for domestic robots to assist in maintaining lawn or raking leaves than females (p = 0.05). Married participants indicated a higher preference for domestic robots to assist in getting information on weather/news than unmarried participants (p = 0.049). In contrast, participants who were partially dependent and fully dependent indicated a higher preference for domestic robots to assist in tasks under the personal care aspect such as shaving, bathing, washing/combing hair, getting dressed, walking, and brushing teeth (p &lt; 0.001), comparing to participants who were physically independent.

Conclusion

This study provides insight for manufacturers to develop domestic robots with specific capabilities which are important to support elders’ living in the community. Moreover, it helps the care providers to identify domestic robots with the required capabilities that meet elders’ specific preferences.

1040 VALIDATION OF THE CHINESE VERSION OF THE ASSISTANCE PREFERENCE CHECKLIST

Introduction

Domestic robots have great potential to be developed as a useful and supportive device for elders in domestic setting. To achieve the intended purpose, the designs of domestic robots should make reference to elders’ preferences. The Assistance Preference Checklist is developed to assess elders’ preferences on receiving assistance from domestic robots. It comprises of 48 home-based task under six categories including personal care, leisure activities, health assistance, chores, information management, and manipulating objects. Altogether, these tasks are considered important for the elders to fulfil their general health needs and maintain their homes. The Assistance Preference Checklist is valid and reliable. To adapt it in the Chinese population, the Assistance Preference Checklist has been translated from English to Chinese according to the standard translation model. This study aims to validate the Chinese version of the Assistance Preference Checklist (the checklist).

Method

This was a validation study. Semantic and content equivalence of the checklist was evaluated by an expert panel (five academic specialized on instrument validation or translation and 15 nurses specialized on geriatrics). Content validity of the checklist was assessed by another expert panel (one academic specialized on instrument validation and two nurses specialized on geriatrics). Internal consistency of the checklist was determined by Cronbach's method on a convenience sample of 50 Chinese-speaking elders in Hong Kong.

Results

The checklist demonstrated good semantic and content equivalence with the original English version. The experts agreed that it was appropriately translated. The checklist demonstrated good content validity by having a content validity index of 1.00. Additionally, the checklist reported satisfactory internal consistency by having a Cronbach's alpha of 0.95.

Conclusion

The Chinese version of the Assistance Preference Checklist is a useful instrument for assessing elders’ preferences on receiving assistance from domestic robots. Findings provide evidence on its validity and reliability.

1047 VALIDATION OF THE CHINESE VERSION OF THE KATZ INDEX OF INDEPENDENCE IN ACTIVITIES OF DAILY LIVING

Introduction

Among the instruments that measure an elder’s functional dependence level, the Katz Index of Independence in Activities of Daily Living has the advantages of being neutral, easy to use, valid, and reliable. It is a six-item instrument rating an elder’s functional dependence level in performing activities of daily living, including bathing, dressing, toileting, transferring, continence, and feeding. Each item can be rated nominally as 1 (does not require assistance to finish the activity) or 0 (requires assistance to finish the activity). By summing the score of the six items, the functional dependence level of an elder can be classified as independent (6 points), partially dependent (3–5 points), or dependent (&lt; 2 points). The instrument has been translated from English to Chinese through forward and backward translation. This study aims to validate the Chinese version of the Katz Index of Independence in Activities of Daily Living (Katz ADL-Chinese).

Method

This was a validation study. The Katz ADL-Chinese was examined by an expert panel (one academic specialized on instrument validation, four academic specialized on translation, fifteen nurses specialized on geriatrics) for its semantic and content equivalence with the original English version. It was evaluated by another expert panel (one academic specialized on instrument validation and two nurses specialized on geriatrics) for its content validity. Moreover, it was tested and re-tested at 1-week interval on 30 Chinese-speaking elders in Hong Kong.

Results

Good result was achieved on the testing for semantic and content equivalence. All experts confirmed that the Katz ADL-Chinese was appropriately translated. Good content validity was observed. The context validity index at item-level and scale-level was 1.00, respectively. Good stability was observed as well. The test–retest reliability coefficient was 0.85.

Azidothymidine Downregulates Insulin-Like Growth Factor-1 Induced Lipogenesis by Suppressing Mitochondrial Biogenesis and Mitophagy in Immortalized Human Sebocytes

Background

Increased sebum secretion is considered the main causative factor in the pathogenesis of acne. There is an unmet pharmacological need for a novel drug that can control sebum production with a favorable adverse effect profile.

Objective

To investigate the effect of azidothymidine on lipid synthesis in sebocytes and to identify the underlying mechanism of the inhibitory effect of azidothymidine on insulinlike growth factor (IGF)-1-induced lipid synthesis in sebocytes.

Methods

Immortalized human sebocytes were used for the analysis. Thin-layer chromatography (TLC) and Oil Red O staining were performed to evaluate lipid synthesis in the sebocytes. The differentiation, lipid synthesis, mitochondrial biogenesis, and mitophagy in sebocytes were investigated.

Results

TLC and Oil Red O staining revealed that azidothymidine reduced IGF-1 induced lipid synthesis in the immortalized human sebocytes. Azidothymidine also reduced IGF-1-induced expression of transcriptional factors and enzymes involved in sebocyte differentiation and lipid synthesis, respectively. Moreover, we found that IGF-1 upregulated the levels of peroxisome proliferator-activated receptorgamma coactivator-1α, LC-3B, p62, and Parkin, major regulators of mitochondrial biogenesis and mitophagy in immortalized human sebocytes. In contrast, azidothymidine inhibited IGF-1 induced mitochondrial biogenesis and mitophagy in the sebocytes.

Conclusion

These results suggest that azidothymidine downregulates IGF-1-induced lipogenesis by dysregulating the quality of mitochondria through suppression of mitochondrial biogenesis and mitophagy in immortalized human sebocytes. Our study provides early evidence that azidothymidine may be an effective candidate for a new pharmacological agent for controlling lipogenesis in sebocytes.

Persistent expression of interleukin-17 and downstream effector cytokines in recalcitrant psoriatic lesions after ustekinumab treatment

The interleukin (IL)-23/T-helper (Th)17 axis is considered central to the pathogenesis of psoriasis, with IL-36γ considered a marker for histological differential diagnosis. However, expression data regarding key cytokines in the pathogenesis of psoriasis, as well as data on the effects of IL-23 inhibition on downstream cytokines in human psoriatic skin, are limited. We investigated the expression profile of key cytokines and the effect of ustekinumab (UST) on cytokine expression in human psoriatic tissue. Tumor necrosis factor (TNF)-α, IL-23, IL-17A, and IL-22 were highly expressed in the epidermis, dermal papillae, and upper dermis in patients with psoriasis compared with controls; IL-36γ was strongly expressed in the upper epidermis. Compared with the untreated group, expression intensity and area of IL-23 were significantly decreased in the UST group; expression areas of TNF-α, IL-17A, IL-22, and IL-36γ did not differ. This study identified the distribution and quantitative expression levels of key cytokines in psoriatic lesions and demonstrated that only IL-23 was downregulated without blocking downstream effector cytokines in recalcitrant psoriatic lesions during UST treatment. Our results suggest that, although IL-23 is inhibited, the persistent expression of IL-17 through an alternative pathway maintains the vicious cycle of the TNF-α/IL-23/IL-17 axis with IL-36γ, inducing refractory psoriatic lesions in patients with well-controlled psoriasis.

Predictor of Subungual Melanoma against Benign Longitudinal Melanonychia: A Retrospective Cohort Study from Korea

Background

Longitudinal melanonychia (LM) is a common clinical finding. Most cases of LM are benign, and a wait-and-see approach is preferred in the management of this condition. Nevertheless, it is important for clinicians to distinguish subungual melanoma (SUM) from other benign LMs.

Objective

To evaluate the demographic and clinicopathologic characteristics of LM in the Korean population and to identify the predictor of SUM against other benign conditions.

Methods

This was a single-center retrospective cohort study including patients who underwent nail biopsy for LM from January 2000 to May 2019. To identify the predictor of SUM, receiver operating characteristic (ROC) analyses was performed.

Results

A total of 68 cases of biopsy-proven LM were included in the analysis. Among the 68 cases, 8 were SUM. In univariable analysis, patients diagnosed with SUM were older (p=0.035) and had a longer disease duration (p=0.004). They also showed multicolor pigmentation of LM (p=0.022), a larger width of LM (p<0.001), and associated nail plate dystrophy (p=0.010) than patients diagnosed with benign conditions. In multivariable logistic regression, width of LM showed statistical significance (odds ratio, 1.083; 95% confidence interval, 1.018~1.153). ROC analysis suggested that an LM width >28% of the whole nail was the predictor of SUM (area under the curve=0.883; p<0.001).

Conclusion

SUM has distinct demographic and clinical features. The width of LM can predict SUM against other benign LMs.

The long-term risk of lymphoma and skin cancer did not increase after topical calcineurin inhibitor use and phototherapy in a cohort of 25,694 patients with vitiligo

BACKGROUND

Topical calcineurin inhibitors have been used to treat vitiligo, either alone or in combination with phototherapy; however, the long-term safety of these agents remains controversial.

OBJECTIVE

To investigate the risk of lymphoma and skin cancer in vitiligo patients who received topical calcineurin inhibitors or phototherapy.

METHODS

A multicenter retrospective cohort study of 25,694 vitiligo patients who received topical calcineurin inhibitors or phototherapy for 6 weeks or more between 2001 and 2019 was performed. Cumulative doses of topical calcineurin inhibitors and total phototherapy sessions were determined. Outcomes were the development of lymphoma or skin cancer after enrollment, confirmed through chart review and pathology reports.

RESULTS

During 95,203 person-years, 13 cases of lymphoma, 22 of actinic keratosis, 15 of nonmelanoma skin cancer, and 5 of melanoma were observed. The risk of lymphoma and skin cancer was not significantly increased by topical calcineurin inhibitor dose or phototherapy sessions. The interaction between the topical calcineurin inhibitors and phototherapy was not associated with an increased risk of skin cancer.

LIMITATIONS

Retrospective study, individual follow-up duration less than 4 years, and no adjustment for comorbidities and medication history. Not generalizable to other races.

CONCLUSION

The long-term risk of skin cancer or lymphoma was not associated with the use of topical calcineurin inhibitors, phototherapy, and both treatments in combination in patients with vitiligo.

Evaluation for Skin Cancer and Precancer in Patients With Vitiligo Treated With Long-term Narrowband UV-B Phototherapy

Importance

Narrowband UV-B (NBUVB) phototherapy has been the mainstay in the treatment of vitiligo, but its long-term safety in terms of photocarcinogenesis has not been established.

Objectives

To investigate the risks of skin cancer and precancerous lesions among patients with vitiligo undergoing NBUVB phototherapy, based on the number of NBUVB phototherapy sessions.

Design, Setting, and Participants

This nationwide population-based retrospective cohort study enrolled 60 321 patients with vitiligo 20 years or older between January 1, 2007, and December 31, 2017. Patients and outcomes were identified through nationwide cohort data from the Korean national health insurance claims database, and frequency matching by age and sex was performed.

Exposures

The number of phototherapy sessions each patient received between 2008 and 2017. Patients were classified into 5 groups according to the number of phototherapy sessions (0 sessions, 20 105 patients; 1-49 sessions, 20 106 patients; 50-99 sessions, 9702 patients; 100-199 sessions, 6226 patients; and ≥200 sessions, 4182 patients). We also identifed patients who underwent at least 500 phototherapy sessions (717 patients).

Main Outcomes and Measures

Primary outcomes were the development of actinic keratosis, Bowen disease, nonmelanoma skin cancer, or melanoma after enrollment.

Results

Among the 60 321 patients with vitiligo in this study (33 617 women; mean [SD] age, 50.2 [14.9] years), the risks of Bowen disease (<50 sessions of phototherapy: hazard ratio [HR], 0.289 [95% CI, 0.060-1.392]; 50-99 sessions: HR, 0.603 [95% CI, 0.125-2.904]; 100-199 sessions: HR, 1.273 [95% CI, 0.329-4.924]; ≥200 sessions: HR, 1.021 [95% CI, 0.212-4.919]), nonmelanoma skin cancer (<50 sessions: HR, 0.914 [95% CI, 0.533-1.567]; 50-99 sessions: HR, 0.765 [95% CI, 0.372-1.576]; 100-199 sessions: HR, 0.960 [95% CI, 0.453-2.034]; ≥200 sessions: HR, 0.905 [95% CI, 0.395-2.073]), and melanoma (<50 sessions: HR, 0.660 [95% CI, 0.286-1.526]; 50-99 sessions: HR, 0.907 [95% CI, 0.348-2.362]; 100-199 sessions: HR, 0.648 [95% CI, 0.186-2.255]; ≥200 sessions: HR, 0.539 [95% CI, 0.122-2.374]) did not increase after phototherapy. The risk of actinic keratosis increased significantly for those who had undergone 200 or more NBUVB phototherapy sessions (HR, 2.269 [95% CI, 1.530-3.365]). A total of 717 patients with vitiligo underwent at least 500 sessions of NBUVB phototherapy; their risks of nonmelanoma skin cancer and melanoma were no greater than those of the patients who did not undergo NBUVB phototherapy (nonmelanoma skin cancer: HR, 0.563 [95% CI, 0.076-4.142]; melanoma: HR, not applicable).

Conclusions and Relevance

Our results suggest that long-term NBUVB phototherapy is not associated with an increased risk of skin cancer in patients with vitiligo and that NBUVB phototherapy may be considered a safe treatment.

Non-surgical treatment of vitiligo

Vitiligo is an acquired depigmenting skin disorder that affects 0.5% to 2% of the population. Skin lesions from vitiligo, white macules and patches on the skin, can pose a substantial psychological burdencan, causing a significant decrease in one’s quality of life. Recent basic and clinical studies have found that vitiligo is an autoimmune disorder, mediated by CD8+ T-cell and interferon-γ-mediated cytokine/chemokines. Although no treatment modality presents a complete cure for vitiligo, current treatment modalities have a modest effect on vitiligo by reversing the disease’s progression, inducing its stabilization, and promoting melanocyte regeneration. Current non-surgical treatment modalities include topical corticosteroids, topical calcineurin inhibitors, systemic corticosteroids, and phototherapy such as narrowband ultraviolet B phototherapy and excimer laser. In addition, clinicians have used and combined non-surgical treatment modalities based on the activity and extent of vitiligo. Moreover, considering the high risk of vitiligo relapse, maintenance therapy for re-pigmented lesions has also been introduced. Lastly, based on the results of recent translational research, new and emerging treatment modalities have been introduced, such as Janus kinase inhibitors. This review presents an overview of the current non-surgical treatment modalities for vitiligo and discusses emerging treatments.

Possible Role of Lysine Demethylase 2A in the Pathophysiology of Psoriasis

Background

Psoriasis is a common chronic inflammatory skin disease. The development of psoriasis is dependent on many intercellular events such as innate immunity and T cell-mediated inflammation. Furthermore, genetic factors are strongly implicated in the pathophysiology of psoriasis. Although a variety of susceptible genes are identified, it is likely that many important genes remain undisclosed.

Objective

The aim of this study is to investigate the possible role of lysine demethylase 2A (KDM2A) in the pathophysiology of psoriasis.

Methods

We examined the expression of KDM2A using a well established imiquimod-induced psoriasiform dermatitis model.

Results

Immunohistochemistry analysis showed that expression of KDM2A was increased in imiquimod-induced psoriasiform dermatitis. Consistent with this result, KDM2A level was markedly increased in the epidermis of psoriatic patient. When keratinocytes were stimulated with TLR3 agonist poly(I:C), KDM2A was increased at both the mRNA and protein levels. Poly(I:C) increased the expression of psoriasis-related cytokines including tumor necrosis factor-α, interleukin-8, and CCL20, and KDM2A inhibitor daminozide enhanced the poly(I:C)-induced cytokine expression. Finally, topical co-application of imiquimod and daminozide exacerbated the imiquimod-induced psoriasiform dermatitis.

Conclusion

Together, these results suggest that KDM2A is increased to negatively regulate the inflammatory reaction of epidermal keratinocytes in psoriasis.

Effects of a Mindfulness-based Intervention on diurnal cortisol pattern in disadvantaged families: A randomized controlled trial

OBJECTIVE

The present study examined the psychophysiological effects of Family-based Mindfulness Intervention (FBMI) on children and parents from disadvantaged families.

METHODS

This randomized controlled trial recruited parents and their children from 51 disadvantaged families in Hong Kong and randomized them into FBMI (n = 26) and waitlist control (n = 25) groups. The parent intervention included 6 sessions and the child intervention included 8 sessions with 2 half-hour joint programs. Both interventions lasted 9 hours in total each. All participants completed four salivary cortisol measures after wakeup, before lunchtime, late-afternoon, and before sleep at baseline and end of the intervention. The diurnal cortisol pattern was summarized by the morning cortisol, evening cortisol, mean cortisol, and diurnal cortisol slope.

RESULTS

Compared to the control group, children in the FBMI group showed significant increases in morning cortisol (d = 0.50, p =  0.03) and significant decreases in diurnal cortisol slopes (d = 0.50, p =  0.04) at the end of intervention. Parents in the FBMI group displayed significant decreases in evening cortisol (d = 0.50, p =  0.04) compared to the control group at the end of intervention. No significant treatment effects were found on the mean cortisol.

DISCUSSION

The present findings suggest that FBMI could improve the diurnal cortisol slope and cortisol levels of the children and parents from disadvantaged families, respectively. Future studies should elucidate its potential benefits on neuroendocrine functioning.

Predictive Model for Differential Diagnosis of Inflammatory Papular Dermatoses of the Face

Background

The clinical features of inflammatory papular dermatoses of the face are very similar. Their clinical manifestations have been described on the basis of a small number of case reports and are not specific.

Objective

This study aimed to use computer-aided image analysis (CAIA) to compare the clinical features and parameters of inflammatory papular dermatoses of the face and to develop a formalized diagnostic algorithm based on the significant findings.

Methods

The study included clinicopathologically confirmed inflammatory papular dermatoses of the face: 8 cases of eosinophilic pustular folliculitis (EPF), 13 of granulomatous periorificial dermatitis-lupus miliaris disseminatus faciei (GPD-LMDF) complex, 41 of granulomatous rosacea-papulopustular rosacea complex (GR-PPR) complex, and 4 of folliculitis. Clinical features were evaluated, and area density of papular lesions was quantitatively measured with CAIA. Based on these variables, we developed a predictive model for differential diagnosis using classification and regression tree analysis.

Results

The EPF group showed lesion asymmetry and annular clusters of papules in all cases. The GPD-LMDF complex group had significantly higher periocular density. The GR-PPR complex group showed a higher area density of unilateral cheek papules and the highest total area density. According to the predictive model, 3 variables were used for differential diagnosis of the 4 disease groups, and each group was diagnosed with a predicted probability of 67%~100%.

Conclusion

We statistically confirmed the distinct clinical features of inflammatory papular dermatoses of the face and proposed a diagnostic algorithm for clinical diagnosis.

Enhancement of lipid content and inflammatory cytokine secretion in SZ95 sebocytes by palmitic acid suggests a potential link between free fatty acids and acne aggravation

A relationship between acne and free fatty acids (FFAs) has been suggested recently. However, the effects of FFAs on sebaceous glands are still largely unknown. At the same time, the role of FFAs during chronic inflammation is well established. Considering that FFAs are also a major component of sebum, it is likely that changes in FFA affect both the synthesis of sebum and the inflammatory response in sebaceous glands. In this study, we examined a hypothesis that FFAs increase the production of sebum and induce inflammation in the sebaceous glands. We found that treatment of SZ95 sebocytes with exogenously applied palmitic acid (PA), a major saturated FFA, induced a significant increase in intracellular lipid levels. Moreover, PA treatment also increased the expression and secretion of the proinflammatory cytokines in SZ95 sebocytes. We also found that Toll-like receptors were required for the inflammatory response triggered by PA. The results of our study strengthen the notion about the link between acne and FFAs and suggest the mechanism underlying this relationship. Our results serve as a foundation for future work that will explore the association between FFA and acne and pave way to the development of novel treatment options for acne.

Infection, antibiotic exposure and development of atopic dermatitis: A nationwide case-control study

Previous studies suggest an association between atopic dermatitis (AD) and exposure to microorganisms and antibiotics. However, these studies have limitations, and the sole influence on the development of AD was elusive. We performed a nationwide population-based case-control study in a Korean population to investigate the association between AD and early-life infection or antibiotic exposure. A total of 244 805 children with AD from the 2 283 601 children born between January 2010 and December 2014 and an equal number of sex- and age-matched healthy children were enrolled. A conditional logistic regression analysis showed that the episode of infection and antibiotic exposure were associated with an increased risk of AD (odds ratio [OR], 1.60; 95% confidence interval [CI], 1.58-1.63 for infection; and OR, 1.11; 95% CI, 1.09-1.13 for antibiotic exposure). A dose-dependent relationship was observed between risk for AD, the number of infection episodes and antibiotic cycles and the duration of antibiotic exposure. On further analysis using a conditional logistic model, the risk of AD was less when the antibiotics were used during the infection episode than that without the use of antibiotics, especially if the duration of the infection was short. Although our study could not consider the effect of cause or severity of infection, class of antibiotics and genetic or environmental factors of enrolled subjects, our results suggested that infection and antibiotic exposure were associated with an increased risk of AD. In addition, the results also implied that the use of antibiotics during an infection episode can decrease the risk of AD induced by the infection and that appropriate management of infections can minimize the risk of AD induced by infection or antibiotics.

Effectiveness of Transconjunctival Fat Removal and Resected Fat Grafting for Lower Eye Bag and Tear Trough Deformity

Importance

The main treatment of lower eye bags is changing from fat removal techniques to fat repositioning techniques. However, fat repositioning techniques have potential complications because of disruption of the middle lamellae, leading to contracture and shortening.

Objective

To determine whether transconjunctival fat removal followed by resected fat grafting is an effective alternative method of eye bag treatment.

Design, Setting, and Participants

This retrospective study of 229 consecutive patients who underwent transconjunctival fat removal followed by resected fat grafting from November 1, 2011, to October 31, 2017, was conducted by review of medical records from the Seoul H Dermatology Clinic in Seoul, Korea.

Main Outcomes and Measures

Comparison of patient satisfaction and modified Goldberg scores before and after surgery.

Results

A total of 229 patients (mean [SD] age, 41.24 [11.11] years; range, 20-69 years; 164 [71.6%] female) underwent transconjunctival fat removal followed by resected fat grafting. Of the 229 patients, 224 (97.8%) were satisfied with their surgical results, and major improvements were seen in the mean (SD) preoperative and postoperative scores for orbital fat prolapse (preoperative: 1.94 [0.63]; postoperative: 0.07 [0.21]), tear trough depression (preoperative: 1.61 [0.75]; postoperative: 0.33 [0.42]), skin transparency (preoperative: 1.15 [0.97]: postoperative: 0.22 [0.37]), and triangular malar mound (preoperative: 0.37 [0.61]; postoperative: 0.34 [0.58]). Although the orbicularis prominence worsened after surgery, this outcome should be interpreted as a good result for Asian patients. Skin elasticity deteriorated postoperatively.

Conclusions and Relevance

The findings suggest that transconjunctival fat removal followed by resected fat grafting is an effective and safe technique to treat lower eyelid fat herniation without increased complication rates and provides good patient and surgeon satisfaction.

Level of Evidence

4.

Tropomyosin-receptor kinase fused gene (TFG) regulates lipid production in human sebocytes

The endoplasmic reticulum (ER) is an organelle in which important cellular events such as protein synthesis and lipid production occur. Although many lipid molecules are produced in the ER, the effect of ER-organizing proteins on lipid synthesis in sebocytes has not been completely elucidated. Tropomyosin-receptor kinase fused gene (TFG) is located in ER exit sites and participates in COPII-coated vesicle formation along with many scaffold proteins, such as Sec. 13 and Sec. 16. In this study, we investigated the putative role of TFG in lipid production in sebocytes using an immortalized human sebocyte line. During IGF-1-induced lipogenesis, the level of the TFG protein was increased in a time- and dose-dependent manner. When TFG was over-expressed using recombinant adenovirus, lipid production in sebocytes was increased along with an up-regulation of the expression of lipogenic regulators, such as PPAR-γ, SREBP-1 and SCD. Conversely, down-regulation of TFG using a microRNA (miR) decreased lipid production and the expression of lipogenic regulators. Based on these data, TFG is a novel regulator of lipid synthesis in sebocytes.

Comparison of the Gut Microbiota of Centenarians in Longevity Villages of South Korea with Those of Other Age Groups

Several studies have attempted to identify factors associated with longevity and maintenance of health in centenarians. In this study, we analyzed and compared the gut microbiota of centenarians in longevity villages with the elderly and adults in the same region and urbanized towns. Fecal samples were collected from centenarians, elderly, and young adults in longevity villages, and the gut microbiota sequences of elderly and young adults in urbanized towns of Korea were obtained from public databases. The relative abundance of Firmicutes was found to be considerably higher in subjects from longevity villages than those from urbanized towns, whereas Bacteroidetes was lower. Age-related rearrangement of gut microbiota was observed in centenarians, such as reduced proportions of Faecalibacterium and Prevotella, and increased proportion of Escherichia, along with higher abundances of Akkermansia, Clostridium, Collinsella, and uncultured Christensenellaceae. Gut microbiota of centenarians in rehabilitation hospital were also different to those residing at home. These differences could be due to differences in diet patterns and living environments. In addition, phosphatidylinositol signaling system, glycosphingolipid biosynthesis, and various types of N-glycan biosynthesis were predicted to be higher in the gut microbiota of centenarians (corrected p < 0.05). These three metabolic pathways of gut microbiota can be associated with the immune status and healthy gut environment of centenarians. Although further studies are necessary to validate the function of microbiota between groups, this study provides valuable information on centenarians' gut microbiota.

A quantitative, objective method for evaluating the surgical outcomes of baggy eyelid correction using orbital gray scale analysis

BACKGROUND

Baggy lower eyelids (BLEs) are a common cosmetic problem that is treated using various methods. However, validated objective methods for evaluating the treatment are limited.

AIMS

A novel BLE correction procedure, transconjunctival fat resection, and subsequent fat grafting, was assessed using the orbital gray scale (OGS), a previously suggested objective measure for BLEs.

METHODS

All patients were evaluated using both the tear trough rating scale (TTRS), a surgeon-derived evaluation method, and OGS, an objective computer-derived assessment. Changes throughout the surgery and their relationship to clinical characteristics, as well as the association between the two measurements, were statistically analyzed.

RESULTS

A total of 50 patients who underwent surgery were analyzed. No major complications other than wrinkles were observed. All patients showed improvement in both the TTRS scores and OGS values (P < 0.05). Lateral OGS was improved to a greater extent in older patients (P < 0.05). Medial OGS change was associated with improvement of tear trough depression (P < 0.05). Lateral OGS change was related to decreased infraorbital fat herniation (P < 0.05). Total OGS change was related to improvement of both tear trough depression and fat prolapse (P < 0.05).

CONCLUSION

The total OGS change was significantly associated with improvements in tear trough depression and fat bulging. Therefore, it could be a convenient objective evaluation measure for eyelid correction procedures.

The 308-nm excimer laser treatment does not increase the risk of skin cancer in patients with vitiligo: A population-based retrospective cohort study

A 308-nm excimer laser (EL) has been widely used to treat patients with localized vitiligo. However, data are rare on the influence of EL treatment on the risks of skin cancer. To evaluate the skin cancer risks after long-term EL treatment, we performed a nationwide population-based retrospective cohort study using the Korean National Health Insurance Claims Database. A total of 5,052 patients with vitiligo were classified into three groups according to the EL treatment sessions between 2009 and 2016: no, 50-99, and 100 or more EL treatments after 2-year washout period (2007 and 2008). Using multivariable Cox proportional hazard models, we found that the risks of actinic keratosis, non-melanoma skin cancers, and melanoma did not significantly differ among the groups, respectively. In conclusion, EL treatment would not increase the risks of premalignant skin lesions and skin cancers in patients with vitiligo. Based on our results, EL is likely to be a safe treatment option for patients with localized vitiligo.

Analysis of Clinical Features and Treatment Outcomes Using 1,064-nm Nd-YAG Laser with Topical Hydroquinone in Patients with Riehl's Melanosis: A Retrospective Study in 10 Patients

Background

Hyperpigmentation on the face and neck can be a devastating psychological burden in patients with Riehl's melanosis. However, successful treatment of the disease is challenging for clinicians.

Objective

To evaluate the effectiveness and safety of low-fluence neodymium-doped yttrium aluminum garnet (Nd:YAG) laser in the treatment of Riehl's melanosis and to identify prognostic factors determining the response to laser treatment.

Methods

We enrolled 10 Korean patients with Riehl's melanosis. The patients received 10~28 treatment sessions at 3-week intervals with low-fluence Nd:YAG laser.

Results

Among all the patients, seven reached near total improvement, and two and one patient reached marked improvement and minimal improvement, respectively, after low-fluence Nd:YAG laser treatment. The mean number of needed laser treatment sessions to reach marked improvement and near total improvement was 12.1±4.0 (ranged from 6 to 17) and 14.6±4.4 (ranged from 9 to 20), respectively. A further analysis revealed the proportion of patients who reached near total improvement was higher, and the mean number of necessary laser treatment sessions to reach minimal improvement was less in patients with dark brown pigmentation compared to those with light brown pigmentation. Among all patients, three complained of guttate hypopigmentation. However, the hypopigmented lesions spontaneously improved after the interruption of the treatment.

Conclusion

We found that low-fluence Nd:YAG laser is an effective and safe treatment modality for Riehl's melanosis.

Real-World Experience with Etanercept Therapy and the Switching Pattern among Korean Patients with Psoriasis after Withdrawal of Etanercept

Background

Objective

Methods

Results

Conclusion

Both Educational Lectures and Reference Photographs Are Necessary to Improve the Accuracy and Reliability of Psoriasis Area and Severity Index (PASI) Assessment: Results from Korean Nation-Wide PASI Educational Workshop

Background

Accurate assessment of the severity of psoriasis is important in daily practice and clinical studies. However, the assessment of psoriasis area and severity index (PASI) reflects the physician's experience, and thus evaluations by physicians are inherently subjective, with intra-rater and inter-rater variability.

Objective

To elucidate the effectiveness of PASI educational lectures and the use of reference photographs on the improvement of accuracy and reliability in PASI assessments and to develop effective educational programs for PASI assessments.

Methods

We performed a before-and-after comparison study during nation-wide PASI educational workshops. The participants were asked to assess the severity components of PASI (erythema, thickness, scale, and affected area) three times: in the test administered before an educational lecture, the test immediately after the lecture, and lastly the test with the use of reference photographs. The improvement of accuracy and reliability was analyzed by comparing the results of three tests.

Results

Ninety-six board-certified dermatologists and residents participated and 72 participants completed all three tests. The accuracy and reliability of the assessment of severity components of PASI increased significantly after the educational lecture and the use of reference photographs. Use of reference photographs resulted in limited improvements when the recognition of three-dimensional structures was required, such as in the assessment of thickness or scale.

Conclusion

Our study confirmed that the combination of standardized educational training and reference photographs can improve the accuracy and reliability of PASI assessments. Understanding how to evaluate three-dimensional psoriatic lesions can help with proper assessment of the severity of psoriasis.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study)

BACKGROUND

Psychological aspect and quality of life should be considered in treating patients with psoriasis.

OBJECTIVE

We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ).

RESULTS

Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental).

CONCLUSION

The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Risk Factors Affecting Adverse Effects of Cyclosporine A in a Real-World Psoriasis Treatment

Background

No study to date has focused on the changes in laboratory test results and related risk factors in patients with psoriasis treated with prolonged Cyclosporine A (CsA) therapy.

Objective

The objective of this study was to investigate the changes of laboratory values and related risk factors in patients with psoriasis treated with CsA in a real-world setting.

Methods

Records of patients with psoriasis treated with CsA at an outpatient clinic were collected, and a Cox proportional hazards regression model was used.

Results

Of the 128 patients included in this study, 28 patients (21.9%) showed laboratory test abnormalities over a mean medication period of 11.6 months. Older age (hazard ratio [HR], 1.174; 95% confidence interval [CI], 1.068~1.370; p=0.007) and pre-existing kidney disease (HR, 0.008; 95% CI, 0~0.205; p=0.001) significantly increased the risk of renal dysfunction. Male sex was the only significant risk factor for liver enzyme elevation (HR, 0.284; 95% CI, 0.081~0.784; p=0.026) and uric acid abnormality (HR, 0.048; 95% CI, 0~0.372; p=0.046).

Conclusion

This is an in-depth analysis of laboratory changes and related risk factors in patients with psoriasis treated with CsA. Liver is the most commonly affected organ of CsA toxicity. Older age, male sex, and presence of kidney disease were risk factors associated with laboratory abnormality during CsA treatment.

Economic Burden Can Be the Major Determining Factor Resulting in Short-Term Intermittent and Repetitive Ustekinumab Treatment for Moderate-to-Severe Psoriasis

Background

The continuous use of biologic agents in the treatment of psoriasis has been reported to result in successful and sustained therapeutic effects and safety. However, some patients choose intermittent and repetitive treatment.

Objective

To determine the factors for selecting intermittent and repetitive ustekinumab treatment for the management of psoriasis.

Methods

From January 2011 to October 2016, we enrolled 30 psoriasis patients who discontinued ustekinumab treatment and were followed up for psoriasis treatment. We reviewed data regarding patients' clinical characteristics and the treatment they received, and investigated the factors for selecting intermittent treatment.

Results

A total of 52 ustekinumab treatment periods were administered to the 30 patients. Of the 52 treatment periods, 34.6% were covered by insurance and 82.4% were discontinued after sufficient improvement had been made or at the patient's request. Further analysis comparing the first and second ustekinumab treatments revealed that the patients who used ustekinumab in second treatment were more likely to be insured. In addition, the rate of patients reaching psoriasis area and severity index (PASI)75 and PASI90 was similar between the first and subsequent ustekinumab treatments.

Conclusion

We found that the patients who used ustekinumab intermittently were those who were satisfied with the outcome of ustekinumab treatment but could not afford the treatment. These results suggested that economic burden can be a factor for the patients' choice of short-term intermittent treatment. The expansion of insurance coverage can increase the effectiveness of, and patients' satisfaction with, the management of psoriasis.

Economic Factors as Major Determinants of Ustekinumab Drug Survival of Patients with Chronic Plaque Psoriasis in Korea

Background

Drug survival, defined as the time until discontinuation, is a parameter reflecting real-world therapeutic effectiveness. Few studies have examined the influence of economic factors on the drug survival of biologic agents for psoriasis, particularly in Asian countries.

Objective

To determine the drug survival for ustekinumab in real-life settings and investigate the factors affecting drug survival for psoriasis patients in Korea.

Methods

We evaluated 98 psoriasis patients who were treated with ustekinumab at a single center. We analyzed the efficacy and drug survival of ustekinumab. Cox proportional hazard analysis and competing risk regression analysis were performed to reveal the factors affecting the drug survival of ustekinumab.

Results

The overall mean drug survival was 1,596 days (95% confidence interval [CI], 904~2,288). Among the 39 cessations of ustekinumab treatment, 9 (23.1%) patients discontinued treatment after experiencing satisfactory results. Multivariate Cox proportional hazard analysis revealed that paying on patients' own expense was the major predictor for the discontinuation of ustekinumab (hazard ratio [HR], 9.696; 95% CI, 4.088~22.998). Competing risk regression analysis modeling of discontinuation because of factors other than satisfaction of an event also revealed that ustekinumab treatment at the patient's expense (HR, 4.138; 95% CI, 1.684~10.168) was a predictor of discontinuation rather than satisfaction.

Conclusion

The results of our study revealed that the cost of biologics treatment affects the drug survival of ustekinumab and suggested that economic factors affect the drug survival of ustekinumab treatment in Korea.

Epidemiology and comorbidities of patients with chronic urticaria in Korea: A nationwide population-based study

Few population-based studies have focused on the epidemiology and comorbidities of chronic urticaria (CU) or chronic spontaneous urticaria (CSU). The objective of this study was to obtain information on the epidemiology and comorbidities associated with CU and CSU in Korea. We conducted a cross-sectional analysis using a national health insurance database. An algorithm based on the International Classification of Diseases, 10th revision, was used for the identification of patients with CU and CSU, and an age-sex adjusted logistic regression model was used to assess the risk of comorbidities in these patients. The average annual prevalence rates of CU and CSU during the 4-year period between 2010 and 2013 were 3.08% and 1.40%, respectively. The prevalence rates of CU and CSU were higher in women than men (1:1.39 and 1:1.34, respectively) and peaked at 0-9 and 70-79 years, respectively. After adjustment for age and sex, the patients with CU and CSU were found to have a significantly higher prevalence rate of CU/CSU-related diseases, compared with those without CU (mean adjusted odds ratio, 8.46; 95% confidence interval, 8.10-8.83). Allergic rhinitis, drug allergies, asthma, thyroid diseases and cancers were the most common comorbidities. Stomach, thyroid, liver and prostate cancers were the most prevalent cancers. This study provides large epidemiological data on the prevalence rates of CU and CSU, and their comorbidities, in Korea. Patients with CU and CSU impose a higher burden, in terms of specific comorbidities, than those without CU.

The pathogenic role of interleukin-22 and its receptor during UVB-induced skin inflammation

Recent studies show that IL-22, a cytokine produced by activated CD4+ T cells and NK cells, plays a pathogenic role in acute and chronic skin diseases. While IL-22 is produced by immune cells, the expression of IL-22Rα, the functional subunit of IL-22R, is mostly restricted to non-hematopoietic cells in organs such as the skin and pancreas. Although it is well known that ultraviolet B (UVB) radiation induces skin inflammation, there have been no reports regarding the effect of UVB on the expression of IL-22Rα. This study investigated IL-22Rα expression and IL-22-mediated proliferation and pro-inflammatory cytokine production by UVB-irradiated keratinocytes. IL-22Rα was increased in HaCaT and primary human keratinocytes after UVB irradiation through the translocation of IL-22Rα from the cytosol to the membrane. This increase in the expression of IL-22Rα was mediated by the PI3K/Akt pathway. Moreover, the suppression of keratinocyte proliferation by UVB irradiation was inhibited by treatment with IL-22. At the same time, IL-22 increased the production of IL-1α, IL-6, and IL-18 in UVB-irradiated HaCaT cells and primary human keratinocytes. Finally, IL-22Rα expression was increased in UVB-irradiated human and mouse skin by immunohistochemistry. The increased expression of IL-22Rα therefore promotes keratinocyte proliferation and pro-inflammatory cytokine production during UVB-induced skin inflammation, suggesting that UVB facilitates skin inflammation by increasing the responsiveness of keratinocytes to IL-22. This study provides a new insight into UVB-induced skin inflammation and the regulation of related inflammatory skin diseases.