Epidemiology of psoriasis and palmoplantar pustulosis: a nationwide study using the Japanese national claims database

Abstract

ObjectiveThe primary objective was to estimate the national prevalence of psoriasis and palmoplantar pustulosis (PPP) in Japan. Secondary objectives were to determine (1) whether psoriasis and PPP disease activity varies by season, and (2) whether disease severity is associated with concurrent diabetes mellitus, hyperlipidaemia and hypertension.SettingsPatients with a psoriasis or PPP diagnosis code between April 2010 and March 2011 were identified using a Japanese national database.Participants565 903 patients with psoriasis or PPP were identified. No patient was excluded.Primary and secondary outcome measuresNational prevalence was calculated using census data. We estimated the difference in the proportion of patients who used healthcare services, as a proxy for disease activity, between the hot and cold seasons and the difference in the standardised prevalence of comorbidities between severe and mild disease. The measures were estimated separately for the two broad disease categories of psoriasis and PPP but not in all patients as planned because the two disease categories had major differences.ResultsThe national prevalence of psoriasis and PPP was 0.34% (95% CI 0.34% to 0.34%) and 0.12% (0.12% to 0.12%), respectively. The difference in the proportion of patients who used healthcare services in the hot compared to the cold season was −0.3% (−0.5% to −0.1%) for psoriasis and 10.0% (9.8% to 10.3%) for PPP. The difference in the standardised prevalence between severe and mild psoriasis was 3.1% (2.7% to 3.4%), 3.2% (2.8% to 3.6%) and 5.1% (4.7% to 5.6%) for concurrent diabetes mellitus, hyperlipidaemia and hypertension, respectively. No significant difference in the prevalence of comorbidity was observed for PPP.ConclusionsThe national prevalence, seasonal variation in disease activity and prevalence of comorbidities in Japanese patients with psoriasis and PPP estimated in this descriptive study may be used as basic information for future studies.

The Asian atopic dermatitis phenotype combines features of atopic dermatitis and psoriasis with increased TH17 polarization

“…Interestingly, psoriasis has a very low frequency in Asia, whereas AD presents a much higher frequency (approximately 0.5% vs 7% to 10% of adults). [19][20][21]73 In terms of molecular immunology, the T H 17 axis appears to be ''missing'' in Asia as we currently classify these polar diseases. Our report classifies Asian AD as a mixed phenotype between AD and psoriasis, harboring an intermediate cytokine profile of both diseases.…”

Cutting Edge: PD-1 Regulates Imiquimod-Induced Psoriasiform Dermatitis through Inhibition of IL-17A Expression by Innate γδ-Low T Cells

“…Interestingly, ~3% of melanoma patients treated in Japan with nivolumab developed a psoriasiform dermatitis (PsD) (4). Given that the estimated prevalence of psoriasis in general Japanese populations is only 0.3% (5), treatment with a PD-1 antagonist resulted in a dramatic increase of a psoriasis-like skin eruption in Japanese patients.…”

Psoríase pustulosa palmoplantar na infância: um relato de caso

“…No estudo realizado por Kubota et al de 2015 3 , que utilizou a base de dados Nacional do Japão para estimar a prevalência Nacional de psoríase e PPP no país, foi encontrada prevalência de 0,12% para PPP, sendo que desses apenas 1,75% tinham idade entre 0 a 19 anos, indicando a raridade da doença em crianças. O estudo revelou ainda sazonalidade nas exacerbações, também observada na paciente descrita pelo presente relato, em que a doença parece ter períodos de exacerbações mais frequentes em épocas mais quentes, em concordância com estudos que referem que a doença é mais comum em localizações com clima quente e úmido 5,6 .…”

“…De ocorrência universal e prevalência nos EUA e Europa entre 2 a 4% 3 , estima-se que afeta cerca de 1% da população brasileira 1 . Na população pediátrica a prevalência estimada varia de 0,55% a 1,4% 4 .…”