Late-onset development of psoriasis in Japan: a population-based cohort study.

BACKGROUND: Evidence of factors associated with psoriasis from large population-based cohort studies is scarce. OBJECTIVE: We aimed to explore the risk factors of late-onset psoriasis. METHODS: This study included 487,835 Japanese participants aged 40-107 years, who were followed prospectively from 2012 to 2018 using individually linked databases between annual health checkups and medical claims. RESULTS: During the study period, 2793 patients (0.57%) newly developed psoriasis; 13.8% had moderate-to-severe psoriasis. In the multivariate analysis, factors associated with psoriasis onset were age (hazard ratio [HR] 1.11 {95% confidence interval [CI]: 1.06-1.16}), male sex (HR: 1.11 [95% CI: 1.02-1.21]), body mass index (HR: 1.09 [95% CI: 1.05-1.14]), smoking (HR: 1.46 [95% CI: 1.31-1.63]), not exercising ≥1 hour per week (HR: 1.13 [95% CI: 1.05-1.22]), and gamma-glutamyl transpeptidase (HR: 1.04 [95% CI: 1.01-1.06]). When we used weight increment of ≥10 kg since the age of 20 years instead of body mass index in the multivariate model, this was also a risk factor (HR: 1.12 [95% CI: 1.04-1.21]). LIMITATIONS: This study targeted people aged >40 years, thereby narrowing the search to the risk factors of late-onset psoriasis. CONCLUSION: We showed that increasing age, male sex, body mass index, smoking, low physical activity, weight gain, and gamma-glutamyl transpeptidase are associated with late-onset development of psoriasis and revealed a relationship between liver dysfunction and psoriasis development.

Association of dry skin with intercellular lipid composition of stratum corneum after erlotinib administration.

PURPOSE: Erlotinib, an inhibitor of the epidermal growth factor receptor tyrosine kinase, causes skin disorders such as dry skin, which impairs the skin barrier function. Stratum corneum (SC) lipids play an important role in skin barrier function; therefore, this study aimed to investigate the relationship between erlotinib-related dry skin and changes in the intercellular lipid composition and structure of the SC. METHODS: Overall, 21 patients with non-small lung cancer were enrolled in this study. All patients received 150 mg/day erlotinib orally. A SC sample of each patient was collected from the inner forearm using the tape stripping method on days 0, 7, 14, 28, and 56 after erlotinib administration. The intercellular lipid components of ceramide (CER), free fatty acid (FFA), and cholesterol sulfate (CS) in samples extracted from the tape were analyzed using liquid chromatography/time-of-flight/mass spectrometry. SC samples from six healthy subjects were collected as controls on days 0, 28 and 56 and analyzed similarly. RESULTS: Although total CER and FFA levels were not changed after erlotinib administration, the levels of CER subclasses [AP] and [AH] and hydroxy FFA, which are structural components of CER subclass [A], decreased. In contrast, the CS levels increased after erlotinib administration. Moreover, higher CS levels in the SC correlated with the clinical condition of dry skin. No changes were observed in the SC lipid composition in healthy subjects. CONCLUSION: Erlotinib-related dry skin was associated with a higher CS level in the SC.