Background/Objectives: Atopic dermatitis (AD) is a prevalent chronic inflammatory skin disease, but its relationship with gastric cancer (GC) remains unclear. This study aimed to investigate the association between AD and GC using a nationwide Korean database. Methods: Using the Korean National Health Insurance Service-National Sample Cohort, we conducted a nested case–control study including 10,174 GC patients and 40,696 matched controls (1:4 by age, sex, income, and region). Overlap propensity score weighting was used to control for confounders. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated via logistic regression. Results: AD was significantly associated with an increased risk of GC (adjusted OR = 1.08; 95% CI: 1.01–1.15). Subgroup analyses revealed stronger associations among individuals aged ≥ 65 years (OR = 1.12), men (OR = 1.10), rural residents (OR = 1.14), and those without comorbidities (CCI = 0, OR = 1.15). Higher risks were also observed in participants with non-allergic rhinitis (OR = 1.43) or no asthma (OR = 1.12). Conclusions: AD may be associated with an increased risk of GC in the Korean population. These findings may highlight the importance of considering dermatological conditions in the context of systemic cancer risk.
背景/目的：特应性皮炎（AD）是一种常见的慢性炎症性皮肤疾病，但其与胃癌（GC）的关系尚不明确。本研究旨在利用韩国全国性数据库探讨AD与GC之间的关联。方法：基于韩国国民健康保险服务-国家样本队列，我们开展了一项巢式病例对照研究，共纳入10,174名胃癌患者及40,696名按年龄、性别、收入和地区进行1:4匹配的对照者。采用重叠倾向评分加权法控制混杂因素，通过逻辑回归计算校正后的比值比（OR）及其95%置信区间（CI）。结果：AD与胃癌风险增加显著相关（校正后OR=1.08；95% CI：1.01–1.15）。亚组分析显示，在年龄≥65岁（OR=1.12）、男性（OR=1.10）、农村居民（OR=1.14）以及无合并症（CCI=0，OR=1.15）的个体中关联性更强。在患有非过敏性鼻炎（OR=1.43）或无哮喘（OR=1.12）的参与者中也观察到更高的风险。结论：在韩国人群中，AD可能与胃癌风险升高相关。这些发现提示，在评估全身性癌症风险时需重视皮肤疾病的潜在影响。
Beyond the Skin: Atopic Dermatitis and Increased Gastric Cancer Risk in Korea
肿瘤(癌症)患者之家