Causal relationship between trace elements and pityriasis rosea: A Mendelian randomization analysis

Pityriasis rosea (PR) represents a frequently occurring, acute, self-limiting papulosquamous disorder with complicated and undetermined pathogenesis, and there are no definite tissue markers or drug targets. Thus, the clinical treatment of this disease is challenging. Recent studies have partly unraveled correlations of trace elements with the onset and development of skin diseases. This study utilized the Mendelian randomization (MR) strategy to excavate the causality between trace elements and PR. A forward and multivariate MR analysis was implemented on trace elements and PR to infer the causal relationship between them, with inverse variance weighted (IVW) as the dominant analytical method, supplemented by other methods (heterogeneity, pleiotropy, and leave-one-out sensitivity tests) to ensure data stability. The results of MR analysis, mainly based on the IVW method, suggested a causation between vitamin A and PR and indicated vitamin A as a protective factor against PR (IVW: P = .023; odds ratio [OR] = 0.677; OR < 1; 95% confidence interval: 0.245-0.897). The multivariate MR analysis suggested that vitamin A could independently act on PR (P = .018; OR = 0.426; 95% confidence interval: 0.001-35.620). Vitamin A is causally associated with PR and serves as a protective factor against the disease, providing valuable insights for subsequent clinical diagnosis, treatment, and scientific research.