Globally, anxiety and depression are the most common psychiatric disorders that add large burdens to individuals and society; however, the mechanisms underlying these disorders are unclear. Several studies have found that eczema is a shared risk factor for both these conditions. We identified and evaluated eligible observational studies from EMBASE and PubMed. In total, 20 relevant cohort and case-control studies comprising 141,910 patients with eczema and 4,736,222 control participants fulfilled our established criteria. Information extracted included study design, location, sample size, sex distribution of cases and controls or reference cohorts, measurements of outcomes, odds ratio (OR) with 95% confidence interval (CI), and adjusted factors for exposure associated with outcome risk. The meta-analysis was performed by calculating the pooled OR with 95% CI, and heterogeneity was assessed using Cochrane Q and I2 statistics. The pooled effect showed a positive association (n = 4,896,099, OR = 1.63, 95% CI [1.42−1.88], p<0.001) between eczema and depression or anxiety, with positive associations also observed in the depression (n = 4,878,746, OR = 1.64, 95% CI [1.39−1.94], p<0.001) and anxiety (n = 4,607,597, OR = 1.68, 95% CI [1.27−2.21], p<0.001) groups. Subgroup and sensitivity analyses confirmed that these findings were stable and reliable. This study suggests that eczema is associated with an increased risk of developing depression and anxiety, which may assist clinicians in the prevention or treatment of these disorders.

BackgroundEczema characterized by itch, sleeplessness, and adverse effects on quality of life is associated with a risk of hematological malignancies. However, there is a controversy pertaining to whether this association implies a greater or lesser risk of hematological cancers. We aimed to explore the link between eczema and hematological malignancies risk.MethodsWe systematically searched PubMed and Embase databases from their inception to February 17, 2022. Two reviewers independently screened articles, extracted data and assessed study quality, respectively. The odds ratios and 95% confidence intervals (CIs) were pooled by using fixed or random-effects models.Results29 studies involving 2,521,574 participants examined the contribution of eczema to hematological malignancies. We found that eczema significantly increased the risk of Hodgkin's lymphoma (1.44; 95% CI, 1.07–1.95), myeloma (1.15; 95% CI, 1.04–1.28), and significantly decreased the risk of lymphocytic leukemia (0.91; 95% CI, 0.84–0.99); however, it is not significantly associated with Non-Hodgkin's lymphoma, and myelocytic leukemia.ConclusionEczema has been shown to be associated with the risk of hematological cancer, this association still needs to be verified in large randomized controlled trials.Systematic Review Registrationhttps://inplasy.com/, INPLASY202260097.