Association between iron deficiency and telogen effluvium: a systematic review and meta- analysis

Abstract

Iron deficiency has been associated with telogen effluvium, but currently, the data regarding their association are conflicting. To derive a more precise estimation of this association, we performed a systematic review and meta-analysis to investigate serum ferritin level, serum iron level, and prevalence of ferritin deficiency in all published studies. Databases including PubMed, Google Scholar, Offshore Vessel Inspection Database, and Cochrane Library, were systematically searched. The association was assessed using standardized mean differences, odds ratios, and 95% confidence intervals. Statistical analysis was performed using Review Manager version 5.4.1. A total of 20 studies were identified. The results showed that in patients with telogen effluvium, including those with acute and chronic telogen effluvium, serum iron and serum ferritin levels were lower than those in the normal population. There was no significant difference in serum ferritin and iron levels between patients with acute and chronic telogen effluvium. In patients with chronic telogen effluvium, the prevalence of ferritin deficiency was higher than that in the general population when ferritin levels were 20 ng/dl and 30 ng/dl as the threshold for the diagnosis of iron deficiency. This meta-analysis revealed that iron deficiency is associated with telogen effluvium and clarified the critical serum ferritin level for defining iron deficiency in patients with telogen effluvium.