ImportanceTwo recent meta-analyses reported a high prevalence of both anxiety and depression in patients with alopecia areata (AA), as well as a positive association of AA with anxiety and depression, without distinguishing between disorders and symptoms. Yet, depression and anxiety can manifest either as symptoms identified in questionnaires or as specific diagnoses defined by Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) or International Statistical Classification of Diseases and Related Health Problems, Tenth Revision criteria.ObjectiveTo perform a large meta-analysis separating the prevalence of depressive and anxiety disorders from that of depressive and anxiety symptoms in patients with AA.Data SourcesPubMed, ScienceDirect, the Cochrane Library, Embase, and PsycINFO databases were searched from inception through August 1, 2020.Study SelectionStudies that contained data on the prevalence of depressive or anxiety disorders or symptoms were included.Data Extraction and SynthesisThe Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guidelines were used. Pooled prevalence was calculated with a random effects model meta-analysis that took into account between- and within-study variability. Meta-regressions were used to study the association between variations in prevalence and study characteristics.Main Outcomes and MeasuresThe prevalence of depressive and anxiety disorders and symptoms in patients with AA.ResultsThirty-seven articles (29 on depression and 26 on anxiety) that met the inclusion criteria were identified. By distinguishing between disorders and symptoms, the prevalence of both depressive disorders (9%) and unspecified anxiety disorders (13%) in patients with AA was shown to be greater than that in the general population. The prevalence and odds ratio (OR) of depressive disorders (prevalence, 9%; OR, 1.38) and anxiety disorders of which each category had been specifically studied (prevalence, 7%-17%; OR, 1.51-1.69) were markedly lower than that of depressive symptoms (prevalence, 37%; OR, 2.70) and anxiety symptoms (prevalence, 34%; OR, 3.07). Meta-regressions showed that variations in prevalence were mainly associated with methodological differences between studies.Conclusions and RelevanceIn this systematic review and meta-analysis, the separate analyses showed that 7% to 17% of patients with AA had depressive or anxiety disorders that require psychiatric care, including specific medication. Additionally, more than one-third of patients had symptoms that are warning signs and that need monitoring because they can develop into disorders.