Loneliness in Autism and Its Association with Anxiety and Depression: A Systematic Review with Meta-Analyses

Objectives This systematic review aimed to quantify differences in loneliness levels between autistic and neurotypical samples and investigate the association between loneliness and mental health in autistic individuals. Methods Three meta-analyses were conducted. Studies were methodologically appraised using established tools. Results Overall, 39 studies were included. The majority of these achieved moderate methodological quality ratings. The primary meta-analysis (N = 23) found autistic samples reported higher loneliness compared with neurotypical samples (Hedges' g = .89). The meta-analyses on the associations between loneliness and anxiety (N = 14) and depression (N = 11) in autistic samples found significant pooled correlations (r = .29 and r = .48, respectively). Conclusions This review highlights numerous limitations within current autism and loneliness research. Nevertheless, loneliness in autism merits targeted clinical and research attention.