Prevalence of anxiety and depression in idiopathic pulmonary fibrosis: a systematic review and meta-analysis.

backgroundIdiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial lung disease. Anxiety and depression are prevalent psychiatric comorbidities among IPF patients; however, reported prevalence rates vary substantially, and a consolidated estimate is lacking. This systematic review and meta-analysis aimed to determine the global pooled prevalence of anxiety and depression in IPF patients and to explore potential sources of heterogeneity, thus providing a robust evidence base for clinical management and future research.

methodsThis study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A systematic literature search was conducted in PubMed, Web of Science, Cochrane Library, and Embase from database inception to October 23, 2025, to identify studies reporting the prevalence of anxiety or depression in patients with IPF. Two reviewers independently screened the literature, extracted data, and assessed the methodological quality of the included studies using the Joanna Briggs Institute (JBI) critical appraisal checklist. Two separate single-arm meta-analyses were performed, one for studies using International Classification of Diseases, Tenth Revision (ICD-10) criteria and one for those using screening tools (e.g., Hospital Anxiety and Depression Scale, Patient Health Questionnaire-9). Pooled prevalence estimates were calculated using a generalized linear mixed model (GLMM), with corresponding 95% confidence intervals (CIs) and 95% prediction intervals (PIs). Heterogeneity was assessed using Cochran's Q test, the I² statistic, and τ². Sensitivity analyses were conducted using the leave-one-out method and the Freeman-Tukey double arcsine transformation. Subgroup analyses were performed based on study design, geographic region, assessment tool, methodological quality, and sample size. Publication bias was evaluated using Doi plots and the LFK index.

resultsA total of 25 studies involving 78,060 IPF patients were included. Among these, 15 studies reported the prevalence of anxiety and 25 reported the prevalence of depression. Studies that did not specify the assessment tool were excluded from the meta-analysis, resulting in the inclusion of 14 studies for the anxiety meta-analysis and 18 studies for the depression meta-analysis. Quantitative analyses were performed separately for the ICD-10 group and the screening tool group. Anxiety in IPF: The pooled prevalence was 14.52% (95% CI: 8.90%-22.79%) in the ICD-10 group (2 studies), with substantial heterogeneity (τ² = 0.1599, I² = 98.9%, P < 0.001); the 95% PI was not calculated due to the small number of studies. In the screening tool group (12 studies), the pooled prevalence was 42.04% (95% CI: 25.28%-60.86%), with a 95% PI of 3.36%-93.80% and substantial heterogeneity (τ² = 1.7068, I² = 88.3%, P < 0.001). Depression in IPF: The pooled prevalence was 6.87% (95% CI: 3.23%-14.04%) in the ICD-10 group (3 studies), with a 95% PI of 0.00%-99.95% and substantial heterogeneity (τ² = 0.4853, I² = 99.8%, P < 0.001). In the screening tool group (15 studies), the pooled prevalence was 38.26% (95% CI: 24.65%-54.01%), with a 95% PI of 3.89%-90.46% and substantial heterogeneity (τ² = 1.4877, I² = 82.3%, P < 0.001). Subgroup analyses based on the screening tool group showed no statistically significant differences in pooled prevalence across study design, assessment tool, geographic region, methodological quality, or sample size (all P > 0.05). Sensitivity analyses confirmed the robustness of the pooled estimates for both anxiety and depression. Publication bias assessment revealed significant bias in the screening tool groups for both outcomes.

conclusionThe prevalence of anxiety and depression in IPF patients is substantial and is significantly influenced by the assessment tool used: estimates based on ICD-10 clinical diagnoses are substantially lower than those derived from screening tools. Therefore, future large-scale, high-quality studies employing standardized assessment tools are needed to accurately evaluate the psychiatric comorbidity burden in IPF patients, thereby providing robust evidence for the development of targeted clinical intervention strategies.

trial registrationPROSPERO; No.: CRD420251174885.