Brain‐derived neurotrophic factor (BDNF) levels in panic disorder: A systematic review and meta‐analysis

Abstract Background The existing literature on the association between brain‐derived neurotrophic factor (BDNF) protein levels and panic disorder presents inconsistent findings. This systematic review and meta‐analysis aim to synthesize the available evidence and determine the overall effect of BDNF protein levels in individuals diagnosed with panic disorder. Methods A comprehensive literature search was conducted using electronic databases (PubMed, Embase, Scopus, PsycINFO, and Web of Science) from inception to April 21, 2023. The search strategy included relevant keywords and medical subject headings terms related to BDNF, panic disorder, and protein levels. A random‐effects model was used for the meta‐analysis, and subgroup analyses were performed to explore heterogeneity. Publication bias was assessed using funnel plots and statistical tests. Results A total of 12 studies met the inclusion criteria. The meta‐analysis demonstrated a significant decrease in BDNF protein levels in individuals with panic disorder (SMD = −.53, 95% CI: −1.02 to −.04, p