Breath-hold time and anxiety-related vulnerability: A systematic review and meta-analysis.

Altered interoceptive processing and reduced tolerance to aversive bodily sensations are core features of anxiety disorders. Maximal voluntary breath-holding time (mvBHT) has been proposed as a simple, objective behavioral index of interoceptive tolerance. This PRISMA-guided systematic review and meta-analysis evaluated mvBHT as a performance-based marker of interoceptive tolerance in anxiety by examining whether this measure differentiates adults with anxiety disorders (AD) from healthy controls (HC), quantifying its associations with trait and state anxiety, and examining study-level moderators (sex, age, and breath-hold onset). 22 studies (N = 1263 adults) were included. Random-effects models showed that AD exhibited shorter mvBHT than HC, an effect driven by a significant medium-sized reduction in panic disorder (PD) with low heterogeneity, whereas non-PD anxiety disorders yielded a smaller, nonsignificant effect. Multilevel meta-analytic correlations indicated marginal, non-significant associations between mvBHT and trait anxiety once within-study dependence was accounted for, whereas associations with state anxiety and momentary distress assessed during or immediately after respiratory challenge were significant and consistently stronger. Meta-regressions in HC samples indicated that a higher proportion of females predicted shorter mean mvBHT, and that protocols initiating the breath-hold after inhalation yielded longer mvBHT than those initiating after exhalation. In PD samples, sex composition did not predict mvBHT, whereas breath-hold onset remained the primary study-level predictor. Overall, mvBHT reliably distinguishes clinical from non-clinical groups and tracks state anxiety and distress; trait correlations are marginal and non-significant once within-study dependence is properly modelled, supporting its utility as a performance-based behavioral marker of respiratory interoceptive tolerance.