Beyond diagnostic artefact: structural stigma, epistemic injustice, and iatrogenic harm in the CPTSD–BPD debate (Response to D’agostino et al., 2026)

Debates concerning the relationship between complex post-traumatic stress disorder (CPTSD) and borderline personality disorder (BPD) are often framed as questions of diagnostic overlap or nosological artefact. This commentary argues that such framings are incomplete because they treat stigma as incidental and overlook the structural, epistemic, and iatrogenic harms associated with the BPD construct. Drawing on lived experience research, analyses of epistemic injustice, and evidence of harm arising from standard treatments such as dialectical behaviour therapy, I argue that BPD functions as a credibility-damaging and identity-eroding diagnosis rather than a neutral clinical descriptor. I further situate BPD within psychiatry’s historical regulation of gender and sexual nonconformity, highlighting its disproportionate impact on marginalised populations. Any meaningful discussion of CPTSD–BPD differentiation must therefore move beyond symptom overlap to address power, harm, and whose knowledge is permitted to shape psychiatric classification.