QTc dispersion and interval changes in drug-free borderline personality disorder adolescents

Emotional instability and dysregulation represent a core feature of borderline personality disorder (BPD) and abnormal patterns of sympathetic/parasympathetic activity have been repeatedly investigated in individuals with this disorder. Such abnormalities may represent the substrate for an arrhythmogenic risk that could materialize the following specific drug exposure. In this work, we decided to assess basal-corrected QT interval and dispersion (QTc and QTcd) for estimating such risk in a sample of drug-free adolescents with diagnosis of BPD. In this cross-sectional comparative study, we recruited n = 70 female adolescent BPD (14.7 +/- 1.3 years), free of medications, alcohol or recreational drugs. Furthermore, n = 70 matched female healthy controls (CTRL, 14.6 +/- 1.5 years) were enrolled. QTc and QTcd were manually assessed on a standard 12-lead ECG by a single experienced investigator who was unaware of clinical outcomes. QTcd was increased by 7 ms on average in BPD vs. CTRL (+ 18%, p = 0.03). QTc was decreased by about 15 ms on average in BPD vs. CTRL (p = 0.003). A mild correlation was found between QTc and QTcd in BPD (r = 0.25, p = 0.03) that was not present in CTRL. No correlation was found between either QTc or QTcd, and age in both groups. Mildly increased QTcd characterizes the cardiac activity regardless of drug exposure in female adolescents with BPD. This information may be of value to clinicians striving to use neuroleptic and antidepressant drugs with a lower risk of QTcd increase.