Associations of heart rate variability at early post-injury with later post-traumatic stress disorder over two years.

Background: This study examines the prospective associations between early post-injury heart rate variability (HRV) measures and post-traumatic stress disorder (PTSD) development over a two-year follow-up period.

Methods: Baseline HRV parameters were measured including the Standard Deviation of NN Intervals (SDNN), Root Mean Square of Successive Differences (RMSSD), Low Frequency (LF) and High Frequency (HF) bands, and LF/HF ratio. Socio-demographic and clinical covariates were also collected. PTSD diagnoses were assessed using CAPS-5 at 3, 6, 12, and 24 months post-baseline. Linear regression analyses evaluated the associations between HRV parameters and PTSD diagnoses.

Results: Among 538 patients analyzed, 58 (10.8 %) were diagnosed with PTSD, with prevalence rates of 8.4 % at 3 months, 6.5 % at 6 months, 4.8 % at 12 months, and 2.5 % at 24 months. Lower RMSSD and LF values predicted PTSD over two years, with significant associations at the 3- and 6-month follow-ups. Lower HF values were also significantly associated with PTSD at 3 months, findings robust after adjusting for covariates and applying Bonferroni corrections.

Conclusion: HRV measures obtained shortly after traumatic events can serve as predictive biomarkers for PTSD, particularly within the first 6 months following a physical injury.