Burn family caregivers' distress trajectories: Latent and mixed-effects analyses

Family caregivers of burn survivors commonly experience psychological distress, yet longitudinal evidence describing heterogeneous adaptation patterns and the timing of clinically meaningful risk development remains limited.

We analyzed 256 caregivers assessed at baseline and 6-, 12-, and 24-month follow-ups. Latent class growth analysis was used to identify caregiver distress trajectories based on Depression Anxiety Stress Scales-21 total scores. Baseline demographic, injury, treatment-burden, and psychological characteristics were compared across classes, and a prespecified piecewise mixed-effects model examined whether class separation changed over follow-up. PTSD and posttraumatic growth were summarized secondarily to contextualize adaptation under distress-defined classes.

Three distress trajectories were identified: Low distress & lower burn severity and burden (n = 201, 78.5%), Moderate distress & higher treatment burden (n = 23, 9.0%), and High distress & higher burn severity (n = 32, 12.5%). In the piecewise model, the 0-6 month slope was not significant (β=-0.243/month; p = 0.459). During 6-24 months, trajectories diverged: Moderate distress & higher treatment burden worsened (β=2.111/month; p < 0.001), high distress & higher burn severity phenotype improved (β=-2.831/month; p < 0.001), and low distress & lower burn severity and burden phenotype remained relatively stable with a slight increase (β=0.372/month; p = 0.004). Findings were robust to alternative time specification and adjustment for baseline time since injury and burn severity. PTSD mirrored the distress-defined patterns, whereas posttraumatic growth showed a distinct pattern.

Caregiver distress after burn injury is heterogeneous, and clinically meaningful separation emerged during later follow-up. Later worsening was observed in the phenotype characterized by higher treatment-burden indicators, supporting sustained monitoring and tailored psychosocial support beyond early follow-up.