[Formula: see text]Persistent post-concussion symptoms in children: pre-injury social difficulties and acute stress reaction as risk factors.

Following mild traumatic brain injury (mTBI) children usually experience one or more somatic, cognitive, and/or emotional-behavioral post-concussion symptoms (PCS). PCS may be transient, however for some children, persistent post-concussion symptoms (PPCS) might linger for months or years. Identifying risk factors for PPCS may allow earlier interventions for patients at greater risk. We examined pre-injury social difficulties and acute stress reaction as risk factors to PPCS in children. Participants were 83 children (aged 8-16) with mTBI. In a prospective follow-up, pre-injury social difficulties, 24-hours post-concussion symptoms, and acute stress reactions were tested as predictors of one-week and four-months PCS reports. Parents' reports, self-reports, and neurocognitive tests were employed. One-week PCS level was associated with acute stress, and not with 24-hours post-concussion symptoms or pre-injury social difficulties. Four-months PCS level was predicted by pre-injury social difficulties and 24-hours post-concussion symptoms, with no contribution of acute stress. Interestingly, less symptoms at 24-hour from injury were associated with a higher level of PCS at four months. Cognitive functioning at four months was predicted by acute stress, with no contribution of 24-hours post-concussion symptoms or pre-injury social difficulties. Cognitive functioning did not differ between children with and without PPCS. In conclusion, non-injury, socio-emotional factors (pre-injury social difficulties, acute stress) should be considered, alongside injury-related factors, in predicting recovery from mTBI. Pre-injury social difficulties and stress reaction to the traumatic event might pose an emotional burden and limit one's social support during recovery, thus require clinical attention in children following mTBI.