Study design: Population-based incidence cohort.
Objective: To report the incidence, timing, and course of depressive symptoms after whiplash.
Summary of background data: Evidence is conflicting about the frequency, time of onset, and course of depressive symptoms after whiplash.
Methods: Adults making an insurance claim or seeking health care for traffic-related whiplash were followed by telephone interview at 6 weeks, and 3, 6, 9, and 12 months post-injury. Depressive symptoms were assessed at baseline and at each follow-up.
Results: Of the 5,211 subjects reporting no pre-injury mental health problems, 42.3% (95% confidence interval, 40.9-43.6) developed depressive symptoms within 6 weeks of the injury, with subsequent onset in 17.8% (95% confidence interval, 16.5-19.2). Depressive symptoms were recurrent or persistent in 37.6% of those with early post-injury onset. Pre-injury mental health problems increased the risk of later onset depressive symptoms and of a recurrent or persistent course of early onset depressive symptoms.
Conclusions: Depressive symptomatology after whiplash is common, occurs early after the injury, and is often persistent or recurrent. This suggests that, like neck pain and headache, depressed symptomatology is part of the cluster of acute whiplash symptoms. Clinicians should be aware of both physical and psychologic injuries after traffic collisions.