Symptom profile of persons self-reporting whiplash: a Norwegian population-based study (HUNT 2)

Abstract
The aetiology of chronic whiplash associated disorder (WAD) is unclear and the condition has been perceived both as a chronic pain disorder, based on the injury to the neck, and as a functional somatic disorder. Based on the hypothesis that chronic WAD should be perceived as a functional somatic syndrome, we compared the symptom profile of persons with chronic WAD with the profile of persons with a functional somatic disorder, and with the profile of persons with an organic pain disorder. A sample of 55,046 persons participating in a Norwegian population-based health study (HUNT 2) was divided into four study groups: chronic WAD, fibromyalgia, rheumatoid arthritis, and controls (none of these disorders). Symptoms were categorized as pain and stiffness, cardiopulmonary and gastrointestinal symptoms, and mental disorders. Odds ratios (ORs) with 95% confidence intervals (CIs) from logistic regression were used to compare the prevalence of symptoms among the groups. The chronic WAD group had a significantly higher prevalence of symptoms from all body parts, across organ systems and also mental symptoms, compared to the control group. The fibromyalgia group had an even higher prevalence of all symptoms, while the rheumatoid arthritis group showed an increase in the prevalence of particularly pain and stiffness symptoms and also a minor increase in the prevalence of other symptoms compared to the control group. We conclude that this study provide evidence in favour of the hypothesis that chronic WAD should be perceived as a functional somatic syndrome. Persons with chronic WAD had a symptom profile more similar to people with a functional somatic disorder than an organic pain disorder, consisting of a wide array of symptoms, not only predominantly pain symptoms.