Widespread pain following whiplash-associated disorders: incidence, course, and risk factors.

Abstract

To investigate the incidence and course of widespread pain (WP) subsequent to localized pain in subjects with whiplash-associated disorders (WAD); and to investigate the influence of depressive symptoms, neck pain intensity, number of whiplash-associated symptoms, and number of painful body areas on such conditions. From a large prospective cohort of injury claimants who reported WAD after motor vehicle collision (MVC; n = 7462), we identified a subgroup with only localized head/neck/back pain, and who responded to one or more followup questionnaires mailed at 6 weeks and 4, 6, and 12 months after the MVC (n = 266). Pain drawings were distributed at the followup, and we defined WP as having 9 or more painful areas, including posterior neck, at any of these occasions. Depressive symptoms were assessed with the Center for Epidemiological Studies Depression Scale and pain intensity with on a visual analog scale (VAS). The cumulative incidence of WP was 21%, and it occurred early after the injury. Continuous WP over the 12 months was rare. The odds for developing WP were greater in those with depressive symptoms (OR 3.2, 95% CI 1.6-6.3), VAS pain intensity 55-100 (OR 3.2, 95% CI 1.3-8.0), reporting > or = 3 pain-associated symptoms (OR 1.9, 95% CI 0.9-3.8), and those reporting 4 or 5 painful body areas (OR 2.6, 95% CI 1.3-5.4). WP occurred early in the course. Even though the cumulative incidence was 21%, continuous WP was rare. Subjects with WAD who report early depressive symptoms and more severe neck injury symptoms are at risk of developing WP after MVC.