Background: Symptoms are common and often remain medically unexplained.
Objective: To assess 5-year symptom outcomes, determine how often symptoms remain unexplained and assess their relationship with mental disorders.
Design: Prospective cohort study.
Participants: Five hundred consecutive patients presenting to a medicine clinic with physical symptoms. MEASUREMENTS PREVISIT: Mental disorders, symptom characteristics, stress, expectations, illness worry, and functional status. Postvisit (immediately, 2 weeks, 3 months, 5 years): unmet expectations, satisfaction, symptom outcome, functional status, and stress.
Results: While most subjects (81%) experienced symptom improvement by 5 years, resolution rates were lower (56%), with 35% of symptoms remained medically unexplained. Most patients with medically unexplained symptoms (MUS) did not have a mental disorder. Mood or anxiety disorders were not associated with MUS (relative risks [RR]: 0.94, 95% confidence interval [CI]: 0.79 to 1.13), or with lower rates of symptom improvement (RR: 1.14, 95% CI: 0.60 to 2.2). In contrast, most patients with somatoform disorders had MUS and were unlikely to improve. Worse functioning (RR: 0.95, 95% CI: 0.91 to 0.99), longer duration of symptom at presentation (RR: 0.5, 95% CI: 0.28 to 0.87), illness worry at presentation (RR: 0.56, 95% CI: 0.35 to 0.89), or lack of resolution by 3 months (RR: 0.47, 95% CI: 0.26 to 0.86) reduced the likelihood of symptom improvement at 5 years.
Conclusions: More than half of patients presenting with a physical symptom resolve by 5 years, while a third remain medically unexplained. Most patients whose symptom remained unexplained had no mental disorder. While mood and anxiety disorders were not associated with MUS or worse outcomes, most patients with somatoform disorders had MUS and were unlikely to improve.