The co-occurrence of chronic primary pain defined as pain in 1 or more anatomical regions that persists or recurs for longer than 3 months, is associated with significant emotional distress and/or significant functional disability, and symptoms are not better accounted for by another diagnosis of anxiety, and depression in children constitutes a serious health problem, also summarized under the internalising cluster. (For ease of reading, the word “children” will be used for both children and adolescents throughout the topical review.) Children with chronic pain suffer substantially more from anxiety and depression compared to healthy children, with comorbidity rates ranging between 50% and 82%.
This co-occurrence aggravates and leads to severe mental health problems (MHP; the overarching term “MHP” will be used for the presence of psychopathological symptoms or mental health disorders throughout the review17) and pain problems in adulthood. Treatment outcome is significantly worse, even in the most intensive form of treatment. Today, there are sound conceptual models accounting for the co-occurrence.