Multiple somatic symptoms in primary care: A field study for ICD-11 PHC, WHO's revised classification of mental disorders in primary care settings.

Objective: A World Health Organization (WHO) field study conducted in five countries assessed proposals for Bodily Stress Syndrome (BSS) and Health Anxiety (HA) for the Primary Health Care Version of ICD-11. BSS requires multiple somatic symptoms not caused by known physical pathology and associated with distress or dysfunction. HA involves persistent, intrusive fears of having an illness or intense preoccupation with and misinterpretation of bodily sensations. This study examined how the proposed descriptions for BSS and HA corresponded to what was observed by working primary care physicians (PCPs) in participating countries, and the relationship of BSS and HA to depressive and anxiety disorders and to disability.

Method: PCPs referred patients judged to have BSS or HA, who were then interviewed using a standardized psychiatric interview and a standardized measure of disability.

Results: Of 587 patients with BSS or HA, 70.4% were identified as having both conditions. Participants had an average of 10.9 somatic symptoms. Patients who presented somatic symptoms across multiple body systems were more disabled than patients with symptoms in a single system. Most referred patients (78.9%) had co-occurring diagnoses of depression, anxiety, or both. Anxious depression was the most common co-occurring psychological disorder, associated with the greatest disability.

Conclusion: Study results indicate the importance of assessing for mood and anxiety disorders among patients who present multiple somatic symptoms without identifiable physical pathology. Although highly co-occurring with each other and with mood and anxiety disorders, BSS and HA represent distinct constructs that correspond to important presentations in primary care.