Prevalence of psychiatric disorders in sick listed chronic low back pain patients.

BACKGROUND Previous findings have shown a high degree of comorbid psychopathology in chronic low back pain (CLBP), but less is known about the broad range of comorbid psychiatric disorders. The prevalence is reported to be between 40% and 100% depending on methods being used, sample or setting. AIMS To assess the prevalence of psychiatric comorbidity in a population of CLBP patients, using a psychiatric diagnostic interview. METHODS 565 patients sick listed between 2 and 10months for unspecific LBP were included in the study. All were recruited as part of an ongoing trial in secondary care, and were assessed with the Mini-International Neuropsychiatric Interview (MINI), which is a short structured diagnostic interview for DSM-IV and ICD-10 psychiatric disorders. RESULTS The prevalence of current psychiatric disorders was 31%. The diagnoses included 19 Axis I disorders, with the most common being somatoform disorders (18%) and anxiety disorders (12%). Major depressive disorders were reported in 4%. There were no gender differences in prevalence of psychiatric disorders. CONCLUSIONS In a large population of CLBP patients, 31% fulfilled the criteria for at least one current psychiatric disorder when measured with a diagnostic interview. The diagnoses included a wide range of psychiatric disorders, with the most common being somatoform disorders (18%) and anxiety disorders (12%). The results imply that screening CLBP patients for psychiatric comorbidity in secondary care is important since psychopathology may have serious consequences for prognosis, outcome and health care utilization.