To review the available epidemiological evidence on associations between somatoform disorders with anxiety and depressive disorders.
Clinical and population-based studies have found that the co-occurrence of some types of somatoform disorders (e.g., somatization disorder, somatic-symptom-index (SSI)4,6, and pain disorder) and anxiety and depressive disorders is common. These findings may suggest either a causal relationship between these disorders or that they share some common etiological factors. For other forms of somatoform disorders, empirical evidence about co-occurrence is even thinner or not available at all, especially from non-western settings.
Some implications of how these findings, or the absence of them, can help us understand better the etiology of somatoform disorders and improve the classification of mental disorders as a whole are discussed.
DSM = Diagnostic and Statistical Manual of Mental Disorders;
DIS = Diagnostic Interview Schedule;
ECA = Epidemiological Catchment Area Program;
FGD = functional gastrointestinal disorders;
GAD = general anxiety disorder;
OR = odds ratio;
PTSD = posttraumatic stress disorder;
SSI = Somatic Symptom Index.