Epidemiology of the association between somatoform disorders and anxiety and depressive disorders : an update

OBJECTIVE: To review the available epidemiological evidence on associations between somatoform disorders with anxiety and depressive disorders. RESULTS: 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. CONCLUSION: 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.