Alexithymia and Somatization in General Population

Objective: Even though the association between alexithymia and somatization seems plausible according to several studies with selected populations, it has not been verified in carefully controlled and nationally representative population studies. We conducted such a study to find out whether alexithymia is associated with somatization at population level. Methods: This study was a part of the Finnish Health 2000 Study. The nationally representative sample comprised 5129 subjects aged 30 to 97 years. Alexithymia was measured with the 20-item Toronto Alexithymia Scale (TAS-20) and somatic symptom reporting with the 12-item somatization scale derived from the Hopkins Symptom Checklist. Sociodemographic and health-related variables, including depressive and anxiety disorders, and physician verified somatic diagnoses, were treated as confounders in multivariate analyses. Results: Alexithymia was associated with somatization independently of somatic diseases, depression and anxiety and confounding sociodemographic variables. The TAS-20 factor scale “Difficulties Identifying Feelings” was the strongest common denominator between alexithymia and somatization. Conclusions: This was the first time the independent association between alexithymia and somatization was established in a large, nationally representative nonclinical sample of both young and old adults with and without mental disorders and somatic diseases. TAS-20 = 20-item version of the Toronto Alexithymia Scale; DIF = difficulties identifying feelings; DDF = difficulties describing feelings; EOT = externally orientated thinking; SCL-90 = Hopkins Symptom Checklist; SCL SOM = 12-item somatization scale derived from SCL-90; M-CIDI = Munich version of the Composite International Diagnostic Interview; ICD-10 = International Statistical Classification of Diseases and Related Health Problems, 10th Revision; DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th edition; SEM = structural equation modeling.