Association of Schizophrenia and Autoimmune Diseases

[Guest guest]

American Journal of Psychiatry 163:521-528, March 2006

doi: 10.1176/appi.ajp.163.3.521

© 2006 American Psychiatric Association

Association of Schizophrenia and Autoimmune Diseases: Linkage of

Danish National Registers

W. Eaton, Ph.D., Majella Byrne, Ph.D., Henrik Ewald,

Dr.Med.Sc., Ole Mors, Ph.D., Chuan-Yu Chen, Ph.D., Esben Agerbo, M.S.

and Preben Bo Mortensen, M.D., Dr.Med.Sc.

OBJECTIVE: Individuals with schizophrenia and their relatives tend to

have either higher or lower than expected prevalences of autoimmune

disorders, especially rheumatoid arthritis, celiac disease,

autoimmune thyroid diseases, and type 1 diabetes. The purpose of the

study was to estimate the association of schizophrenia with these

disorders as well as a range of other autoimmune diseases in a single

large epidemiologic study. METHOD: The Danish Psychiatric Register,

the National Patient Register, and a register with socioeconomic

information were linked to form a data file that included all 7,704

persons in Denmark diagnosed with schizophrenia from 1981 to 1998 and

their parents along with a sample of matched comparison subjects and

their parents. The data linkage required that the autoimmune disease

occur before the diagnosis of schizophrenia. RESULTS: A history of

any autoimmune disease was associated with a 45% increase in risk for

schizophrenia. Nine autoimmune disorders had higher prevalence rates

among patients with schizophrenia than among comparison subjects

(crude incidence rate ratios ranging from 1.9 to 12.5), and 12

autoimmune diseases had higher prevalence rates among parents of

schizophrenia patients than among parents of comparison subjects

(adjusted incidence rate ratios ranging from 1.3 to 3.8).

Thyrotoxicosis, celiac disease, acquired hemolytic anemia,

interstitial cystitis, and Sjögren’s syndrome had higher prevalence

rates among patients with schizophrenia than among comparison

subjects and also among family members of schizophrenia patients than

among family members of comparison subjects. CONCLUSIONS:

Schizophrenia is associated with a larger range of autoimmune

diseases than heretofore suspected. Future research on comorbidity

has the potential to advance understanding of pathogenesis of both

psychiatric and autoimmune disorders.

http://ajp.psychiatryonline.org/cgi/content/abstract/163/3/521