The crossroads of polyautoimmunity;

Sjogren's syndrome sits at the intersection of autoimmune diseases.

Photo by Mike Enerio on Unsplash

Sjogren’s syndrome takes center stage again in this observational cross-sectional study on polyautoimmunity. Polyautoimmunity is when one person meets the study classification criteria for two or more autoimmune diseases.

Area of Investigation

Multiple Autoimmune Syndrome: when one person meets the study classification criteria for three or more autoimmune diseases.

Title & Authors

Sjogren’s syndrome at the crossroad of polyatuoimmunity by Amador-Patarroyo MJ, Arbelaez JG, Mantilla RD, Rodriguez-Rodriguez A, Cárdenas-Roldán J, Pineda-Tamayo R, Guarin MR, Kleine LL, Rojas-Villarraga A, Anaya JM.

Anaya has consistently authored the majority of studies I’ve found on multiple autoimmune syndrome, along with a changing cast of other authors and institutions.

Results

The study included 410 people with Sjogren’s syndrome, and found that

• 66.8% of study subjects had Sjogren’s syndrome alone.

• 32.6% of study subjects had Polyautoimmunity (when one person meets the classification criteria for two or more autoimmune diseases).

• 8.5% of patients had multiple autoimmune syndrome.

  • Study participants showed a high prevalence of 4 specific disease clusters in multiple autoimmune syndrome

    1. Sjogren’s syndrome, Autoimmune Thyroid Disease, Systemic Lupus Erythermatosus

    2. Sjogren’s syndrome, Autoimmune Thyroid Disease, Rheumatoid arthritis

    3. Sjogren’s syndrome, Systemic Lupus Erythematosus, Antiphospholipid syndrome

    4. Sjogren’s syndrome, Rheumatoid arthritis, Systemic Lupus Erythematosus

• 96.2% of study subjects were female.

Risk Factors for Polyautoimmunity

Those patients who were determined to have polyautoimmunity were found to have three associated risk factors for polyautoimmunity:

• Duration of Sjogren’s syndrome

• Current or former habitual smoker

• History of spontaneous abortion

NOT associated with risk of Polyautoimmunity

Interestingly, there were two factors the researchers investigated that were not associated with polyautoimmunity

• Specific clinical or immunological characteristics of Sjogren’s syndrome, (examples: dry mouth symptoms or autoantibodies)

• Sociodemographic factors

Why the Study Matters

These results are similar to past results, in which polyautoimmunity was found in approximately 33% of study participants with Sjogren’s syndrome. Past study results also show approximately 8% incidence of multiple autoimmune syndrome. People with a diagnosis of Sjogren’s syndrome should be aware of these associations and alert for symptoms associated with other commonly co-occurring autoimmune diseases.

Study Type

Observational cross-sectional study of 410 patients with Sjogren’s syndrome, published in 2012.

For reference, I have ranked medical study types in order of study types that are least likely to be affected by hidden bias to most likely to be affected. Those studies that are most likely to be affected by hidden bias should be taken seriously, but not given the same weight as studies that are less likely to be affected by hidden bias. This study’s structure appears in bold.

1. Clinical Trial

2. Observational Study

   1. Prospective

   2. Retrospective

   3. Cross-sectional

References

Amador-Patarroyo MJ, Arbelaez JG, Mantilla RD, Rodriguez-Rodriguez A, Cárdenas-Roldán J, Pineda-Tamayo R, Guarin MR, Kleine LL, Rojas-Villarraga A, Anaya JM. Sjögren's syndrome at the crossroad of polyautoimmunity. J Autoimmun. 2012 Sep;39(3):199-205. doi: 10.1016/j.jaut.2012.05.008. Epub 2012 Jun 30. PMID: 22749530.