linkage between t1d and multiple sclerosis

Disease Cousins: Linkage Between Type 1 Diabetes and Multiple Sclerosis.

By Jaylyn Porras and Mariana Turner

Like T1D, multiple sclerosis is an autoimmune disease in which the immune system mistakenly attacks the myelin sheath, the insulating cover of the nerve cells in your brain and spinal cord. Although it is  a rare disease,  scientists are finding that having Type 1 diabetes is a risk factor for having MS. T1D and MS contribute considerably to the burden of autoimmune diseases in young adults. The two conditions have been linked with distinct human leukocyte antigen (HLA) haplotypes but share a number of similarities in clinical, epidemiological and immunological features, leading to suggestions of possible common mechanisms of development. 

T1D and MS

Type 1 diabetes mellitus (T1D) and multiple sclerosis (MS) are common autoimmune diseases in young adults. While many believe that the diseases are mutually exclusive, they share individual and familial co-occurrence of the 2 diseases. In order to provide further information about these “disease cousins” the risk for MS in patients with T1D and the risk in first-degree relatives of patients with MS were estimated. They found that: 

  • “Patients with T1D and first-degree relatives of patients with MS were followed up for occurrence of MS and T1D”. Patients with T1D were more at risks and patients with MS were at 63% increased risk.
  • Adult women with type 1 diabetes are at an enormously increased risk of multiple sclerosis, and that the answer to questions about the clustering of these disorders is that they are “together at last.” 

Honeymoon Phase

During the “honeymoon” phase of diagnosed patients with Type 1 diabetes, disease cousins of T1D can use that opportunity to develop. In this somewhat remission period results showed that patients in younger age with onset diabetes are predicted to develop Celiac Disease. Patients with a longer honeymoon phase were more at risk of developing an associated autoimmune disease.  

The takeaway? Further epidemiologic studies are needed to confirm our findings. Genetic studies are also required to evaluate the DRB1*0301, DRB1*0405, and DRB1*15 extended haplotypes for common alleles at other loci that may contribute to the familial clustering of multiple sclerosis and type 1 diabetes. Evidence on whether the co-occurrence of the T1D and MS will affect the disease course and severity of MS is little to none. Therefore, more studies need to be conducted to discover whether the neuropathology associated with T1D might influence the disease course and contribute to the severity of MS.


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  • Ozen, Gulsum, et al. “The Association of Autoimmune Diseases with Type 1 Diabetes Mellitus in Children Depends Also by the Length of Partial Clinical Remission Phase (Honeymoon).” International Journal of Endocrinology, Hindawi, 4 Jan. 2020,
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