Diabetes patients face 60% higher risk of developing MS

People with type 2 diabetes face higher MS risk, with a review finding they are nearly 60 per cent more likely to develop the condition.

The analysis did not, however, find clear evidence that MS increases the likelihood of developing diabetes.

MS, or multiple sclerosis, happens when the immune system mistakenly attacks the myelin sheath, the fatty layer around nerve fibres that helps nerve signals travel properly. This leads to inflammation and damage in the brain and spinal cord, causing a wide range of symptoms.

Diabetes is a group of long-term conditions marked by persistently high blood sugar levels.

In type 1 diabetes, the immune system attacks insulin-producing cells in the pancreas, reducing the hormone that helps move sugar from the blood into cells for energy.

Type 2 diabetes mainly develops when the body becomes resistant to insulin or the pancreas cannot make enough of it.

Previous research had pointed to a possible link between diabetes and MS, but researchers in China said the nature of that connection, and whether it worked both ways, remained unclear.

Their analysis covered seven studies published between 2010 and 2024, involving more than 3.1 million people.

When data from two studies examining diabetes as a risk factor for MS were pooled, people with diabetes were found to have a 59 per cent higher risk of MS than those without the condition.

Excluding type 1 diabetes, people with type 2 diabetes had a 46 per cent higher risk of developing MS. By contrast, an analysis of five studies found no significant increase in the risk of developing type 2 diabetes among people already diagnosed with MS.

The researchers said several biological mechanisms could help explain why diabetes may increase the risk of MS.

Type 2 diabetes is associated with chronic inflammation and immune system dysregulation, which may affect the brain and spinal cord.

Persistently high blood sugar levels can also trigger metabolic changes that may damage cells responsible for producing and repairing myelin.

By contrast, type 1 diabetes and MS are both autoimmune conditions, suggesting they may share some biological pathways that could partly explain why the diseases sometimes occur in the same individuals.

The team stressed that the findings show an association, but do not prove a direct cause-and-effect relationship.

The researchers wrote: “Although our meta-analysis indicates an association, this does not establish causality.

“Clinicians should maintain heightened vigilance for MS” in people with type 2 diabetes, particularly those presenting with neurological symptoms.

“Conversely, regular blood glucose monitoring is advisable for MS patients to enable early detection and management of potential [diabetes].”

Because the analysis included a relatively small number of studies and different study designs, the researchers said larger, long-term prospective studies will be needed to further clarify the nature of the association between diabetes and MS.