Addressing inflammation in diabetics may treat depression, but methods may vary: Study

An analysis has revealed that addressing inflammation in diabetes can help determine success in treating depression in a group of patients. However, there are differences in outcomes between type 1 and type 2 diabetes, researchers said.

While type 2 diabetes is a metabolic condition marked by an inability to manage blood sugar, type 1 diabetes is an autoimmune disorder in which the body’s immune system mistakenly attacks and damages insulin-producing cells in the pancreas.

“People with type 2 diabetes and high inflammation levels possibly respond particularly well to a change in depressive cognitions through cognitive behavioural therapy. People with type 1 diabetes and high inflammation levels, on the other hand, could benefit more from anti-inflammatory drug therapies,” said author Norbert Hermanns from the Research Institute of the Diabetes Academy Mergentheim (FIDAM), Germany.

Findings published in the journal Diabetologia could help develop customised treatment plans for diabetics, who might be doubly vulnerable to depression compared to the general population, the team said.

Diabetes is often accompanied by anxiety and negative feelings of sickness, which constitute depressive symptoms and can impair progress in treatment.

The researchers said that while early diagnosis and effective treatment of depression in diabetics is important, not all respond equally — whether with medication or cognitive behavioural therapy (a form of psychotherapy).

The team looked at 521 people with type 1 or type 2 diabetes and analysed how their depressive symptoms responded to behavioural therapy over a year.

Measuring 76 inflammatory markers in the blood, the research team examined whether there was a link between inflammation levels and the severity of depression.

Among people with type 2 diabetes and higher levels of inflammation, cognitive behavioural therapy was found to improve depressive symptoms, including joylessness.

However, among patients with type 1 diabetes and high inflammation, behavioural therapy was found to produce smaller improvements, especially in fatigue, sleep disorders, or loss of appetite.

It is possible that distinct immune processes — autoimmune processes in type 1 diabetes and metabolic inflammation in type 2 diabetes — could be responsible for the differences in outcomes, the researchers said, adding that future research could help better understand this.

“In people with type 2 diabetes, higher levels of 26 biomarkers were associated with greater reductions in depressive symptoms, whereas in people with type 1 diabetes, higher levels of 13 biomarkers were linked with lower reductions in depressive symptoms,” the authors wrote.

“There were also diabetes type-specific differences in the associations with symptom clusters of depression. This suggests that different inflammation-related pathways may be relevant for the response to depression treatment in people with type 1 diabetes or type 2 diabetes,” they wrote.