HAMBURG (Deutsche Presse-Agentur) -- Depression can heighten the risk of developing type 2 diabetes as the mental illness also increases the likelihood of obesity and failing to take enough exercise, a study carried out by the German Diabetes Association (DDG) has shown.

Bouts of depression can also lead to higher levels of the stress hormone cortisol in the blood.

Cortisol, also known as hydrocortisone, counteracts insulin and contributes to type 2 diabetes, which is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency.

It is recommended that those suffering from depression undergo tests for the disease as they are 11 times more likely to suffer vascular complications than people battling diabetes alone.

The risk of damage to arteries, which could lead to a heart attack, is between two and five times as high.

According to the DDG, not only are people with depression at increased risk of developing type 2 diabetes, those with diabetes are also at increased risk of developing depression.

The consequences can be serious as treatment for diabetes requires the active involvement of the patient.

"Depression is a major barrier in such instances," explains Bernhard Kulzer, chairman of the DDG's psychology council.

Complications that can result from improperly managed type 2 diabetes include renal failure, blindness and arterial disease, including coronary artery disease.

The DDG recommends that diabetics suffering from depression undergo psychological treatment.

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