Not only are people with type 2 diabetes more prone to depression, but people with depression are more prone to getting diabetes, a new study in the June 18 issue of the Journal of the American Medical Association claims.

Researchers have long known that type 2 diabetes and depression often go hand-in-hand, according to the study, so researchers with Johns Hopkins Medical Institutions in Baltimore set out to determine which comes first.

Dr. Sherita Hill Golden and her colleagues looked at data from an ethnically diverse group of 6,814 men and women between 45 and 84. Study participants identified themselves as white, black, Hispanic or Chinese.

Participants made three visits to clinics over three years.

Results showed that those with the strongest symptoms of depression were 42 percent more likely on average to develop diabetes by the end of the study than those without depressive symptoms.

Even when the researchers accounted for factors such as being overweight, lack of exercise and smoking, the risk of developing diabetes still was 34 percent higher for patients who were depressed.

The researchers also found that patients treated for diabetes, about 9 percent of the group, were about 54 percent more likely to develop elevated symptoms of depression than those without diabetes.

"Having both diabetes and depression can make it difficult for patients to get the good clinical outcomes that we like to see for each of these conditions," Golden said in a news release.

"It's important that doctors be attuned to look for both conditions in patients at risk for either diabetes or depression," Golden added. "We may want to develop interventions for both treatments, instead of just one or the other."

Click here to see the study.