Depression and Type 2 diabetes have been linked with an increased risk for dementia — a risk that rises dramatically in individuals with both conditions.

The findings, published online in the journal JAMA Psychiatry, could help doctors identify patients who might be at risk for developing Alzheimer’s disease and other forms of dementia even before symptoms appear, Medical Xpress reports.

That could, in turn, help speed treatments that can slow progression of the brain-wasting disease.

The study — led by the late Wayne Katon, professor of psychiatry and behavioral sciences at the University of Washington — more than 2.4 million Danish citizens, who were 50 and older from 2007 through 2013, and compared their rates of dementia, depression, diabetes or all three.

Overall, the researchers found nearly one in five had a diagnosis of depression, about 9.1 percent had Type 2 diabetes, and nearly 4 percent had both. The results also indicated 2.4 percent of the participants developed dementia over the course of the study.

Of the dementia suffers, 26.4 percent had depression, 10.8 percent had diabetes, and 7 percent had both conditions.

The results indicate diabetes is associated with a 20 percent greater risk for dementia, while depression is linked with an 83 percent greater risk. But having both depression and type 2 diabetes was associated with a whopping 117 percent greater risk for dementia.

"In light of the increasing societal burden of chronic diseases, further research is needed to elucidate the pathophysiologic mechanisms linking depression, [diabetes] and adverse outcomes such as dementia and to develop interventions aimed at preventing these dreaded complications," the study concludes.