A study led by Dr Wayne Katon from the University of Washington has been looking into the unholy trinity of diabetes, depression and dementia. Diabetes and major depression have both been found to be risk factors for dementia. Diabetes increases the risk of dementia by between 40 and 100% while a history of depression more than doubles the subsequent risk of Alzheimer's disease. Depression is also more common in people with diabetes and the study looked into the effects of depression and diabetes together on the risk of developing dementia. The study looked at 3,837 people with diabetes of whom 455 had major depression. 7.9% of people with diabetes and depression developed dementia over the course of the five-year study compared to only 4.8% of those with diabetes alone. The researchers calculated that major depression and diabetes had a 2.7x greater risk of dementia than diabetes alone.
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