There is more evidence that diabetes increases the risk of Alzheimer’s disease.

Two new studies definitively tie Type 2 diabetes, the kind usually related to obesity, with increased risk of Alzheimer’s. One of the studies reported by the Alzheimer’s Association at a six-day conference in Madrid, Spain, found that even people who had borderline diabetes were 70% more likely than those with normal blood sugar to develop Alzheimer’s.

Another study determined that diabetics with higher blood sugar levels are at a greater the risk of dementia. Higher levels of blood sugar mean the diabetes is severe or is being poorly treated, or both, said researcher Rachel A. Whitmer of the Division of Research at Kaiser Permanente in Oakland, CA. Results imply there should be tight control of blood sugar in elderly patients, even though some doctors tend to relax the rules for them, Whitmer said.