Is it true that diabetes result in confusion, loss of memory?

You are correct!: Uncontrolled diabetes may result in diabetic ketoacidosis/coma--excessive sugar is toxic to brain cells..Actually all cells. We know that diabetics suffer more strokes and at much higher risk of developing dementia. Risk of heart attacks, blindness, kidney failures, neuropathic pain, limb amputations are some of other concerning complications. So treat it well. Consult doc regularly. Good luck.