Could I be right? You may well be right.
Studies have shown that memory, and other higher brain functions, can be negatively affected by diabetes. This pertains to both type 1 and type 2 diabetes and to both adults and children. A large part of this effect is related to blood sugar control. Children with repeated episodes of low blood sugar have been shown to have poor long-term memory performance. However, both high and low blood sugar levels are associated with poor memory performance. This affects recall of things previously remembered and memorization of new information. The effect of low blood sugar on memory appears to be the same whether a person is aware of the blood sugar or unaware of it.
When memory problems are associated with high blood sugars, the good news is that they are often reversible with improved control of the diabetes, even in older people. Therefore, if you feel that your memory has deteriorated, a first step would be to ensure that your diabetes is under the best possible control, without unnecessary high or low blood sugars. In addition to controlling blood sugars, it is important to remember that diabetes is a chronic disorder and that we age along with our diabetes. Memory function tends to decline with age, even in people without diabetes. Also, it is possible that some of the medications that you are taking may affect memory, independently of any effect on your blood sugar.
This is particularly true of medications that may cause drowsiness (and therefore inattention to information that you may need to memorize) or low blood pressure. Medications given to treat the pain of neuropathy are the most likely to cause drowsiness. Finally, people with diabetes are at a significantly higher risk of diseases of the blood vessels, including those in the brain, and are at higher risk of brain injury. Such injury may not be noticed as a single severe event, but as a series of smaller unobserved events that ultimately lead to impaired brain functioning, including memory impairment.