AGEs are chemically very reactive, and they combine with other molecules to form bonds called cross-links. These cross-links change the nature of the body’s cells, tissues, and blood vessels, making them stiff and dysfunctional. While these changes occur in all people as they age, the process is greatly accelerated in people with diabetes. AGEs are thought to contribute to diabetes complications, including cardiovascular disease, diabetic eye disease, diabetic nerve disease, and diabetic kidney disease.
Diabetes complications can also speed up the aging process. Eye diseases related to diabetes, including retinopathy, macular edema, and cataracts, can worsen already fading eyesight. Diabetic nerve disease can complicate the arthritis that comes with age, sometimes allowing greater joint erosion in the foot (a condition known as Charcot joint). Diabetic kidney disease can speed the decline in kidney function often seen with age. Cardiovascular disease can age virtually any tissue in the body by diminishing its blood supply.
How aging may affect diabetes control
Aging can make diabetes more difficult to control. One reason for this is that insulin resistance increases and glucose tolerance decreases with age, but there are other, indirect reasons as well.
As people’s attention declines with age, they may be less able to focus on the tasks associated with diabetes management, such as carbohydrate counting, meal planning, blood glucose monitoring, and determining correct insulin doses. Furthermore, loss of visual acuity may make it more difficult to accurately monitor blood glucose levels or draw up insulin doses.
One major problem in elderly individuals with diabetes is hypoglycemia, or low blood glucose. Elderly people with diabetes are especially prone to hypoglycemia for a number of reasons, including the following:
- Many elderly people take multiple drugs, some of which may directly cause hypoglycemia, and some of which may interact with diabetes drugs to cause hypoglycemia.
- Elderly people may have impaired glucose counterregulation, a condition in which the body is less likely to release certain hormones that normally protect against low blood glucose levels by raising blood glucose levels when they fall dangerously low. People with impaired glucose counterregulation are also less likely to experience the usual symptoms that herald the onset of hypoglycemic episodes, such as sweating, trembling, dizziness, and headache, which prevents them from taking the necessary steps to address it. And even if they are aware of the hypoglycemia, the cognitive symptoms of severe hypoglycemia (such as confusion) may prevent them from responding appropriately.
- Elderly people may be at greater risk for an age-related decline in liver and kidney function, which may slow down the metabolism of certain oral diabetes drugs. This can leave the drugs in their bloodstream longer than normal, setting the stage for hypoglycemia.
- Elderly people may be more likely to have poor appetites and miss meals—especially if they have delayed stomach emptying from diabetic autonomic neuropathy—and this may predispose them to developing hypoglycemia.