Several severe disabling conditions among older individuals may arise from diabetes mellitus. For example, one of the four leading causes of blindness in those over the age of 40 is diabetic retinopathy.61 In addition, other vascular complications of diabetes (e.g., vascular disease in the lower extremities) may inhibit walking. Diabetic vascular disease in the legs, especially when combined with smoking, is a major cause of amputation among the elderly.64,104 Finally, the elderly with diabetes, especially uncontrolled diabetes, are also more likely than the nondiabetic to develop cognitive impairments, a probability that applies to those with Type II diabetes.85 Yet diabetes mellitus is another common cardiovascular disease risk factor that can be controlled in part by dietary interventions. Diabetic control in adult onset diabetes (Type II, or non-insulin-dependent diabetes mellitus) can often be achieved without the use of insulin or oral hypoglycemic agents using dietary manipulation and adjustments in exercise. Patients who suffer from insulin-dependent diabetes (Type I) generally require extensive dietary counseling.
Weight loss alone can often bring satisfactory control of non-insulin-dependent diabetes. In a recent study of elderly individuals suffering from Type II diabetes, a combination of dietary counseling and peer support resulted in weight loss and improved diabetic control as measured by glycosylated haemoglobin.118 Four months later, however, most of the elderly participants had returned to their original weight, pointing to the need for continued dietary counseling and assistance. In addition, even after weight loss, some elderly non-insulin-dependent diabetics continue to require drugs to achieve satisfactory glycemic control or to achieve better values on other risk factors that may also need modification (e.g., serum cholesterol). At present, estimates of the effectiveness of nutritional interventions are optimistic, but there are too few data to make definitive judgements.54
Most studies of interventions for diabetes involve young and middle-aged populations rather than the elderly. Nevertheless, some generalization is possible. The effects of diabetes education programs on subsequent hospitalization for diabetes, especially those admissions related to a lack of diabetes self-management skills, have been the subject of several studies; it appears that hospital admissions do decrease following such programs, although the programs usually involve some form of residence in a hospital for training and therefore are rather costly.30 Other programs that have a similar goal—to help patients manage their diets and medications more completely—but that involve ambulatory care also appear to be effective and are less expensive than programs with a hospital training component.20,105,116