Diabetes comes in two forms, Type I and Type II. They are both horrible diseases and in so many ways make a person’s life miserable. By miserable I mean the numerous things required to treat and control it, and the myriad of harmful complications the disease inflicts upon our bodies. Types I and II differ in their pathogenesis, but that doesn’t translate into one disease being worse than the other. Both cause hardening of the arteries, heart attacks, stroke, circulatory problems, retinal damage, kidney failure, and neuropathy (nerve damage).
High blood sugar, or hyperglycemia, is the visual and measurable abnormality doctors use to determine the seriousness of diabetes and how well the disease is being controlled. The goal of treatment is to normalize the Fasting blood sugar to below 120 mg/dL and the HbA1c to 7% or less. Those have been the goals since the American Diabetes Association re-defined the criteria needed to diagnose diabetes.
How “tight” the control should be has led many physicians to question whether lowering the blood sugar and A1c is a good idea. It has been stated that “Tight blood sugar control is necessary to prevent stroke, severe kidney disease, or death.” In other words, many doctors believe lowering the blood sugars reduces a diabetic’s chances of complications. On the opposite side of the spectrum, though, are those who say there is no evidence that lower blood sugars lead to better outcomes; you don’t live longer or have fewer complications just because your blood sugar is normal. There’s more to the disease than that.
A Cochrane Review analysis of glucose control in adults showed that intensive control improved macrovascular outcomes, but it does not increase longevity or improve microvascular changes. That means tight control can lessen large artery and heart disease but not small, or microscopic, vascular disease. Nor will you live longer. In fact, tight A1c control had no long term data to substantiate benefit, except for non-fatal heart attacks.
In elderly patients defined as above 60 years of age, tight blood sugar control is accompanied by a high rate of symptomatic hypoglycemia (low blood sugar—below 70). By symptomatic I mean the blood sugar is low enough to cause staggering gait, dizziness, fatigue, confusion, and even unconsciousness. A study at Veteran’s Hospitals showed standard care patients were hypoglycemic 17.6% of the time while patients tightly controlled ran low blood sugar 24.1% of the time. Plus tight control patients had a six times greater rate of hospitalization for hypoglycemia.
CONCLUSION: Tight A1c control appears to have limited benefit in patients over age 65 and is prone to substantially increase the risk of symptomatic low blood sugar. Tight control may slightly reduce nonfatal heart attacks and delay onset of retinal problems, kidney disease, and neuropathy, but there has not been a “consistent reduction in cardiovascular mortality.”
No doubt diabetics feel better when their blood sugar is 125 rather than 350! And their risk for ketoacidosis, a potentially fatal metabolic complication of diabetes, is all but eliminated. Low blood sugar is the other end of the spectrum. It has serious potential negatives, as well, but can be reversed in seconds. For the elderly, the consequences are serious enough that more lax control of the blood sugar and A1c is recommended. No benefit is derived from lowering the A1c below 7%. And hypoglycemia, a complication of intensive treatment, is to be taken seriously and avoided. Some anti-diabetes drugs contribute to the worsening of vascular disease. Patients on sulfonylureas (glimeperide, glyburide, glipizide) and thiazolidinediones (Actos, Avandia) had worse macrovascular disease and the worst outcomes. This is a case of the treatment being worse than the disease.
Dr. G’s Opinion: Blood sugar and A1c should be lowered as much as possible to give the patient an improved quality of life, but don’t expect him to avoid having the many complications of diabetes, or live longer than the average. He will probably still have diabetic complications despite your best efforts.
References: www.google.com/diabetes-control
Lazris A, Roth A. Intensive Glucose Control in Older Patients with Diabetes. Am Fam Phys 2025 December;112(6):668-670.
