Senior Medical Advisor · Last reviewed January 2025
Diabetes complications — both microvascular (affecting small blood vessels) and macrovascular (affecting large blood vessels) — are the primary driver of morbidity and mortality in individuals with diabetes. The landmark DCCT trial in Type 1 diabetes and the UKPDS in Type 2 diabetes established that intensive glycemic control substantially reduces the risk of microvascular complications. Subsequent research has confirmed the importance of addressing cardiovascular risk factors — blood pressure, lipids, and smoking — in reducing macrovascular complications.
Microvascular Complications
Diabetic neuropathy — affecting approximately 50% of individuals with long-standing diabetes — involves damage to peripheral nerves, typically presenting as numbness, tingling, or burning pain in the feet and lower extremities. Autonomic neuropathy affects the cardiovascular, gastrointestinal, and genitourinary systems. Tight glycemic control remains the primary prevention strategy.
Diabetic retinopathy — the leading cause of new blindness in working-age adults in the United States — results from damage to retinal microvasculature. Annual dilated eye exams are essential for early detection, as early-stage retinopathy is treatable with laser photocoagulation and anti-VEGF injections before significant vision loss occurs.
Diabetic nephropathy (diabetic kidney disease) is the leading cause of end-stage renal disease in the United States. Regular screening with urine albumin-to-creatinine ratio and eGFR, blood pressure control (particularly with ACE inhibitors or ARBs), and SGLT-2 inhibitors (which have demonstrated renal protective effects beyond glycemic control) are the primary management approaches.
Macrovascular Complications
Individuals with diabetes have two to four times the cardiovascular disease risk of those without diabetes. Cardiovascular risk reduction — through statin therapy, blood pressure control, smoking cessation, and antiplatelet therapy in those with established CVD — is as important as glycemic control for reducing mortality. GLP-1 receptor agonists and SGLT-2 inhibitors have demonstrated cardiovascular risk reduction in individuals with established cardiovascular disease beyond their glucose-lowering effects.
Foot Health
Diabetic foot complications — ulcers, infections, and amputations — result from the combination of neuropathy (reducing pain sensation) and peripheral arterial disease. Annual comprehensive foot exams, daily self-inspection, appropriate footwear, and prompt treatment of foot injuries are critical preventive measures. Lower extremity amputations are 10 times more common in individuals with diabetes than in the general population, yet most are preventable with appropriate preventive care.
Related: Diabetes Overview · Type 2 Diabetes Management · Heart Disease