Complications 

Kidney Disease

• Diabetes is the leading cause of kidney failure, accounting for 44% of all new cases of kidney failure in 2008.

  • In 2008, 48,374 people with diabetes began treatment for end-stage kidney disease.
    
  • In 2008, a total of 202,290 people with end-stage kidney disease due to diabetes were living on chronic dialysis or with a kidney transplant.

• In 2005–2008, of adults aged 20 years or older with self-reported diabetes, 67% had blood pressure greater than or equal to 140/90 millimeters of mercury (mmHg) or used prescription medications for hypertension.
  
  Heart Disease and Strokes  

  • In 2004, heart disease was noted on 68% of diabetes-related death certificates among people aged 65 years or older.
    
  • In 2004, stroke was noted on 16% of diabetes-related death certificates among people aged 65 years or older.
    
  • Adults with diabetes have heart disease death rates about 2 to 4 times higher than adults without diabetes.
    
  • The risk for stroke is 2 to 4 times higher among people with diabetes.

  
  

• In 2005–2008, 4.2 million (28.5%) people with diabetes aged 40 years or older had diabetic retinopathy, and of these, 655,000 (4.4% of those with diabetes) had advanced diabetic retinopathy that could lead to severe vision loss.  

Nerve Disease

Amputations

• More than 60% of nontraumatic lower-limb amputations occur in people with diabetes.
  
• In 2006, about 65,700 nontraumatic lower-limb amputations were performed in people with diabetes. 

Dental disease

• Periodontal (gum) disease is more common in people with diabetes. Among young adults, those with diabetes have about twice the risk of those without diabetes.
  
• Adults aged 45 years or older with poorly controlled diabetes (A1c > 9%) were 2.9 times more likely to have severe periodontitis than those without diabetes. The likelihood was even greater (4.6 times) among smokers with poorly controlled diabetes.
  
• About one-third of people with diabetes have severe periodontal disease consisting of loss of attachment (5 millimeters or more) of the gums to the teeth.

Complications of pregnancy

• Poorly controlled diabetes before conception and during the first trimester of pregnancy among women with type 1 diabetes can cause major birth defects in 5% to 10% of pregnancies and spontaneous abortions in 15% to 20% of pregnancies. On the other hand, for a woman with pre-existing diabetes, optimizing blood glucose levels before and during early pregnancy can reduce the risk of birth defects in their infants. 
  
• Poorly controlled diabetes during the second and third trimesters of pregnancy can result in excessively large babies, posing a risk to both mother and child.

Other complications

• Uncontrolled diabetes often leads to biochemical imbalances that can cause acute life-threatening events, such as diabetic ketoacidosis and hyperosmolar (nonketotic) coma.
  
• People with diabetes are more susceptible to many other illnesses. Once they acquire these illnesses, they often have worse prognoses. For example, they are more likely to die with pneumonia or influenza than people who do not have diabetes.
  
• People with diabetes aged 60 years or older are 2–3 times more likely to report an inability to walk one-quarter of a mile, climb stairs, or do housework compared with people without diabetes in the same age group.
  
• People with diabetes are twice as likely to have depression, which can complicate diabetes management, than people without diabetes. In addition, depression is associated with a 60% increased risk of developing type 2 diabetes.
  
• Diabetes can also lead to hearing impairment.
  
• Type 2 diabetes may increase the risk of Alzheimer's disease and vascular dementia. The poorer your blood sugar control, the greater the risk appears to be. So what connects the two conditions? One theory is that cardiovascular problems caused by diabetes could contribute to dementia by blocking blood flow to the brain or causing strokes. Other possibilities are that too much insulin in the blood leads to brain-damaging inflammation, or lack of insulin in the brain deprives brain cells of glucose.