All diabetics do not develop complications. If the blood sugar levels are carefully controlled, in both types 1 and 2 diabetes, complications may never develop. But in order to achieve this, lifestyle changes that are consistently maintained are also necessary.
Diabetic complications involve several different organs or parts of the body. The eyes, the kidneys, the circulatory system, the brain, the heart and the feet/lower legs could all be potentially affected.
Most people who have developed diabetic complications have been diabetic for some time. It is unlikely that it is only diagnosed when problems occur with the organs mentioned above. Most diabetics are diagnosed in routine checkups, or when they show some of the other symptoms of diabetes, such as increased thirst, or frequent urination, or inexplicable weight loss or gain. In type 1 diabetics, often children, the diagnosis is frequently only made after a diabetic coma sets in.
But people who have been diabetic for some time should be on the lookout for any signs of heart trouble, such as chest pain, blurred vision or a tingling sensation in the lower legs and feet. Lower back pain often also signifies kidney problems. Numbness anywhere in the body should also be a call to take action and get to a doctor. - (Health24, February 2010)