What can happen if my diabetes is not properly treated and controlled?

Uncontrolled diabetes, which generally refers to glucose levels that are higher rather than lower than the target range, can lead  to immediate short-term  and longer- term consequences. The short-term consequences result from  the  very high  blood   glucose itself,  which  is described in Question 4. If severe enough or untreated for long enough, markedly high blood  glucose levels can result in coma and ultimately death, due to  the severe abnormalities of blood chemistry that occur. It is important to note that only a very small minority of patients  with either form of diabetes will die in this way. Therefore,  although immediate decompensation of diabetes is a serious and life-threatening condition, with a high death rate if detected and treated too late, the majority of people with diabetes should  be more concerned about the damaging effects of diabetes that are not well controlled, yet not sufficiently poorly con- trolled to focus their attention. 

The  longer-term  consequences of less than  adequate diabetes control are the result of damage to the small (micro) and larger  (macro) vessels of the circulation. The most common manifestations are diabetic eye dis- ease (retinopathy), which is the leading cause of blind- ness  in  working-age  adults  in  the   United  States; diabetic  kidney  disease (nephropathy),  which  is  the leading cause of severe kidney failure necessitating dial- ysis  or  transplantation  in  working-age adults in  the United States; and nerve damage (neuropathy), which is present in about 1 out of 3 people with diabetes at the time of diagnosis and in over 7 out of 10 by the time diabetes has been present for 10 years. Both retinopa- thy and nephropathy can be entirely without symptoms 

until  they  reach  an  advanced and  irreversible stage, leading to blindness and the need for kidney dialysis or transplant. Diabetic neuropathy can cause very trouble- some symptoms and lead to loss of sensation, mainly in the  feet,  which  places  the  patient  at  high  risk  of trauma, infection, and amputations of the legs and feet.

Disease of the large blood vessels leads to a high rate of heart attack, stroke, heart failure, and amputation of the  (usually  lower)  limbs. About two of every three patients with diabetes will die as a result of large vessel disease. Fortunately,  studies  have  shown  that  good control of diabetes can prevent or delay  the progres- sion of many of these serious problems, but other con- tributing factors, such as blood pressure and cholesterol, must also be given careful attention.

However, we are only achieving target levels of dia- betes control in about half of all people with diabetes in America today.