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What is type 1 diabetes?

Type 1 diabetes may also be known by a variety of other names, including the following:

• Insulin-dependent diabetes mellitus (IDDM)

• Juvenile diabetes

There are two forms of type 1 diabetes:

• Idiopathic type 1 diabetes. This refers to rare forms of the disease with no known
  cause.

• Immune-mediated diabetes. An autoimmune disorder in which the body’s immune system
  destroys, or attempts to destroy, the cells in the pancreas that produce insulin.

Immune-mediated diabetes is the most common form of type 1 diabetes, and the one generally
referred to as type 1 diabetes. The information on this page refers to this form of
type 1 diabetes.

Type 1 diabetes accounts for about 5 percent of all diagnosed cases of diabetes in
the U.S. Type 1 diabetes usually develops in children or young adults, but can start
at any age.

What causes type 1 diabetes?

The cause of type 1 diabetes is unknown, but it is believed to result from the immune
system being triggered. The body’s immune system attacks and destroys the insulin
producing cells in the pancreas. Insulin allows glucose to enter the cells of the
body to provide energy.

When glucose cannot enter the cells, it builds up in the blood, depriving the cells
of nutrition. People with type 1 diabetes must take daily insulin injections and regularly
monitor their blood sugar levels.

What are the symptoms of type 1 diabetes?

Type 1 diabetes often appears suddenly. The following are the most common symptoms
of type 1 diabetes. However, each individual may experience symptoms differently.
Symptoms may include:

• Unusual thirst

• Frequent urination

• Unexplained weight loss despite extreme hunger

• Blurred vision

• Nausea and vomiting

• Extreme weakness and fatigue

• Irritability and mood changes

In children, symptoms may be similar to those of having the flu. Some very young children
may start bedwetting again.

The symptoms of type 1 diabetes may resemble other conditions or medical problems.
Always consult your doctor for a diagnosis.

What complications may be associated with type 1 diabetes?

Type 1 diabetes can cause many different problems. However, the three key complications
of diabetes include the following:

1. Kidney failure

2. Blindness

3. Ketoacidosis (high blood sugar and a build up of acids in the blood due to untreated
   or undertreated diabetes)

4. Heart attack

5. Stroke

6. Foot ulcers

7. Amputations

What is the treatment for type 1 diabetes?

Treatment of type 1 diabetes requires insulin. Your specific type of insulin plan
will be determined by your doctor based on:

• Your age, overall health, and medical history

• Extent of the disease

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

• Cost of therapy

People with type 1 diabetes must have daily injections of insulin to keep their blood
sugar level within normal ranges. Other parts of the treatment protocol may include:

• Appropriate diet (to manage blood sugar levels)

• Exercise (to lower and help the body use blood sugar)

• Careful self-monitoring of blood sugar levels several times a day and keeping a log,
  as directed by your doctor

• Careful self-monitoring of ketone levels in the urine several times a day, as directed
  by your doctor

• Regular monitoring of the hemoglobin A1c levels

The hemoglobin A1c test (also called HbA1c test) shows the average amount of sugar
in the blood over the last three months. The result will indicate if the blood sugar
level is under control. The frequency of HbA1c testing will be determined by your
doctor. The American Diabetes Association (ADA) recommends that testing occur at least
twice a year if the blood sugar level is in the target range and stable, and more
frequently if the blood sugar level is unstable. Most people with type 1 diabetes
require 3 monthly HbA1c tests.

Advances in diabetes research have led to improved methods of managing diabetes and
treating its complications. However, scientists continue to explore the causes of
diabetes and ways to prevent and treat the disorder. Other methods of administering
insulin through inhalers and pills are currently being studied. Scientists are investigating
gene involvement in type 1 and type 2 diabetes, and some genetic markers for type
1 diabetes have been identified. Pancreas and islet cell transplants are also being
performed.

What is type 2 diabetes?

Type 2 diabetes is a metabolic disorder resulting from the body’s inability to make
enough insulin for the degree of insulin resistance (body’s inability to properly
use insulin). It used to be called non-insulin-dependent diabetes mellitus, or maturity-onset
diabetes mellitus (NIDDM).

Without adequate production or utilization of insulin, the body cannot move blood
sugar into the cells. It is a chronic disease that has no known cure. It is the most
common type of diabetes.

What is prediabetes?

Type 2 diabetes is commonly preceded by prediabetes. In prediabetes, blood glucose
levels are higher than normal but not high enough to be defined as diabetes. However,
many people with prediabetes develop type 2 diabetes within 10 years, states the National
Institute of Diabetes and Digestive and Kidney Diseases. Prediabetes also increases
the risk of heart disease and stroke. With modest weight loss and moderate physical
activity, people with prediabetes can delay or prevent type 2 diabetes.

Prediabetes affects 79 million people in the US, according to the ADA.

What causes type 2 diabetes?

The exact cause of type 2 diabetes is unknown. However, there does appear to be a
genetic factor which causes it to run in families. Although a person can inherit a
tendency to develop type 2 diabetes, it usually takes another factor, such as obesity
or physical inactivity, to bring on the disease.

Can type 2 diabetes be prevented or delayed?

Type 2 diabetes may be prevented or delayed by following a program to eliminate or
reduce risk factors–particularly losing weight (as little as 5 to 10 percent) and
increasing exercise (30 minutes a day, 5 days a week). Information gathered by the
Diabetes Prevention Program, sponsored by the National Institutes of Health and the
ADA, continues to study this possibility.

What are the symptoms of type 2 diabetes?

Most people with type 2 diabetes have no symptoms. It is usually diagnosed on blood
tests during routine clinical evaluations. However, each individual may experience
symptoms differently. Symptoms may include:

• Frequent infections that do not heal easily

• Unusual thirst

• Frequent urination

• Weight loss despite extreme hunger

• Blurred vision

• Nausea and vomiting

• Extreme weakness and fatigue

• Irritability and mood changes

• Dry, itchy skin

• Tingling or loss of feeling in the hands or feet

Some people who have type 2 diabetes exhibit no symptoms. Symptoms may be mild and
almost unnoticeable, or easy to confuse with signs of aging. Half of all Americans
who have diabetes do not know it.

The symptoms of type 2 diabetes may resemble other conditions or medical problems.
Always consult your doctor for a diagnosis.

What are the risk factors for type 2 diabetes?

Risk factors for type 2 diabetes include:

• Age. People over the age of 45 are at higher risk for diabetes.

• Family history of diabetes

• Being overweight

• Not exercising regularly

• Race and ethnicity. Being a member of certain racial and ethnic groups, such as African-Americans,
  Hispanic Americans, and American Indians increases the risk for type 2 diabetes.

• Pregnancy

• History of gestational diabetes, or giving birth to a baby who weighed more than 9
  pounds

• A low level HDL (“good”) cholesterol

• A high triglyceride level

What is the treatment for type 2 diabetes?

Specific treatment for type 2 diabetes will be determined by your doctor based on:

• Your age, overall health, and medical history

• Extent of the disease

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

• Cost of therapy

The goal of treatment is to keep blood sugar levels as close to normal as safely possible.
Emphasis is on control of blood sugar (glucose) by monitoring the levels, regular
physical activity, meal planning, and routine health care. Treatment of diabetes is
an ongoing process of management and education that includes not only the person with
diabetes, but also health care professionals and family members.

Often, type 2 diabetes can be controlled through losing weight, improved nutrition,
and exercise alone. However, over time, these measures are not enough and either oral
or injected medications and/or insulin must be used. Treatment often includes:

• Proper diet

• Weight control

• An appropriate exercise program

• Regular foot inspections

• Oral medications, other medications, and/or insulin replacement therapy, as directed
  by your doctor. There are various types of medications that may be used to treat type
  2 diabetes when lifestyle changes, such as diet, exercise, and weight loss are no
  longer effective. Oral medications of several different types are available, with
  each type working in a different manner to lower blood sugar and each one with different
  side effects. One medication may be combined with another one to improve blood sugar
  control. When oral medications are no longer effective, insulin may be required.
  New medications for treating diabetes are in development.

• Regular monitoring of the hemoglobin A1c levels. The hemoglobin A1c test (also called
  HbA1c test) shows the average amount of sugar in the blood over the last three months.
  The result will indicate if the blood sugar level is under control. The frequency
  of HbA1c testing will be determined by your doctor. It is recommended that testing
  occur at least twice a year if the blood sugar level is in the target range and stable,
  and more frequently if the blood sugar level is unstable.

Untreated or inappropriately treated diabetes can cause problems with the kidneys,
legs, feet, eyes, heart, nerves, and blood flow, which could lead to kidney failure,
gangrene, amputation, blindness, heart attack or stroke. For these reasons, it is
important to follow a strict treatment plan.

What is gestational diabetes?

Gestational diabetes is a condition in which the glucose level is elevated and other
diabetic symptoms appear during pregnancy in a woman who has not previously been diagnosed
with diabetes. Diabetes disappears following delivery. All diabetic symptoms disappear
following delivery.

Unlike type 1 diabetes, gestational diabetes is not caused by an absolute lack of
insulin, but rather by the effects of hormones released during pregnancy on the insulin
that is produced, a condition referred to as insulin resistance.

According to the CDC, approximately 2 to 10 percent of all pregnant women in the U.S.
are diagnosed with gestational diabetes.

What causes gestational diabetes mellitus (GDM)?

Although the cause of GDM is not known, there are some theories as to why the condition
occurs.

The placenta supplies a growing fetus with nutrients and water, and also produces
a variety of hormones to maintain the pregnancy. Some of these hormones (estrogen,
cortisol, and human placental lactogen) can interfere with the effects of insulin.
This is called contra-insulin effect, which usually begins about 20 to 24 weeks into
the pregnancy.

As the placenta grows, more of these hormones are produced, and insulin resistance
becomes greater. Normally, the pancreas is able to make additional insulin to overcome
insulin resistance, but when the production of insulin is not enough to overcome the
effect of the placental hormones, gestational diabetes results.

What are the risks factors associated with GDM?

Although any woman can develop GDM during pregnancy, some of the factors that may
increase the risk include the following:

• Overweight or obesity

• Family history of diabetes

• Prior history of gestational diabetes during previous pregnancies

• Having given birth previously to a very large infant greater than nine pounds

• Age. Women who are age 25 or older are at a greater risk for developing gestational
  diabetes than younger women.

• Race. Women who are African-American, American Indian, Asian-American, Hispanic, or
  Pacific Islander have a higher risk.

• History of prediabetes

Although increased glucose in the urine is often included in the list of risk factors,
it is not believed to be a reliable indicator for GDM.

How is GDM diagnosed?

New Standards of Medical Care in Diabetes-2013 from the ADA recommend screening for undiagnosed type 2 diabetes at the first prenatal
visit in women with diabetes risk factors. In pregnant women not known to have diabetes,
GDM testing should be performed at 24 to 28 weeks of gestation.

In addition, women with diagnosed GDM should be screened for persistent diabetes six
to 12 weeks postpartum. Women with a history of GDM are now recommended to have lifelong
screening for the development of diabetes or prediabetes at least every three years.

What is the treatment for gestational diabetes?

Specific treatment for gestational diabetes will be determined by your doctor based
on:

• Your age, overall health, and medical history

• Extent of the disease

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

Treatment for gestational diabetes focuses on keeping blood glucose levels in the
normal range. Treatment may include:

• Special diet

• Exercise

• Daily blood glucose monitoring

• Insulin injections

• Oral antidiabetic medication

What are possible complications for the baby?

Unlike type 1 diabetes, gestational diabetes generally does not cause birth defects.
Birth defects usually originate sometime during the first trimester (before the 13th
week) of pregnancy. The insulin resistance from the counter-insulin hormones produced
by the placenta does not usually occur until approximately the 24th week. Women with
gestational diabetes generally have normal blood sugar levels during the critical
first trimester.

The complications of gestational diabetes are usually preventable or manageable. The
key to prevention is careful control of blood sugar levels just as soon as the diagnosis
of gestational diabetes is made.

Infants of mothers with gestational diabetes are vulnerable to several problems at
birth, such as low serum calcium and low serum magnesium levels, but, in general,
there are two major problems of gestational diabetes: macrosomia and hypoglycemia:

• Macrosomia. Macrosomia refers to a baby that is considerably larger than normal. All
  of the nutrients the fetus receives come directly from the mother’s blood. If the
  maternal blood has too much glucose, the pancreas of the fetus senses the high glucose
  levels and produces more insulin in an attempt to use this glucose. The fetus converts
  the extra glucose to fat. Even when the mother has gestational diabetes, the fetus
  is able to produce all the insulin it needs. The combination of high blood glucose
  levels from the mother and high insulin levels in the fetus results in large deposits
  of fat that causes the fetus to grow excessively large. This may lead to difficulty
  in delivery, as the baby may be bigger than the birth canal.

• Hypoglycemia. Hypoglycemia refers to low blood sugar in the baby immediately after
  delivery. This problem occurs if the mother’s blood sugar levels have been consistently
  high, causing the fetus to have a high level of insulin in its circulation. After
  delivery, the baby continues to have a high insulin level, but it no longer has the
  high level of sugar from its mother, resulting in the newborn’s blood sugar level
  becoming very low. The baby’s blood sugar level is checked after birth, and if the
  level is too low, it may be necessary to give the baby glucose intravenously.