Type 1
Definition: Previously called insulin-dependent diabetes mellitus (IDDM) or juvenile-onset diabetes, type 1 is an autoimmune disease in which the body makes little or no insulin.
Risk factors: Type 1 develops most often in children and young adults before age 30, although it can appear at any age. There is no known cause and, thus, no way to prevent it. It is not caused by consuming too much sugar.
Symptoms: Usually develop over a short period, although cell destruction can begin years earlier. Symptoms include increased thirst and urination, constant hunger, unexplained weight loss, blurred vision, extreme fatigue, tingling or numbness in hands or feet, very dry skin, sores that are slow to heal and more infections than usual. Those affected do not necessarily show symptoms. Risk factors are less well defined for type 1 than for type 2, but autoimmune, genetic and environmental factors are involved.
Treatments: A person who has type 1 diabetes must take insulin daily to live. Lifestyle changes such as healthy eating and increased physical activity are basic therapies. Blood glucose levels must be closely monitored through frequent blood glucose testing.
Complications: Early heart disease, amputation, stroke, kidney failure, nerve damage, blindness.
Type 2
Definition: Previously called non-insulin-dependent diabetes mellitus (NIDDM) or adult-onset diabetes, type 2 is the most commonly diagnosed type of diabetes. With type 2 diabetes, the body can't use the insulin it makes.
Risk factors: Associated with those age 40 or older, obesity, family history of diabetes, high blood pressure, abnormal cholesterol levels, schizophrenia, polycystic ovary syndrome, acanthosis nigricans (darkened patches of skin), previous history of gestational diabetes, history of giving birth to a baby more than 9 pounds, physical inactivity and ethnicity (Aboriginal, Hispanic, Asian, South Asian, or African descent); type 2 is increasingly being diagnosed in children and adolescents.
Symptoms: Develop more slowly and may include fatigue or nausea, frequent urination, unusual thirst, weight loss, blurred vision, frequent infections and slow healing of wounds or sores; or there can be no symptoms.
Treatments: Healthy eating, physical activity and blood glucose testing are basic therapies. Many require oral medication, insulin or both to control blood glucose levels.
Complications: High blood glucose levels over a long period can cause blindness, heart disease, kidney problems, amputations, nerve damage and erectile dysfunction.
Gestational
Definition: Glucose intolerance, but with first onset during pregnancy.
Risk factors: It only affects women during pregnancy and usually disappears after pregnancy. Risk factors include a history of gestational diabetes, age over 35, obesity, a history of polycystic ovary syndrome, hirsutism (excessive hair growth in women), acanthosis nigricans and being a member of a population considered to be at high risk for diabetes.
Symptoms: The Canadian Diabetes Association's 2003 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada recommend that all women be screened between 24 and 28 weeks gestation using a glucose tolerance test. For those with multiple risk factors, this testing should be done during the first trimester, then again during the second and third trimesters, even if the first test is negative.
Treatments: Similar to managing type 2 diabetes, nutritional therapy is recommended to achieve euglycemia or blood-glucose balance. It's important to ensure appropriate weight gain, but not weight loss, and adequate nutritional intake for mother and baby. If reductions in blood glucose do not reach the recommended levels within two weeks after eating and exercise adjustments, then certain types of insulin can be safely used in pregnancy.
Because women with a history of gestational diabetes risk developing type 2 diabetes later in life, a follow-up blood glucose test is recommended within six months of childbirth. In addition, it is recommended that women breastfeed to reduce the risk for subsequent diabetes in the baby. Women should be screened regularly for type 2 diabetes.
Complications: Babies born to mothers with gestational diabetes may be macrosomic (severely obese). This poses a risk of trauma to mother and child during childbirth.
Macrosomic babies have a higher risk of severe breathing problems and hypoglycemia (severely low blood glucose levels) after birth. They are also at higher risk for potential long-term obesity and glucose intolerance. Generally, glucose levels in women who have had GDM return to normal.
However, these women do face an increased risk of developing type 2 diabetes later in life.
Sources: Canadian Diabetes Association, Centers for Disease Control, National Diabetes Information Clearinghouse / Compiled by Marian Traynor and Peggy Mackenzie, Toronto Star Library.