Although mass screening remains controversial, regular assessment of risk factors and targeting individuals with established risk is clearly indicated (PATIENT HANDOUT). The importance of early detection was highlighted by the United Kingdom Prospective Diabetes Study, in which approximately half of the patients with newly diagnosed type 2 diabetes already had evidence of complications.9
TABLE
Type 1, type 2, and gestational diabetes: Diagnostic clues
| TYPE 1 DIABETES | TYPE 2 DIABETES | GESTATIONAL DIABETES MELLITUS (GDM) | |
|---|---|---|---|
| Risk factors/characteristics | Patient/family history of autoimmune disease 1st-degree relative with type 1 diabetes Normal weight with symptoms of hyperglycemia | BMI ≥25 Physical inactivity 1st-degree relative with type 2 diabetes High-risk ethnic group (African American, Hispanic, Native American, Asian American, Pacific Islander) History of GDM and/or delivery of an LGA infant BP >135/80 mm Hg or being treated for HTN Polycystic ovary syndrome IGT or IFG Acanthosis nigricans | BMI ≥30 History of GDM and/or delivery of an LGA infant (or poor outcome) 1st-degree relative with type 2 diabetes High-risk ethnic group (African American, Hispanic, Native American, Asian American, Pacific Islander) Glycosuria Age >25 years Polycystic ovary syndrome IGT |
| Laboratory tests/positive results | Specific antibodies to islet cell, insulin, and/or GAD* Tyrosine phosphatase-like auto antigen IA-2 (marker of autoimmune islet cell disease) C-peptide (low or absent); if in normal range, may indicate early disease and partial β-cell activity | FPG >126 mg/dL Random plasma glucose >200 mg/dL (test repeated next day) 2-hr 75-g OGTT >200 mg/dL HDL <35 mg/dL TG >250 mg/dL C-peptide (normal or elevated; may be low initially due to glucose toxicity) | Fasting: ≥95 mg/dL 1-hr OGTT: ≥180 mg/dL 2-hr OGTT: ≥155 mg/dL 3-hr OGTT: ≥140 mg/dL |
| BMI, body mass index; BP, blood pressure; DM, diabetes mellitus; FPG, fasting plasma glucose; GAD, glutamic acid decarboxylase; HDL, high-density lipoproteins; HTN, hypertension; IFG, impaired fasting glucose; IGT, impaired glucose tolerance; LGA, large for gestational age; OGTT, oral glucose tolerance test; TG, triglycerides. | |||
| *GAD65 is most specific. | |||
DIABETES PREVENTION PATIENT HANDOUT: Get healthier, one small step at a time
Eating well, maintaining your weight, and engaging in physical activity are essential to good health. If you have risk factors for diabetes, diet and exercise are important steps you can take to help keep the disease at bay.
Making changes to your diet and increasing the amount of exercise you engage in need not be a daunting task. It helps to remember that it’s not necessary to take giant steps. You can improve your health and help prevent diabetes with a series of small changes. For best results, keep each goal small, manageable, and as specific as possible.
Eating. Do you eat fast food frequently, or snack on ice cream or potato chips when you watch TV at night? Pick a “bad habit” that is of particular concern and try to “turn it around.” You might, for instance, promise yourself that:
For the next 4 weeks, I will replace my unhealthy evening snacks with fresh fruit, a small bowl of cereal, or (insert another healthy snack here).
Getting active. Have you stopped working out? Are you concerned that working out will require a big time commitment? Think again. Start small and promise yourself that:
For the next 3 weeks, I will take a 20-minute walk 3 mornings a week.
Each time you set a goal, monitor your progress. When you succeed, give yourself a reward—it can be something as simple as a long bath or a trip to the movies—and vow to continue that lifestyle change and to add another. If you aren’t successful, think about why and revise your goal. If you find you’re too busy getting the kids off to school to walk in the morning, for example, change your schedule and start going out during your lunch break. Or, if it’s too cold or rainy, find a nearby mall where you can walk (or a treadmill at a local gym) instead. It also helps to get a step counter, or pedometer. The American Diabetes Association (ADA) recommends taking 10,000 steps per day.
For additional ideas, visit the ADA Web site (www.diabetes.org) and click on Fitness. Or call our office at __________ and make an appointment to come in and discuss additional lifestyle changes—small and large—that you can make with our help.
Validated risk calculators can boost detection rates
In an attempt to improve detection rates of type 2 diabetes and prediabetes, researchers in both the United States and the United Kingdom recently developed easy-to-use risk calculation tools. The Diabetes Risk Calculator (available at http://www.diabetes.org/food-nutrition-lifestyle/lifestyle-prevention/risk-test.jsp), published in 2008, was validated with findings from the Third National Health and Nutrition Survey.10 The calculator uses answers to questions about age, waist circumference, history of gestational diabetes mellitus (GDM), height, race/ethnicity, hypertension, family history, and exercise to determine whether an individual is at high risk for undetected diabetes. The tool has a low positive predictive value (14%), but a negative predictive value >99%.10
The QDScore Diabetes Risk Calculator (www.qdscore.org), another new tool, is designed to estimate an individual’s 10-year risk of developing type 2 diabetes.11 The program, which calculates risk based on answers to questions about family history of diabetes, patient history of cardiovascular disease, smoking, treatment for hypertension, BMI, ethnicity, and steroid use, was validated with data collected from 2.5 million patients in practices throughout England and Wales. The screening tool showed a high degree of discrimination in reflecting differences in disease prevalence related to ethnic and socioeconomic risk factors.11