Diabetes mellitus (Diabetes mellitus)
1) Disease description (causes and symptoms)
- Causes and pathophysiology
- This is a metabolic disease in which blood glucose remains elevated due to insufficient secretion of insulin produced by the pancreas or reduced insulin action. When blood glucose is high, glucose is excreted in the urine, causing water loss, electrolyte imbalance, and metabolic abnormalities.
- Both genetic predisposition and environmental factors are involved in its development. Risk factors include older age, obesity (especially abdominal obesity), lack of exercise, stress, pregnancy, infection, and exposure to medications such as steroids and immunosuppressants. Cases in which a specific genetic abnormality is identified are rare (a small minority of all cases).
- Main symptoms
- The classic three polys: polyuria, polydipsia, and polyphagia
- Fatigue, weight loss (despite maintaining food intake), visual disturbances (reduced vision), numbness or tingling in the hands and feet (neuropathy), and itchy skin (especially vaginal itching in women)
- Mild cases or cases in the early chronic stage are often asymptomatic
- Overview of complications (related to pathophysiology)
- Acute metabolic complications: hyperglycemic coma (hyperosmolar state), ketoacidosis, severe hypoglycemia, etc. — immediate treatment is required
- Chronic complications: lesions of the microvasculature (retinopathy, nephropathy, and neuropathy) and macrovasculature (cardiovascular disease, cerebrovascular disease, and peripheral artery disease). Vascular damage progresses as a result of long-term hyperglycemia.
2) Treatment methods and precautions
- Basic principles
- Lifestyle management (dietary therapy + regular exercise) → medication if necessary (oral hypoglycemic agents) → insulin (or injectable medications), with treatment provided stepwise and individualized
- Medication treatment (summary)
- Oral medications: metformin (recommended first-line medication), SGLT2 inhibitors, GLP-1 analogues (including injectable medications), DPP-4 inhibitors, sulfonylureas, etc. — selected according to patient characteristics (renal function, body weight, and concomitant cardiovascular or kidney disease)
- Insulin: used for type 1 diabetes or when control is insufficient with oral medications, and in cases of acute complications, surgery, pregnancy, etc.
- Monitoring and targets (general recommendations)
- The HbA1c target is individualized according to patient characteristics (generally, a target around 7% is used, but the target is relaxed for older adults and patients at risk of hypoglycemia)
- Self-monitoring of blood glucose (using a blood glucose meter), regular HbA1c testing (generally every 3 months when adjusting treatment, and every 3–6 months when stable), and periodic tests such as renal function, lipid, and urine albumin tests are necessary
- Management of comorbidities (important for reducing cardiovascular risk)
- Controlling blood pressure and lipids (hyperlipidemia) is important for preventing coronary artery and cerebrovascular complications
- Education and self-management precautions
- Recognize and manage hypoglycemia (symptoms and rapid intake of sugar), manage sick days, regularly inspect the feet and skin (foot care), and undergo regular fundus examinations (for retinopathy) and kidney tests
- Check for medication side effects (e.g., hypoglycemia, gastrointestinal symptoms, and SGLT2-related urinary tract infections) and drug interactions
- Emergencies
- Visit the emergency room immediately in the event of severe vomiting, dehydration, confusion, or decreased consciousness (ketoacidosis or hyperosmolar coma may be present)
3) Checklist before an outpatient visit (items to bring and interview preparation)
- Items to bring (recommended)
- A list of all medications and supplements currently being taken (name, dose, and administration time)
- Recent test results (HbA1c, fasting blood glucose, renal function (BUN/Cr), electrolytes, lipids, and urine albumin/creatinine ratio from within the past 3–6 months)
- Self-monitored blood glucose records (measurements by time of day, including records of hypoglycemia)
- A record of changes in symptoms (changes in weight, urination, thirst, fatigue, and vision, etc.), and any recent infections, surgery, or stressful situations
- Photos of the feet (if there are wounds, blisters, or redness on the feet), and whether pregnancy is possible (women of childbearing age)
- Information that is helpful to provide to the medical staff during an outpatient visit
- Regular eating and exercise patterns, alcohol consumption and smoking status, and family history (diabetes, cardiovascular disease, etc.)
- History of recent hospitalizations or emergency room visits
Example questions (in a form that patients can answer immediately during an outpatient visit)
- Recent self-monitored blood glucose patterns (fasting in the morning, 2 hours after meals, before bedtime, etc.) and whether hypoglycemia has occurred
- The names and doses of medications currently being taken
4) Examples of general questions to ask the doctor
- What are the most common side effects of this medication (or combination of medications), and how should they be managed?
- What should my target HbA1c (or blood glucose range) be? How is an individualized target determined?
- What are specific ways to prevent and manage hypoglycemia?
- How often should I be screened for complications (eyes, kidneys, nerves, feet, etc.)?
- How should hypertension and hyperlipidemia accompanying diabetes be managed in an integrated manner?
5) Examples of disease-specific customized questions
- I am planning a pregnancy. Do my blood glucose targets and medications (especially oral medications and insulin) need to be adjusted before and during pregnancy?
- I have recently experienced reduced sensation in my feet. How should foot examinations (sensation, blood flow, and wounds) and foot care be managed?
Note: Diagnostic criteria (for clinical reference) — Diabetes mellitus may be diagnosed when, in the presence of clinical symptoms, at least one of the following is met: random blood glucose ≥ 200 mg/dL, fasting blood glucose ≥ 126 mg/dL (8 hours of fasting), or 2-hour blood glucose ≥ 200 mg/dL after a 75 g oral glucose tolerance test. When there are no clear symptoms of hyperglycemia, confirmation with repeat testing on another day is recommended.