Introduction.
Diabetes has few subjective symptoms in the early stages. Many people are detected when they are told that their blood glucose level is high during a physical checkup or that their HbA1c is slightly elevated.
However, diabetes is not a disease that should be looked at only by blood glucose levels. A comprehensive combination of blood tests, urinalysis, and imaging tests for complications is important to determine the diagnosis and treatment plan.
This article details the typical tests for diabetes, what they mean, and when to take them.
1. basic diabetes test (blood test)
(1) Fasting plasma glucose (FPG)
- Blood glucose measured without eating for more than 8 hours
- Diabetes is strongly suspected above 126 mg/dL
Because blood glucose levels fluctuate from day to day, it can be difficult to determine a single value alone. Retests and HbA1c are important in combination.
(2) Blood glucose level at any time
- Convenient test that can be taken after meals or at any time during the day
- Diabetes can be diagnosed with 200 mg/dL or more + symptoms
This is a good opportunity for early detection because it can be "checked on the spot" during physical examinations or as an outpatient.
(3) HbA1c (hemoglobin A1c)
- Indicator reflecting average blood glucose over the past month or two
- Determined as diabetic type at 6.51 TP3T or higher
- Errors can occur due to anemia, kidney damage, etc., and are determined in conjunction with other blood glucose levels.
HbA1c is not affected by diurnal variation and is essential for the diagnosis and follow-up of diabetes.
(4) OGTT (Oral glucose tolerance test)
- Measure blood glucose 2 hours after drinking glucose (75 g)
- Diabetic type with blood glucose of 200 mg/dL or more after 2 hours
It is useful when postprandial hyperglycemia is suspected or to confirm borderline (pre-pregnant) type.
2. urinalysis - early detection of complications by urinary sugar and protein
In diabetes, high blood sugar levels cause sugar to leak into the urine.
(1) Urinary sugar
- If there is sugar in the urine, be careful.
- May appear after eating or during stress, and must be checked in conjunction with blood tests
(2) Urinary albumin and urinary protein
- Indicators for early detection of kidney damage
- If trace albuminuria is present, it may be the beginning of diabetic nephropathy
Ikejiri-Ohashi Sera Clinic performs periodic urine albumin tests to evaluate renal function at an early stage.
3. imaging and functional tests for complications
Diabetes is not a "blood sugar disease" but rather a "vascular disease.
Because persistent high blood sugar can damage **small blood vessels (microvascular disease) and large blood vessels (macrovascular disease)**, the following tests are also performed.
(1) Fundus examination
- Early detection of diabetic retinopathy by direct observation of retinal blood vessels
- We use fundus camera imaging and evaluation, which is rare outside of ophthalmology
(2) ABI (ankle-brachial index)
- Evaluate progression of arteriosclerosis
- Early detection of "arteriosclerosis obliterans" with poor blood flow in the legs
(3) Carotid artery echocardiography
- Check for vessel wall thickness and plaque to determine stroke risk
(4) Holter ECG
- 24-hour ECG recordings to check the effects of arrhythmias and autonomic nervous system disorders
At Ikejiri-Ohashi Sera Clinic, diabetes testing is not limited to blood glucose levels alone, but also includes comprehensive evaluation of blood vessels, nerves, and kidneys.
4. guidelines for diabetes screening (medical checkup) and retesting
Fasting blood glucose and HbA1c are often checked during physical examinations.
- Fasting blood glucose 110-125 mg/dL
- HbA1c between 5.7 and 6.41 TP3T
If the patient has pre-diabetes (borderline diabetes), regular follow-up is recommended.
Many people can prevent the onset of diabetes by adjusting their lifestyle at this stage.
5. frequency of testing and follow-up
If diabetes is suspected or being treated, the following frequency of testing is recommended
- HbA1c: every 1-3 months
- Blood glucose: per hospital visit (if necessary)
- Urinalysis (albumin): once or twice a year
- Fundus examination: once a year
- ABI and carotid echocardiography: depending on risk of complications
6. examination system at Ikejiri-Ohashi Sera Clinic
We offer a full range of services from diagnosis to evaluation of complications of diabetes mellitus.
- Same-day blood glucose and HbA1c measurements
- In-hospital completion of fundus, ABI, and carotid echocardiography
- Diabetes Specialist + Exercise Therapy Program + Cross-Cutting Treatment with Medical Diet
- Simultaneous evaluation of association with MASLD (fatty liver), hypertension, and dyslipidemia
We offer an examination schedule tailored to each patient and focus on **"protecting blood vessels "**, not just "lowering numbers".
summary
- It is important to test for diabetes using a combination of blood glucose, HbA1c, urine, and complication evaluation.
- HbA1c reflects average blood glucose and is essential for diagnosis and follow-up.
- Early detection of vascular and renal risks with urine albumin, fundus examination, ABI, carotid echocardiography, etc.
- Ikejiri-Ohashi Sera Clinic comprehensively diagnoses, evaluates, and improves overall lifestyle-related diseases including diabetes.
References
- The Japan Diabetes Society. Diabetes Care Guide 2024-2025.
- American Diabetes Association. Standards of Care in Diabetes 2024. Diabetes Care.
- International Diabetes Federation. IDF Diabetes Atlas 10th Edition, 2023.
- The Japan Diabetes Society. Guidelines for the Evaluation of Diabetic Nephropathy and Retinopathy, 2023.
Diabetes Series - Related Article List
1. Know the basics of diabetes
- What is Diabetes - Why does blood sugar rise? Causes and Mechanisms Explained
Introduces the root causes of diabetes, including "insulin resistance," "heredity," and "lifestyle," which are all related to the development of diabetes, in an easy-to-understand manner. - Early Symptoms of Diabetes - Don't Miss the Early Detection Signs
Early signs that are difficult to recognize, such as thirst, polyuria, and weight loss, are carefully explained. - Diagnostic criteria for diabetes - Difference between HbA1c, blood glucose and OGTT and latest criteria
It summarizes the numerical values used for diagnosis and the key points of the recently revised diagnostic criteria. - Diabetes Testing - Comprehensive evaluation of blood, urine, and even complications
Introduction to the comprehensive examination system available at the Ikejiri-Ohashi Sera Clinic, including fundus examination, ABI, and carotid artery echocardiography.
2. Treatment and lifestyle modification
- Diabetes Treatment - Protecting Blood Sugar and Blood Vessels with Diet, Exercise, and Medication
Explains treatment strategies to "prevent complications" rather than "lower the numbers. - Diabetes Diet - Control Blood Sugar Effortlessly with Locavore
A practical diet that emphasizes how to eat, not what not to eat. - Diabetes and Exercise - Muscle is Medicine! The Science of Aerobic x Muscle Training
The benefits of exercise to directly lower blood sugar and how to create an easy to follow exercise routine. - Drug Therapy for Diabetes Mellitus - Latest Treatment Policies and Multi-Drug Approaches
The characteristics of DPP-4 inhibitors, SGLT2 inhibitors, and GLP-1 agonists are compared, and the latest treatment trends are presented.
3. To prevent complications
- Complications of diabetes - Complication measures to remember with "shimeji" and "enoki" mushrooms
The six major complications of neuropathy, retinopathy, nephropathy, gangrene, stroke, and cardiac disease are explained together. - Neuropathy due to diabetes - Mechanisms and countermeasures for numbness and pain in hands and feet
Early signs of peripheral neuropathy and ways to improve life that should be done early. - Diabetes and Renal Dysfunction - Importance of Urine Albumin Testing and Habits to Protect
Practical approaches to reduce the burden on the kidneys and prevent dialysis. - Diabetes and Eye Disease - Causes of Blurred Vision and Early Detection of Retinopathy
Explains how fundus camera examinations work and the risks of neglect.
4. Prevention and early intervention
- Prevention of Diabetes - Reduce blood sugar waves and make your body less prone to diabetes.
Introduces diet, exercise, and sleep regimens to "get in shape before it happens," rather than "fix it after it happens. - Characteristics and constitution of people prone to diabetes - Self-check that you can do now
Early intervention is recommended by sorting out the risk of developing the disease, including heredity, fatty liver, and lack of exercise.
5. Our features and support system
- Lifestyle-related disease treatment at Ikejiri-Ohashi Sera Clinic - Cross-cutting management of diabetes, MASLD, hypertension and dyslipidemia
Includes a comprehensive evaluation system including physician supervised exercise therapy, locavore diet support, fundus, ABI, and carotid artery echocardiography.