Introduction
Diabetes Mellitus (DM) is a chronic metabolic disorder characterized by persistent elevation of blood glucose levels due to defects in insulin secretion, insulin action, or both. Insulin is a hormone produced by the pancreas that helps glucose enter body cells to be used for energy. When insulin is deficient or ineffective, glucose accumulates in the bloodstream, leading to hyperglycemia.
Diabetes affects the metabolism of carbohydrates, fats, and proteins. If uncontrolled over time, it can damage multiple organs including the heart, kidneys, eyes, nerves, and blood vessels. It is one of the leading causes of morbidity and mortality worldwide and has become a major public health challenge due to increasing sedentary lifestyles, obesity, and unhealthy dietary patterns.
Burden of Diabetes
Global Burden
Diabetes currently affects hundreds of millions of adults worldwide. Approximately 537 million adults aged 20–79 years are living with diabetes globally. Nearly half of these individuals remain undiagnosed, increasing the risk of delayed treatment and complications. Diabetes is a major contributor to cardiovascular disease, kidney failure, blindness, and premature death.
Indian Burden
India has one of the largest diabetes populations in the world, with around 101 million people affected. Adult prevalence is estimated at 11–12%. In addition, nearly 15% of the population has prediabetes, placing them at high risk of progressing to diabetes in future. Urban populations show higher prevalence than rural areas, although rural prevalence is also rising rapidly. Alarmingly, diabetes is increasingly seen in younger age groups in India.
Signs and Symptoms
The classical symptoms of diabetes are known as the three Ps:
- Polyuria – frequent urination
- Polydipsia – excessive thirst
- Polyphagia – excessive hunger
Other common symptoms include:
- Unexplained weight loss
- Fatigue and weakness
- Blurred vision
- Slow wound healing
- Recurrent infections such as skin infections, urinary tract infections, and fungal infections
- Tingling or numbness in hands and feet
Many individuals with type 2 diabetes may remain asymptomatic in the early stages, making screening essential.
When to Suspect Diabetes
Diabetes should be suspected in the following situations:
- Adults aged 30 years or more with risk factors
- Presence of classical symptoms
- Random blood glucose ≥200 mg/dL
- Recurrent infections or delayed wound healing
- Positive family history of diabetes
- Unexplained weight loss
- Obesity or central obesity
Early suspicion leads to timely diagnosis and prevention of complications.
Importance of Diabetes Screening
Screening is essential because many individuals remain asymptomatic during the early stage of disease.
Benefits of screening include:
- Early detection of diabetes
- Identification of prediabetes
- Prevention of complications such as kidney disease, retinopathy, stroke, and heart disease
- Reduction in hospitalization and healthcare expenditure
- Better quality of life through timely lifestyle modification and treatment
Screening is especially useful in high-risk populations.
Who Should Be Screened
Adults aged 30 years and above should undergo screening, particularly if one or more risk factors are present.
High-risk groups include:
- Overweight or obese individuals
- Persons with family history of diabetes
- Hypertensive individuals
- Sedentary workers
- Women with history of gestational diabetes
- Persons with abdominal obesity
- Individuals with unhealthy diet habits
Screening and Confirmatory Tests
Screening Tests
- Random Blood Glucose (RBG)
- Urine Glucose Test
Confirmatory Tests
- Fasting Blood Glucose (FBG)
- Oral Glucose Tolerance Test (OGTT)
- HbA1c Test
These tests help establish diagnosis and assess long-term glycemic control.
Steps of Checking Capillary Blood Glucose at Home
- Wash hands with soap and water and dry properly.
- Insert test strip into glucometer.
- Clean fingertip with alcohol swab and allow to dry.
- Use lancet to prick side of fingertip.
- Allow a drop of blood to touch the strip.
- Wait for result to appear on screen.
- Record the glucose reading.
Self-monitoring helps maintain better glycemic control.
Diagnostic Criteria for Diabetes Mellitus
| Test | Diagnostic Value |
|---|---|
| Fasting Plasma Glucose | ≥126 mg/dL |
| Random Blood Glucose with symptoms | ≥200 mg/dL |
| OGTT | ≥200 mg/dL |
| HbA1c | ≥6.5% |
These criteria are recommended by major international guidelines.
Urine Sugar Examination (Dipstick Method)
Procedure:
- Collect fresh midstream urine in a clean container.
- Dip strip for 1–2 seconds.
- Remove excess urine.
- Wait 30–60 seconds.
- Compare color with standard chart.
Repeated positive urine sugar should be followed by blood glucose testing. It is mainly useful as a community-level screening tool.
Risk Factors of Diabetes
Non-Modifiable
- Increasing age
- Family history
- South Asian ethnicity
- History of gestational diabetes
Modifiable
- Obesity
- Physical inactivity
- Unhealthy diet
- Tobacco use
- Alcohol excess
- Chronic stress
Family History
Risk is higher among first-degree relatives such as parents, siblings, and children because they share nearly 50% genetic similarity. Individuals with diabetic parents should undergo earlier and more frequent screening.
Obesity
Obesity causes insulin resistance and is a major modifiable risk factor.
Indian Criteria
- BMI ≥25 kg/m² = Obese
- Waist circumference >90 cm in men
- Waist circumference >80 cm in women
Even 5–10% reduction in body weight can significantly reduce diabetes risk.
Body Mass Index (BMI)
BMI=\frac{Weight\ (kg)}{Height\ (m)^2}
Asian Classification
| BMI | Category |
|---|---|
| <18.5 | Underweight |
| 18.5–22.9 | Normal |
| 23–24.9 | Overweight |
| ≥25 | Obese |
Physical Activity
Physical inactivity increases insulin resistance.
Recommendation:
- 150 minutes/week moderate activity minimum
- Prefer 30 minutes brisk walking/day for 5 days/week
- Add resistance exercise 2–3 days/week
Regular exercise reduces diabetes risk by 30–40%.
Unhealthy Diet
Risk increases with:
- High sugar intake
- Refined carbohydrates
- Saturated fat rich foods
- Low fiber intake (<25 g/day)
Protective diet includes:
- Vegetables 400–500 g/day
- Whole grains
- Pulses
- Nuts in moderation (20–30 g/day)
- Fruits 2 servings/day
Tobacco and Alcohol
Tobacco increases insulin resistance and vascular damage.
Alcohol, if consumed, should be limited. Excess alcohol causes glucose fluctuations and increases complications risk. Avoid alcohol in uncontrolled diabetes.
Indian Diabetes Risk Score (IDRS)
IDRS is a simple screening tool using:
- Age
- Waist circumference
- Physical activity
- Family history
Interpretation
- <30 = Low risk
- 30–50 = Moderate risk
- ≥60 = High risk
Useful in Indian community screening programs.
Complications of Diabetes
Major complications include:
- Retinopathy – blindness risk
- Nephropathy – kidney damage
- Neuropathy – numbness, burning feet
- Coronary artery disease / Stroke
- Diabetic foot ulcers / gangrene
These complications are preventable with good control.
Prevention of Complications
Blood Sugar Targets
- HbA1c <7% (individualized)
- Fasting glucose often 80–130 mg/dL
- Post meal <180 mg/dL
Lifestyle
- Walk 30–45 min/day
- Sleep 7–8 hours/day
- Avoid smoking
- Maintain BMI 18.5–23 kg/m²
- Foot inspection daily
Screening
- Eye examination yearly
- Kidney urine albumin yearly
- Foot exam yearly
- Blood pressure every visit
Recommended Diet for Diabetes
Daily Intake
- Vegetables: 4–5 servings/day
- Fruits: 2 servings/day
- Whole grains: 6 servings/day
- Pulses/legumes: 2 servings/day
- Low-fat milk/curd: 1–2 servings/day
- Water: 2.5–3.5 liters/day unless medically restricted
Foods to Limit
- White rice
- Maida products
- Sugary tea/coffee
- Soft drinks
- Cakes, biscuits, sweets
- Fried fast foods
Foods to Prefer
- Brown rice / millets / oats
- Whole wheat roti
- Dal, chana, rajma
- Green leafy vegetables
- Guava, apple, orange
- Unsweetened buttermilk
Conclusion
Diabetes Mellitus is a rapidly growing chronic disease with serious health consequences. However, early screening, timely diagnosis, regular exercise, healthy eating, weight control, and medication adherence can effectively prevent complications and improve quality of life. Public awareness and community-based prevention strategies are essential to reduce the burden of diabetes, especially in countries like India.
MCQs
1. The most sensitive test for diagnosing long-term glycemic status over the previous 3 months is:
A. Random blood glucose
B. Fasting plasma glucose
C. HbA1c
D. Urine glucose
Answer: C. HbA1c
2. A patient with fasting plasma glucose of 132 mg/dL on repeat testing is classified as:
A. Normal
B. Prediabetes
C. Diabetes mellitus
D. Impaired glucose tolerance
Answer: C. Diabetes mellitus
3. Classical triad of symptoms in uncontrolled diabetes includes:
A. Polyuria, polydipsia, polyphagia
B. Fever, weight gain, edema
C. Cough, thirst, sweating
D. Headache, vomiting, diarrhea
Answer: A. Polyuria, polydipsia, polyphagia
4. According to Asian BMI criteria, overweight is defined as:
A. BMI 18.5–22.9
B. BMI 23–24.9
C. BMI 25–29.9
D. BMI >30
Answer: B. BMI 23–24.9
5. Obesity in Indians is diagnosed at BMI:
A. ≥23 kg/m²
B. ≥24 kg/m²
C. ≥25 kg/m²
D. ≥30 kg/m²
Answer: C. ≥25 kg/m²
6. Waist circumference indicating central obesity in Indian males is:
A. >80 cm
B. >85 cm
C. >90 cm
D. >100 cm
Answer: C. >90 cm
7. Which one is a non-modifiable risk factor for type 2 diabetes?
A. Tobacco use
B. Sedentary lifestyle
C. Family history
D. High-fat diet
Answer: C. Family history
8. First-degree relatives share approximately what proportion of genes?
A. 25%
B. 50%
C. 75%
D. 100%
Answer: B. 50%
9. Which of the following is a confirmatory test for diabetes?
A. Urine glucose
B. HbA1c
C. Urine ketones
D. Serum creatinine
Answer: B. HbA1c
10. Random blood glucose diagnostic of diabetes in symptomatic patient is:
A. ≥126 mg/dL
B. ≥140 mg/dL
C. ≥180 mg/dL
D. ≥200 mg/dL
Answer: D. ≥200 mg/dL
11. Which complication is correctly matched with diabetes?
A. Retinopathy – Liver failure
B. Neuropathy – Burning feet
C. Nephropathy – Cataract
D. CAD – Pneumonia
Answer: B. Neuropathy – Burning feet
12. Recommended minimum moderate physical activity per week for diabetes prevention:
A. 60 min/week
B. 90 min/week
C. 150 min/week
D. 300 min/week mandatory
Answer: C. 150 min/week
13. In Indian Diabetes Risk Score (IDRS), score ≥60 indicates:
A. Low risk
B. Moderate risk
C. High risk
D. Confirmed diabetes
Answer: C. High risk
14. Which parameter is NOT included in IDRS?
A. Age
B. Waist circumference
C. Physical activity
D. HbA1c value
Answer: D. HbA1c value
15. A patient with long-standing diabetes develops frothy urine and pedal edema. Most likely complication is:
A. Retinopathy
B. Nephropathy
C. Neuropathy
D. Stroke
Answer: B. Nephropathy
16. Preferred cereal in diabetic diet is:
A. White bread
B. Polished rice
C. Maida naan
D. Oats
Answer: D. Oats
17. Which fruit is generally preferred over high glycemic index fruits in diabetes?
A. Ripe banana
B. Pineapple
C. Apple
D. Watermelon
Answer: C. Apple
18. Target HbA1c for many non-pregnant adults to prevent complications is approximately:
A. <5%
B. <6%
C. <7%
D. <9%
Answer: C. <7%
19. Urine glucose testing in community settings is mainly useful as:
A. Definitive diagnostic test
B. Screening tool
C. Test for nephropathy
D. Measure insulin resistance
Answer: B. Screening tool
20. A diabetic patient complains of numbness and tingling of feet. Most likely cause:
A. Peripheral neuropathy
B. Retinopathy
C. Nephropathy
D. Myopathy
Answer: A. Peripheral neuropathy
