2In the Indian context, increasing urbanization, industrialisation and changing lifestyles seem to be contributing to increasing prevalence of diabetes.
With over 3.5 crore persons with diabetes in India, it is indeed a disease to reckon with. Prevalence of type 2 diabetes has been steadily increasing in urban areas to a 14% in 2000 in the adult population. There is an equally large pool of persons with impaired Glucose Tolerance (IGT), many of whom will go on to develop type 2 diabetes in the near future. In fact, WHO has estimated that the number is likely to be 5.72 crore by 2025. The rapid increase in population, increased longevity and high ethnic susceptibility to diabetes, coupled with rapid urbanization and changes from traditional lifestyles will most likely trigger a diabetes epidemic and it has been reported that every fifth patient visiting a consulting physician and every seventh patient visiting a family physician has diabetes. India has now been declared by WHO as the diabetes capital of the world.
However, based on sales of anti-diabetic drugs, it is estimated that a meagre 10–12% of the diabetic population receive modern pharmacological treatment as of today. Inadequate information on this subject always acts as a hindrance to the accurate diagnosis and treatment of diabetes.
The choice of treatment and patient compliance is important for metabolic control to be achieved by the diabetic patient.3
While diet, exercise and oral drugs are useful in controlling diabetes in many patients, it is now recognised that a large number of Type 2 patients require insulin therapy. This could be due to oral drugs failing to provide good metabolic control during special situations like pregnancy, surgery infections, etc. In order to provide accurate information on diabetes, a comprehensive guide has been designed to serve as a ready reckoner for diabetes.
Definition
Diabetes mellitus is a syndrome characterised by chronic hyperglycaemia and disturbances of carbohydrate, fat and protein metabolism associated with absolute or relative deficiency in insulin secretion and/or insulin action. Insulin allows glucose (sugar) to enter body cells to convert it into energy. Insulin is also needed to synthesize protein and store fats. In uncontrolled diabetes, glucose and lipids (fats) remain in the bloodstream and, with time damage the body's vital organs and contribute to heart disease.
Classification
Diabetes is classified into three main types:
- Type 1 previously called insulin-dependent diabetes mellitus (IDDM)
- Type 2 previously called non-insulin-dependent diabetes mellitus (NIDDM)
- Gestational diabetes mellitus (GDM).
Type 1 Diabetes
Occurrence
- Scientists do not know exactly what causes the body's immune system to attack the β-cells, but they believe that both genetic factors and environmental factors and possibly viruses, are involved.
Characteristics
- Often develops in children and young adults, but the disorder can appear at any age.
- Symptoms usually develop over a short period, although β-cell destruction can begin years earlier.
- If not diagnosed and treated with insulin, a person can lapse into a life-threatening diabetic coma, also known as diabetic ketoacidosis.
Type 2 Diabetes
Occurrence
- The most common form of diabetes.
- Due to reduced insulin secretion or peripheral resistance to action of insulin.
- The result is the same as for Type 1 diabetes, glucose builds up in the blood and the body cannot make efficient use of its main source of fuel.
- Often part of a metabolic syndrome that includes obesity, elevated blood pressure, and high levels of blood lipids.
Characteristics
- This form of diabetes usually develops in adults.
- About 80 percent of people with Type 2 diabetes are overweight.
- Increase in incidence of childhood obesity leads to Type 2 diabetes becoming more common in young people.
Symptoms and Management for Type 1 and Type 2 Diabetes
Symptoms
- Increased thirst and urination
- Constant hunger
- Weight loss
- Blurred vision
- Extreme fatigue
- Slow healing of wounds or sores
Management
- Diet
- Exercise
- Insulin for Type 1 and OHAs or insulin for Type 2
- Education
- Monitoring blood glucose and therapy.
Gestational Diabetes
Occurrence
- Insulin resistance due to pregnancy.
- Genetic predisposition.
Management
- Diet: Provide adequate calories which will not lead to hyperglycaemia or ketonaemia
- Exercise: That does not cause fetal distress, contractions or hypertension.
- Insulin; to maintain blood glucose, fasting < = 95 mg/dl (<= 5.3 mmol/l); one hour postprandially and two hour postprandially and two hour postprandially < = 120 mg/dl (< = 6.7 mmol/l).
Glycated Hemoglobin (HbA1c) Test
- Indicates blood glucose control over a period of approximately 3 months.
- Normal range varies depending on the method the lab uses: usually 4–7%, correlating to average blood glucose of 60–150 mg/dl (3.3.-8.3 mmol/l).
- Should be prescribed by health care provider every 3 months for Type 1 diabetes and at 3–6 month intervals for Type 2, to help determine overall control.
- Patient does not need to be fasting to have this blood test performed.
Ketone Test
Ketone is by product of fat metabolism; presence of ketones indicates that the body is not metabolizing food properly because of lack of available insulin or carbohydrate; may indicate impeding or established diabetic 7ketoacidosis (DKA), a condition that requires immediate medical attention.
Method: Dipstick
When to Test
- When blood glucose level is consistently > 300 mg/dl (16.7 mmol/l).
- During periods of acute illness (illness is a stress that can cause hyperglycaemia).
- When symptoms of hyperglycaemia accompanied by nausea, vomiting and abdominal pain are present.
Goals of Treatment
- Control high blood glucose (hyperglycaemia)
- Avoid low blood glucose (hypoglycaemia).
- Treatment of associated conditions, such as high blood pressure, cholesterol disorder and obesity.
- Prevent or retard the progression of complications of diabetes such as blindness, kidney failure, heart disease, stroke and amputation of legs.
Treatment Plan
Management of Blood Glucose
Target Blood Glucose Values
(as recommended by the American Diabetes Association)
Pre-meal blood glucose | 80–120 mg/dl |
Bedtime blood glucose | 100–140 mg/dl |
*HbA1c | Less than 7% |
*With an upper limit of normal range = 6.0%. The normal range for this test varies from laboratory to laboratory. | |
However, not every person is a candidate for such tight blood glucose control. This should not be attempted in:
- Frail, elderly persons who have already developed the complications of diabetes such as blindness and end-stage kidney failure.
- Elderly patients having frequent low blood glucose episodes.Exercise can improve the health and outlook of life. Regular and controlled exercise not only helps to increase glucose utilization but also helps to maintain desirable health.
Do's in Exercise
- Check the patients for blood pressure, blood fat levels, HbA1, health of heart, circulatory and nervous systems, kidney function, eyes and feet.
- Choose exercises that fit the patient's health.
- Exercise should be preceded and followed by 5–10 minutes of slow, continuous, aerobic activities.
- Remember the feet. Advise them to wear the comfortable shoes for the sport.
- Watch for low blood sugar, insulin or oral diabetes medicine may lead to low blood sugar levels.
- Advice the patient to keep a snack handy to avoid low blood sugar levels during the exercise.
Don'ts in Exercise
- Advise not to snack unnecessarily before exercise.
- Uncomfortable shoes should not be worn while exercising.
- Avoid exercising in extreme cold or heat.
- Exceeding target heart rate of 60 to 80% of estimated maximum heart rate.
Oral hypoglycaemic agents (OHAs) are primarily used in Type 2 diabetes adjunct to nutrition therapy and exercise.
Oral agents are broadly classified as follows:
First Generation Sulfonylureas
Generic name | Dosage range per day | Duration of action | Side effects of class |
|---|---|---|---|
Chlorpropamide | 100–500 mg | > 48 hrs | Prolonged hypoglycaemia, cholestatic jaundice, hypersensitivity; alcohol flush |
Tolbutamide | 500–3000 mg | 6–12 hrs | Hypoglycaemia, hypersensitivity |
Tolazamide | 100–1000 mg | 12–24 hrs | Hypoglycaemia, hypersensitivity |
Aceohexamide | 500–1500 mg | 12–24 hrs | Hypoglycaemia, hypersensitivity |
Second Generation Sulfonylureas
Generic name | Dosage range per day | Duration of action | Side effects of class |
|---|---|---|---|
Glipizide | 2.5–40 mg | 12–24 hrs | Hypoglycaemia, hypersensitivity |
Glibenclamide | 5–20 mg | 12–24 hrs | Hypoglycaemia, hypersensitivity |
Glimeperide | 1.8 mg | 24 hrs | Hypoglycaemia, hypersensitivity |
Gliclazide | 40–240 mg | 12–24 hrs | Hypoglycaemia, hypersensitivity |
Agents Enhancing Effects of Insulin
Generic name | Dosage range per day | Duration of action | Side effects of class |
|---|---|---|---|
Metformin (Obimet) | 500–2500 mg | 6–8 hrs | Gl upset; diarrhoea; possible resumption of ovulation in premenopausal anovulatory patients; acidosis (if renal, liver, heart impairment present) |
Rosiglitazone | 4–8 mg | Very long | Renal and liver function studies should be done to monitor liver dysfunction, salt and water retention, edema, congestive heart failure |
Pioglitazone | 15–45 mg | Very long | Renal and liver function studies should be done to monitor liver dysfunction, salt and water retention, edema, congestive heart failure |
Other Oral Agents
Generic name | Dosage range per day | Duration of action | Side effects of class |
|---|---|---|---|
Repaglinide | 1.5–16 mg | 2–6 hrs | Hypoglycaemia, arthralgia, leukopenia |
Acarbose | 25–300 mg | < 4 hrs | Diarrhoea, abdominal discomfort, flatulence |
Miglitol | 25–300 mg | < 4 hrs | Diarrhoea, abdominal discomfort, use not recommended when significant renal dysfunction present |
Incidence of OHA Failure
Primary Failure
About one-third of Type 2 patients fail to respond to sulphonylurea treatment within one month of initiation of therapy.
Secondary Failure
- Of the patients that initially achieve satisfactory glycaemic control, about 5 to 10% go on to develop secondary failure each year, so that after 10 years only about half of the patients continue to have satisfactory response.
- From the data of the UKPD study, it appears by the sixth year, approximately 50% of the patients randomized to sulphonylurea needed supplemental insulin to maintain adequate glycaemic control.
Diagnosing OHA Failure
- It is a condition in which an individual does not respond adequately/satisfactorily with OHAs.
- Clinically, following parameters can be of great relevance in diagnosing OHA failure:
- Inadequate improvement in the classical signs and symptoms of diabetes viz., polydypsia, polyuria, polyphagia and fatigue.
- Inadequate/deteriorating blood glucose control. The objective to be pursued on this front is:Fasting blood glucose< 140 mg/100 mlPP blood glucose< 180 mg/100 ml
- High and increasing number of tablets with inadequate control; especially exceeding two to two and a half tablets in case of commonly used OHAs.
Dose at Which Review is Essential
Oral hypoglycaemic agent | mg per day | No of tablets |
|---|---|---|
Glibenclamide (Glyburide) | 10 | 2 |
Glipizide | 10 | 2 |
Gliclazide | 120 | 1.5 |
Poor performance with the above doses indicates the necessity to review the entire therapy and the therapeutic alternative to be considered at this point of time is initiation of insulin therapy.
In case of Type 2 diabetes, there are two possibilities:
- Stop OHA treatment and start insulin therapy (substitution) or
- Continue OHA treatment and add insulin therapy (supplement).
Oral antidiabetics are contraindicated in Type 1 diabetes and in Type 2 diabetes undergoing surgery, severe infections, liver and kidney disease, and gestational diabetes.14
INSULIN THERAPY
Type | Onset | Peak | Duration |
|---|---|---|---|
(1) Intermediate acting Lente | 2.5 hrs | 7–15 hrs | 24 hrs |
(2) Intermediate Acting NPH | 1.5 hrs | 4–12 hrs | 24 hrs |
(3) Pre-mixed (30/70 regular/NPH) | ½ hr | 2–8 hrs | 24 hrs |
(4) Pre-mixed 50/50 regular/NPH | ½ hr | 2–8 hrs | 24 hrs |
Indications
- OHA failure
- Pregnant diabetes
- Chronic infections in Type 2 diabetes, e.g. Tuberculosis
- Any other indications where a mixture of rapid and intermediate acting insulin is desired in the ratio of 30:70
- Premixed 50/50 regular NPH is indicated in patients with modern lifestyles on two large daily meals and those with high postprandial blood glucose levels
Amounts of Insulin
- Insulin regimen should be individualised depending on lifestyle, activity level and eating pattern.
- Continuous treatment and monitoring are the main stay.
- Efforts should be taken to keep blood glucose as close to the target range (72 mg/dl before a meal, 180 or less two hours after a meal).
Insulin Initiation
Substitution
- Stop OHA tablets.
- Start with intermediate insulin 0.2 units/kg body weight before breakfast or at bed-time (upto a maximum of 20 units)
- Increase by 2–6 units every 3–4 days if necessary.
Note: If postprandial blood glucose levels are too high add Rapid acting insulin. Alternatively, pre-mixed insulin could be used. If the dose exceeds 30–40 units, divide the dose into two daily. Injections 2/3rd before breakfast and 1/3rd before dinner.
Supplement
- Continue with OHA tablet without any change in dose.
- Increase dose by 2–4 units every 3–4 days if necessary.
- If more that 30–36 IU is required for adequate control (i.e FGB < 140 mg/100 ml), consider stopping OHA and continue on insulin.
Response to insulin treatment may be different in different patients and therefore some patients may require adjustment to the insulin regimen. The table given below depicts a simple way to adjust the dose.
Adjustment to Morning Injection
Before lunch | Before dinner | |
|---|---|---|
If persistent hyperglycaemia (or glycosuria) occur | Increase fast acting (soluble) insulin in the morning injection by 2 IU | Increase intermediate acting insulin in the morning injection by 2 IU |
If hypoglycaemia occurs without explanation | Decrease fast acting (soluble) insulin next morning by 2 IU | Decrease intermediate acting insulin next morning by 2 IU |
Adjustment to Evening Injection
Before lunch | Before dinner | |
|---|---|---|
If persistent hyperglycaemia (or glycosuria) occur | Increase fast acting (soluble) insulin in the evening injection by 2 IU | Increase intermediate acting insulin in the evening injection by 2 IU (after excluding nocturnal hypoglycaemia) |
If hypoglycaemia occurs without explanation | Decrease fast acting (soluble) insulin in the evening injection by 2 IU | Decrease intermediate acting insulin in the evening injection by 2 IU |
Diabetes mellitus is an endocrine disease involving faulty carbohydrate metabolism, probably of genetic origin.
Diabetes mellitus in association with pregnancy has become an increasingly common observation during the last decade due to three main reasons.
- More diabetic patients are achieving successful pregnancy outcome due to tight blood sugar control especially after the discovery of insulin.
- Carbohydrate intolerance is recognised as a common cause of fetal wastage and all patients presenting with bad obstetric history are investigated for abnormal glucose tolerance.
- The detection rate of diabetes in pregnancy has increased due to the awareness of the obstetrician, the setting up of special diabetic pregnancy centers and availability of better screening methods.
In order to understand diabetes in pregnancy it is important to review fuel metabolism in normal non-pregnant, non-diabetic pregnant and diabetic pregnant women.