Diabetes mellitus type 2 is a disorder that is characterized by high blood glucose (sugar) in the context of insulin resistance and relative insulin deficiency. Initially managed by increasing exercise and dietary life style modification, medications are typically needed as the disease progresses.

 

Causes

The major risk factors for type II diabetes

• Age - More than 45 years (although, type 2 diabetes mellitus is occurring with increasing frequency in young individuals)
• Obesity - (approximately 90% of patients with type 2 diabetes mellitus)
• Family history of type 2 diabetes (eg, parent or sibling)
• History of previous impaired glucose tolerance or impaired fasting glucose
• Hypertension
• Dyslipidemia ( [HDL] cholesterol level <40 mg/dL or triglyceride level >150 mg/dL)
• History of gestational diabetes mellitus or of delivering a baby with a birth weight of >4 kgs
• Polycystic ovarian syndrome (PCOD)

Other contributing factors (Secondary diabetes)

• Cushing’s disease
• Acromegaly
• Pheochromacytoma
• Syndrome X
• Hemochromatosis
• Pancreatic insufficiency
• Over use of steroids
• Following trauma or surgery

MODY

• Maturity-onset diabetes of the young (MODY) is a form of type 2 diabetes mellitus that affects many generations in the same family with an onset in  younger individuals less than 25 years.
• MODY is associated with autosomal dominant inheritance pattern.
• It’s characterized by absence of auto antibodies, correction of fasting hyperglycemia without insulin for at least 2 years, and absence of ketosis.
• Variants in 2 of the genes associated with MODY (HNF-1alpha and, to a lesser extent, HNF-4alpha) have been shown to predict future type 2 diabetes.

Pre- diabetes

• Pre-diabetes usually precedes overt type 2 diabetes.
• Pre-diabetes is defined by a fasting blood glucose level of 100-125 mg/dL or a 2-hour post oral glucose tolerance test (OGTT) glucose level of 140-200 mg/dL.
• Patients who have pre-diabetes have an increased risk for macrovascular complications of diabetes mellitus as well as diabetes.

Metabolic syndrome

Also called as Syndrome X or Reavan's syndrome

• Metabolic syndrome is due to insulin resistance, can occur in patients with overtly normal glucose tolerance, pre-diabetes, or diabetes.
• An elevated fasting blood glucose (>125) level is the first indication of insulin resistance.
• But fasting insulin levels are generally increased long before the fasting blood sugars increase.

Clinical features

Most patients with type 2 diabetes mellitus are asymptomatic for years.

• Excessive urine production- polyuria
• Increased fluid intake-polyuria
• Increased food intake- polyphagia
• Nocturia
• Blurred vision
• Unexplained weight loss
• Lethargy
• Fatigue
• Erectile dysfunction
• Lower extremity paresthesias- pins and needle sensation

Physical findings in type II diabetes

• Central obesity
• Eye hemorrhages or exudates
• Acanthosis nigricans
• Dry feet, ulcers, muscle atrophy, and claw toes
• Neurologic signs- decreased or absent light touch, vibration sense, temperature sensation.

Complications

• Microvascular complications- retinopathy (deterioration in vision), nephropathy (kidney disease)
• Macrovascular complications- hypertension, Coronary heart disease, cerbrovascular disease (stroke), peripheral vascular disease, hyerlipidemia
• Diabetic foot
• Diabetic neuropathy
• Frequent infections
• Balanitis- inflammation of glans penis, mainly by fungus
• Hypoglycemic unawareness
• Hyperosmolar hyperglycemic nonketotic coma

Diagnosis

Diagnosis of type II diabetes mellitus

• Classical symptoms of diabetes mellitus (polyuria, polyphagia, polydypsia, and weight loss and random plasma blood glucose of >200 mg/dl)
• Fasting plasma glucose of >125 mg/dl
• Two hour post glucose load (75g), plasma glucose levels 200 mg/dl, and confirmed by repeat test

Tests

• Blood glucose testing- fasting blood sugar (FBS), post prandial blood sugar (PPBS)
• Glucose tolerance test (GTT)
• Urine for reducing sugars (glucose) and ketone bodies
• Urine microalbumunuria (30-300 mg/d)
• Fasting C-peptide levels >1 ng/dl for more than 1-2 yrs is suggestive of type II diabetes
• Hemoglobin A1c (HbA1c or A1c), or glycosylated hemoglobin- normal levels are 6-7 %.
• HbA1c measurements are for monitoring long-term glycemic control and reflect glycemia for the previous 3 months.
• HbA1c currently used to guide management decisions

Treatment

Dietary management

• More of carbohydrate must be given as complex starches rather than simple sugars as they breakdown more slowly to release glucose in blood.
• The presence of fiber in complex carbohydrate like grains, vegetables and other starches slows the glucose absorption.
• One should emphasize more on the high fiber food instead of high fiber supplements.
• Foods to avoid- Glucose, sugar, honey, all sweets, chocolates and candies
• Foods to be restricted- alcoholic beverages, fried food, deep fried food, dry fruits, potatoes, sweet potatoes
• Foods to be taken- Green, leafy vegetables, tomatoes, cucumber. Fruits like guava, amla, papaya, and others
• It is important to control the amount and time of food intake. Meals should not be missed.
• Try to substitute the craving for sweet by taking some fruit

Exercise

• Exercises in diabetics help to control their bodies, gain strength, courage and confidence.
• Exercises improves circulation mainly arms and legs preventing diabetic complications like neuropathy, diabetic foot.
• It also reduces the risk of heart diseases, stroke found in diabetics.

Aerobic exercises like walking, jogging, aerobic dance or bicycling. If there are problems in feet or legs, you may consider exercises like swimming, bicycling, rowing or chair exercises.

The best among aerobic exercise is brisk walking, but need to regularly for 4-5 days in a week for at least 25- 30 min.

Aerobic tap backs: Start with the feet together. Tap the right foot to the back and return to center, tap the left foot back and return to the center. Alternate tapping the right and left foot back as you press the both arms to the front.

Antidiabetic medications

Antidiabetic drug	examples	Advantages	Adverse effects
Insulin secretogouges- Sulfonylureas	Glipizide, Gliclazide, Glibenclamide, Glibornuride and Glimepiride	Stimulates insulin secretion by beta cells of the pancreas	Hypoglycemia, nausea, vomiting, antabuse effects, hyponatremia and others
Insulin secretogouges- Meglitinides	Repaglinide, Nateglinide	Stimulates insulin release from pancreatic beta cells.	Hypoglycemia is faster and shorter compared to sulfonylureas
Insulin enhancers- Thiozolidinediones	Pioglitozone, Rosiglitazone	Decrease of hyperglycemia, glycosylated hemoglobin, plasma free fatty acids.	Weight gain, fluid retention, heart failure, and liver distrurbances
Alpha-glucosidase inhibitors	Acarbose,Miglitol	Decreases post-prandial hyperglycemia.	Abdominal flatulence, bloating, diarrhea and pain.
Aldose reductase inhibitors	Tolrestat, Imerestat, Vitamin-C 100mg/day	Reduces sorbitol accumulation in RBC’s
Insulin enhancers- Biguanides	Metformin	Decreases hyperglycemia without risk of hypoglycemia. Suppresses appetite- useful in obese individuals	Lactic acidosis, nausea, vomiting and diarrhea.

 

 

Newer class of drugs

Testosterone treatment is very efficient in insulin resistance.

Peptide analogues

• Glucagon like peptide analogues- Exenatide
• Dipeptidyl pepditase-4 inhibitors- Sitagliptin
• Amylin analogue- Pramlintide

Insulin preparations

The primary indication of insulin is in type I diabetes mellitus and gestational diabetes.

If Antidiabetic medications fail, insulin therapy may be necessary – usually in addition to oral medication therapy – to maintain normal or near normal glucose levels.