Insulin treated Type 2 diabetes mellitus patients still have a considerably reduced life expectancy. The major causes of death are; cardiovascular complications (70%), renal failure (10%) and infections (6%) .The degree and duration of hyperglycemia being the most important factors. Presences of other risk factors of the diseases (dyslipidemia and hypertension) also play important roles in the development of the diseases.
They include:
Coronary artery disease (CAD): Diabetic patients have an increased risk of CAD due to increased rate of atherosclerosis and also presence of other risk factors that are common in diabetics than the general population such as smoking, hypertension and abnormal lipid levels. The American Diabetes Association recommends annual assessment of risks to identify diabetic patients who might benefit from interventions such as aspirin, ACE inhibitors and statin therapy.
Stroke: Occurs as a result of partial disruption of blood supply to the brain following narrowing of blood vessels (atherosclerosis) a process speeded up by hyperglycemia. Well controlled blood glucose levels and blood pressure help to reduce the risk of stroke in these patients.
Diabetic eye disease: Diabetes is the commonest cause of blindness among people of 20-74 years of age in the USA . Diabetic retinopathy (eye damage) involves new lesion development characterized by intra retinal micro vascular abnormalities such as increased vessel permeability, change in venous vessel caliber, altered retinal blood flow and consequently ischemia. This necessitates development of new vessels. The vessels mainly develop near the optic nerve and rupture easily leading to development of vitreous hemorrhages that cause fibrosis and detachment of the retina and ultimately vision loss.
Onset of cataracts is earlier in diabetics than the general population. High glucose levels lead to osmotic changes in the eye causing eyes to be more hypermetropic (long sightedness)
End stage renal disease (ESRD): Diabetes is the leading cause of ESRD in the USA. Damage is by three main mechanisms glomerular damage, ascending infections that are common in diabetic women and ischemia secondary to hypertrophy of afferent and efferent arterioles.
It can be prevented by screening of urine protein levels to detect microalbuminuria at an early stage which therapy can be instituted
Diabetic foot: Damage of the nerves leads to loss of sensation and renders the foot prone to injury. Foot ulceration is usually as a result of minimal trauma on a poorly perfused foot that has destroyed neuron function (neuropathic). Ulceration occurs after shedding of callous (tough) skin underneath which death of tissue occurred. Diabetic foot care involves retaining the viable tissue.
Joint contractures (in hands): They are seen in childhood diabetes. Metacarpophalangeal and interphalangeal joints of the hands cannot be opposed when Child’s hands are in prayer position. It occurs as a result of collagen glycosylation and it’s not progressive.
Diabetic neuropathy: Nerve damage occurs as a result of narrowing of small blood vessels that supply nerves thus deprive the nerves of oxygen and nourishment. This affects several nerves in the body to cause pain and tingling sensations in arms, toes and fingers if involving nerves of the extremities and also nausea and constipation if involving autonomic system nerves. The nerve damage to pudendal nerves coupled with risk factors such as anxiety, depression and excessive alcohol intake lead to development of erectile dysfunction in male diabetics.
Strict glucose monitoring is recommended to delay the onset of these diseases alongside measures to control associated risk factors such as strict blood pressure monitoring in hypertensive patients and dietary or lifestyle changes to control lipid levels.