Diabetes Mellitus is a metabolic disorder wherein the pancreas does not secrete enough insulin in order for glucose to enter the cell. Normally, the glucose is converted to energy which is needed for everyday requirements. In diabetes, glucose cannot enter the cell because of insufficient insulin and accumulates in the blood resulting to a condition known as hyperglycemia. The increase in blood sugar then results to a decrease in high density lipoprotein (HDL) level, and increase in triglyceride and low density lipoprotein (LDL).
This condition is known as diabetic dyslipidemia. Diabetic dyslipidemia increases a person’s risk for heart disease due to low amounts of HDL which prevents LDL from accumulating in the arteries, high amounts of triglycerides which leads to HDL depletion and increased amounts of the smaller denser LDL and formation of the smaller, denser LDL that increases the amount of plaque in the arteries (Oguejiofo, 2010). As the disease progresses, the plaques build up resulting to a decrease in the diameter of the vessel.
These plaques may become unstable and ruptured resulting to damage in the internal wall of the vessels. Consequently, it triggers thrombus formation which further narrows the diameter of the blood vessel. The narrowing of blood vessel depletes the supply of blood as well as oxygen and nutrients to the part succeeding it thereby making it ischemic. It may result to potentially life threatening complications like myocardial ischemia and infarction. Naturally, the heart is supplied by blood and oxygen through the coronary artery.
The deposition of atherosclerotic plaques and thrombus formation in this artery result to depletion of blood to some parts of the heart making it ischemic, which may trigger an ischemic cascade. Myocardial cells will die and will not grow again. Instead, they are replaced by scar tissues which have lesser conducting and stretching ability compared to myocardial cells. This results to infarction of the heart or heart attack. The danger with the thrombus formation is the dislodgement of the thrombi resulting to emboli.
Emboli from the heart are distributed evenly throughout the body according to cardiac output, but more than 80% of symptomatic or clinically recognized emboli involve the brain. Of emboli to the brain, approximately 80% involve the anterior circulation (i. e. , carotid artery territory) while 20% involve the vertebrobasilar adistribution, proportional to the distribution of cerebral blood flow (Schneck, 2008). Once embolus reaches the brain, it can block the important arteries supplying it which can also result to ischemia of the neurons. This will result to brain attack or stroke.
The ischemia causes the cells to lose its ability to conduct impulses which can result to impaired bodily functions. Diabetes retinopathy is also a major complication of diabetes. High blood glucose impairs the ability of retinal vessels to constrict and precisely regulate blood flow. It may injure the interior of the blood vessels which results to the destruction of the capillaries and inadequate blood circulation to the retinal blood vessels (Chous, 2006). In an attempt to nourish the eyes with enough blood, neovascularization occurs wherein abnormal, fragile blood vessels are formed.
This is referred to as proliferative diabetic retinopathy. The fragile blood vessels may leak blood to the vitreous humor resulting to clouding of vision, and blindness if unattended. According to American Optometric Association (2006), diabetes with prolonged periods of high blood sugar can lead to accumulation of fluid in the lens inside the eye that controls eye focusing. Vessels in the retina have pericytes which are responsible for keeping together the endothelial cells in the blood vessels and preventing leakage of fluid.
In patients with diabetes, connections within the retina weaken. The increase in triglyceride levels in the blood strips off the pericytes found in the retinal blood vessels, causing outpouchings or microaneurysms. The aneurysm results to leakage of the fluids and proteins to the macula, the yellow portion of retina, causing it to swell and thicken. Macula holds the cones which is responsible for central vision, color, and form. Any form of abnormalities on this yellow part of the retina may result to distorted vision and leaving it untreated may cause blindness.