Diabetes mellitus is a chronic metabolic disorder marked by persistent hyperglycemia. This state arises from defects in insulin secretion, insulin action, or both. Insulin is a vital hormone produced by the beta cells of the islets of Langerhans in the pancreas. It facilitates the uptake of glucose from the bloodstream into body cells for energy.
When this system fails, glucose accumulates in the blood, leading to widespread systemic effects. Over time, high blood sugar damages blood vessels and nerves, disrupting the normal functioning of multiple organ systems including the cardiovascular system, kidneys, eyes, and peripheral nerves. The global prevalence of diabetes continues to rise, making it a major public health concern in Nigeria and worldwide.
Diabetes mellitus is broadly categorized into several distinct clinical types based on the underlying etiology:
Without sufficient insulin, glucose cannot enter peripheral cells, leaving tissues energy-starved despite abundant circulating sugar. The body interprets this cellular starvation as fasting, triggering compensatory mechanisms that worsen hyperglycemia.
The liver responds by breaking down stored glycogen into glucose through glycogenolysis and creating new glucose via gluconeogenesis. Concurrently, the lack of insulin encourages the breakdown of stored fats for energy. This lipolysis releases free fatty acids into the bloodstream, which the liver converts into ketones. Accumulation of these acidic ketone bodies leads to metabolic acidosis, a dangerous condition seen frequently in Type 1 diabetes.
The classic clinical presentation of uncontrolled diabetes is defined by the three 'Ps':
Other common assessment findings include unexplained weight loss, fatigue, blurred vision from osmotic swelling of the eye lens, and slow-healing skin infections or wounds.
Diagnosis relies on objective blood test measurements confirming chronic hyperglycemia. A random blood glucose reading of 11.1 mmol/L or higher, combined with classic symptoms, confirms diabetes. Fasting plasma glucose of 7.0 mmol/L or higher on two separate occasions is also diagnostic.
The Glycated Hemoglobin (HbA1c) test measures average blood glucose over the preceding two to three months by assessing glucose attached to hemoglobin in red blood cells. An HbA1c level of 6.5% or higher indicates diabetes. Additionally, an oral glucose tolerance test may be used, particularly in pregnant women, to assess how the body processes a standardized glucose load.
Management aims to maintain blood glucose levels as close to normal as possible to prevent complications. Treatment always involves medical nutrition therapy, regular physical exercise, and patient education.
Pharmacological interventions vary by type. Patients with Type 1 diabetes require daily insulin therapy. Oral anti-diabetic agents, such as metformin, are the first-line pharmacotherapy for Type 2 diabetes. Metformin works by reducing hepatic glucose production and improving insulin sensitivity in peripheral tissues. Other oral agents stimulate insulin secretion or delay carbohydrate digestion in the gut. If oral medications fail to control Type 2 diabetes over time, injectable therapies or insulin may be added.
Diabetes gives rise to severe acute and chronic complications if poorly managed. Acute emergencies include Diabetic Ketoacidosis (DKA), characterized by severe hyperglycemia, ketosis, and metabolic acidosis, and Hyperosmolar Hyperglycemic State (HHS), marked by extreme blood glucose and dehydration without significant ketoacidosis.
Chronic complications stem from vascular damage and are split into two categories:
Nurses play a critical role in managing diabetes through comprehensive care planning and client education. Key nursing interventions include monitoring blood glucose levels, assessing skin integrity, and evaluating renal function.
Education must focus on self-monitoring of blood glucose, proper injection techniques for insulin, meal planning, and recognizing signs of hypoglycemia and hyperglycemia. Foot care is paramount: nurses must teach clients to inspect their feet daily, wear properly fitting shoes, and avoid walking barefoot to prevent ulcers and subsequent amputations.