Unit 4 Metabolic Disorders: Diabetes Mellitus

Comprehensive vocabulary flashcards covering the pathophysiology, clinical types, diagnostic criteria, therapeutic interventions, medications, acute glycemic complications, and long-term consequences of diabetes mellitus.

Diabetes Mellitus

A metabolic disorder characterized by glucose intolerance resulting from faulty insulin production or tissue insensitivity to insulin, leading to altered carbohydrate, fat, and protein metabolism as well as long-term complications.

Type 1 Diabetes

A form of diabetes (formerly called insulin-dependent diabetes mellitus [IDDM] or juvenile diabetes) accounting for $5\%$ of cases, caused by an autoimmune destruction of beta cells (often triggered by a virus) that results in zero insulin secretion; primarily affects young, lean individuals and is prone to ketosis.

Type 2 Diabetes

A form of diabetes (formerly called non–insulin-dependent diabetes mellitus [NIDDM] or adult onset) accounting for $95\%$ of cases, characterized by reduced beta cell numbers and decreased tissue sensitivity to insulin; strongly linked to heredity ($90\%$) and obesity, and typically not ketosis-prone.

The 3 P's

The classic triad of symptoms indicating diabetes mellitus: polydipsia (excessive thirst), polyuria (excessive urination), and polyphagia (excessive hunger).

Fasting Blood Glucose Test Diagnostic Threshold

A plasma glucose value equal to or greater than $126\,\text{mg/dL}$ ($\ge 126\,\text{mg/dL}$) used to diagnose diabetes mellitus.

Random Blood Glucose Test Diagnostic Threshold

A blood glucose level equal to or greater than $200\,\text{mg/dL}$ ($\ge 200\,\text{mg/dL}$) used as a diagnostic criterion for diabetes mellitus.

Oral Glucose Tolerance Test (OGTT) Diagnostic Threshold

A blood glucose level exceeding $200\,\text{mg/dL}$ ($> 200\,\text{mg/dL}$) measured $2\,\text{hours}$ following glucose ingestion.

Hemoglobin A1c ($\text{HbA}_{1c}$) Diagnostic Threshold

A glycated hemoglobin measurement greater than $6.5\%$ ($> 6.5\%$) indicative of diabetes mellitus.

Very Short-Acting Insulin

Rapid-acting insulins including Lispro (Humalog), Aspart (NovoLog), Glulisine (Apidra), and Inhaled Insulin (Afreeza), characterized by an onset of $5\text{ to }20\,\text{minutes}$, peak of $30\text{ to }90\,\text{minutes}$, duration of $2\text{ to }5\,\text{hours}$, administered no more than $15\,\text{minutes}$ before meals.

Short-Acting Insulin

Insulin Regular (Humulin R, Novolin R) with an onset of $30\,\text{minutes}$, peak of $2\text{ to }5\,\text{hours}$, and duration of $5\text{ to }8\,\text{hours}$, administered not more than $30\,\text{minutes}$ before meals.

Intermediate-Acting Insulin

Neutral protamine Hagedorn (NPH) (Humulin N, Novolin N) with an onset of $1\text{ to }2\,\text{hours}$, peak of $6\text{ to }12\,\text{hours}$, and duration of $18\text{ to }26\,\text{hours}$, given not more than $30\,\text{minutes}$ before a meal.

Basal Insulin

Long-acting insulins such as glargine (Lantus AE) and detemir (Levemir), having an onset of $1\text{ to }2\,\text{hours}$, no peak, and duration up to $24\,\text{hours}$, administered at the same time each day.

Insulin Injection Site Rotation

The practice of rotating subcutaneous injection locations among mapped areas of the arms, abdomen, thighs, and buttocks to prevent lipodystrophy and promote consistent insulin absorption.

Oral Hypoglycemics

Non-insulin medications for type 2 diabetes that function by stimulating the pancreas to release insulin, increasing tissue sensitivity to insulin, slowing carbohydrate digestion and absorption, or reducing renal glucose reabsorption.

Pramlintide (Symlin)

A non-insulin injectable agent classified as an amylin analog, used for patients with type 1 diabetes.

Incretin Mimetics

Non-insulin injectable agents used in type 2 diabetes management, including exenatide (Byetta, Bydureon) and liraglutide (Victoza).

Hyperglycemia

An abnormally elevated blood glucose level ($> 126\,\text{mg/dL}$) caused by overeating, stress, illness, or insufficient medication, presenting with the 3 P's, blurred vision, fatigue, headache, abdominal pain, ketonuria, or coma.

Hypoglycemia

A state where blood glucose drops below $70\,\text{mg/dL}$ ($< 70\,\text{mg/dL}$), often caused by excess insulin, exercise, or insufficient food, presenting with autonomic fight-or-flight symptoms (shakiness, diaphoresis, palpitations) and neuroglycopenic signs.

Neuroglycopenia

A shortage of glucose delivery to the brain resulting from hypoglycemia, characterized by irritability, confusion, headache, dizziness, seizures, and coma.

Rule of 15 (Hypoglycemia Treatment)

The protocol of administering $15\text{ to }20\,\text{g}$ of fast-acting carbohydrates for low blood glucose, rechecking blood glucose in $15\,\text{minutes}$, repeating if necessary, and providing a snack if the next meal is over $1\,\text{hour}$ away.

Diabetic Ketoacidosis (DKA)

An acute life-threatening emergency primarily seen in type 1 diabetes resulting from severe insulin deficiency, where starvation of cells triggers fat breakdown into acidic ketones, leading to metabolic acidosis, dehydration, and electrolyte derangements.

Kussmaul Respirations

Deep, rapid breathing pattern observed in patients experiencing diabetic ketoacidosis, functioning as a respiratory compensatory mechanism to blow off excess carbon dioxide and lessen acidosis.

Macrovascular Complications

Chronic cardiovascular complications of diabetes caused by damage to large vessels, consisting of stroke, heart attack (myocardial infarction), and peripheral vascular disease.

Microvascular Complications

Chronic diabetic complications caused by damage to small blood vessels and capillary beds, including retinopathy, nephropathy, and neuropathy.

Diabetic Foot Ulcer

A chronic open wound or tissue necrosis on the lower extremity caused by a combination of diabetic neuropathy, peripheral vascular disease, and impaired infection resistance.