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Diabetes Mellitus Nursing Study Guide
For NCLEX & Med-Surg Revision 2026/2027
How to Use This Guide
• Prioritize Safety: For NCLEX, always think: "What is the
priority?" (Airway, Breathing, Circulation - ABCs, then safety,
then comfort).
• Connect the Concepts: Diabetes affects every body system. Link
the pathophysiology to the complications.
• Know Your Numbers: Memorize the critical lab values and blood
glucose parameters.
1. Foundational Concepts & Pathophysiology
What is Diabetes?
A chronic metabolic disorder characterized by hyperglycemia resulting
from defects in insulin secretion, insulin action, or both.
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Type 1 Diabetes Mellitus Type 2 Diabetes Mellitus
Feature
(T1DM) (T2DM)
Insulin Resistance (cells don't
Autoimmune
respond to insulin) followed
Pathophysiology destruction of pancreatic
by decreased insulin
beta cells.
production.
Gradual, typically in adults (bu
Sudden, typically in
Onset increasing in youth due to
childhood/adolescence.
obesity).
Usually thin or normal
Body Habitus Often overweight or obese.
weight.
Absent (must take insulin to Present, but insufficient or
Insulin Presence
live). poorly utilized.
Lifestyle modification, oral
Treatment Insulin (only option). antihyperglycemics, non-insuli
injectables, and/or insulin.
Rarely develop DKA; prone to
Prone to Diabetic
Ketosis Hyperosmolar Hyperglycemic
Ketoacidosis (DKA).
State (HHS).
Key Hormones:
• Insulin: Lowers blood glucose (BG). Promotes glucose uptake by
cells, glycogenesis (storing glucose as glycogen in liver/muscle).
• Glucagon: Raises blood glucose. Promotes glycogenolysis
(breaking down glycogen) and gluconeogenesis (making new
glucose).
Diabetes Mellitus Nursing Study Guide
For NCLEX & Med-Surg Revision 2026/2027
How to Use This Guide
• Prioritize Safety: For NCLEX, always think: "What is the
priority?" (Airway, Breathing, Circulation - ABCs, then safety,
then comfort).
• Connect the Concepts: Diabetes affects every body system. Link
the pathophysiology to the complications.
• Know Your Numbers: Memorize the critical lab values and blood
glucose parameters.
1. Foundational Concepts & Pathophysiology
What is Diabetes?
A chronic metabolic disorder characterized by hyperglycemia resulting
from defects in insulin secretion, insulin action, or both.
, 2|Page
Type 1 Diabetes Mellitus Type 2 Diabetes Mellitus
Feature
(T1DM) (T2DM)
Insulin Resistance (cells don't
Autoimmune
respond to insulin) followed
Pathophysiology destruction of pancreatic
by decreased insulin
beta cells.
production.
Gradual, typically in adults (bu
Sudden, typically in
Onset increasing in youth due to
childhood/adolescence.
obesity).
Usually thin or normal
Body Habitus Often overweight or obese.
weight.
Absent (must take insulin to Present, but insufficient or
Insulin Presence
live). poorly utilized.
Lifestyle modification, oral
Treatment Insulin (only option). antihyperglycemics, non-insuli
injectables, and/or insulin.
Rarely develop DKA; prone to
Prone to Diabetic
Ketosis Hyperosmolar Hyperglycemic
Ketoacidosis (DKA).
State (HHS).
Key Hormones:
• Insulin: Lowers blood glucose (BG). Promotes glucose uptake by
cells, glycogenesis (storing glucose as glycogen in liver/muscle).
• Glucagon: Raises blood glucose. Promotes glycogenolysis
(breaking down glycogen) and gluconeogenesis (making new
glucose).
