Diabetes Flashcards
Diabetes Mellitus: Four Clinical Classes
Chronic, progressive metabolic disorder resulting from abnormalities in glucose, protein, and fat metabolism
- Type 1 diabetes: results from beta-cell destruction, leading to absolute insulin deficiency
- Type 2 diabetes: results from a progressive insulin secretory defect or insulin resistance
- Diabetes resulting from other causes (e.g., genetic defects in beta-cell function or insulin action; diseases of the exocrine pancreas, such as cystic fibrosis; and drug- chemical-induced)
- Gestational diabetes mellitus (GDM), which is diagnosed during pregnancy
Type 1 Diabetes: Patho and Treatment
Patho
- Autoimmune destruction of the pancreatic beta cells
- Genetically linked susceptibility
- Long preclinical period
- Absolute deficiency of insulin production by beta cells
Treatment
- insulin
Type 2 Diabetes: Patho
90% of cases are type 2 DM Patho - Genetics - Insulin resistance - Obesity - Insulin may be low, normal or high - Patients develop hyperlipidemia and HTN - We now understand the role of glucose absorption from gut associated with alteration of dipeptidyl peptidase 4 (DPP-4) and glucagon-like peptides (GLPs)
DM Complications
Macro- and Microvascular diseases of:
- eyes, kidneys, heart, peripheral vascular system, periodontal disease
Lipid metabolism
Platelet function
Neuropathy
- autonomic, peripheral
Screening for Type 2 DM
Patients 45 years of age or more with BMI greater than or equal to 25 should be tested. Those with values within normal limits should be tested every 3 years
Patients younger than 45 years of age with BMI greater than or equal to 25 who have additional risk factors should have more frequent testing
Additional risk factors are physical inactivity; having a first-degree relative with diabetes; member of high-risk ethnic group (African American, Hispanic, Native American, Asian American, Pacific Islander)
Additional risk factors are delivery of a baby weighing more than 9 lbs or previous diagnosis of GDM; HTN; HDL less than or equal to 250; PCOS; impaired glucose tolerance or impaired fasting glucose on previous testing; hx of CVD
DM Diagnostic Criteria
- Acute symptoms of diabetes plus casual plasma glucose concentration greater than or equal to 200
- Fasting plasma glucose greater than or equal to 126
- 2 hour post-load plasma glucose in an oral glucose tolerance test greater than or equal to 200. The test uses a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water
- HbA1c greater than or equal to 6.5%
Pre diabetes Diagnostic Criteria
- fasting plasma glucose 100-125 or
- plasma glucose 150-199 2 hours post-ingestion of standard glucose load (75 g) or
- A1c 5.7-6.4
Insulin: Pharmacodynamics
- Promotes protein synthesis by increasing amino acid transport into cells
- Stimulates glucose entry into cells as energy source
- Increases storage of glucose as glycogen (glycogenesis) in muscle and liver cells
- Inhibits glucose production in liver and muscle cells (glycogenolysis)
- Enhances fat storage (lipogenosis) and prevents mobilization of fat for energy (lipolysis and ketogenesis)
- Inhibits glucose formation from noncarbohydrate sources, such as amino acids (glucogenesis)
Selecting Oral Antidiabetic Agents: insufficient production of endogenous insulin
Sulfonylureas cause an increase in insulin production
Meglitinides, insulin secretagogues, increase secretion of insulin from beta cell
DPP-4 Inhibitors act on the incretin hormone system to indirectly increase insulin production
Selecting Oral Antidiabetic Agents: Tissue insensitivity to Insulin
Thiazolidinediones (TZDs) improve insulin sensitivity Selecting Oral Antidiabetic Agents:
Selecting Oral Antidiabetic Agents: Tissue insensitivity to Insulin
Thiazolidinediones (TZDs) improve insulin sensitivity
Selecting Oral Antidiabetic Agents: Impaired response of beta cells
Meglitinides increase secretion of insulin
Oral Agents: Excessive production of glucose by liver
Metformin improves hepatic response to elevated BG and decreases glucose production, and decreases GI absorption
Alpha-glucosidase inhibits inhibit absorption of cholesterol (CHO) in GI system
Goals of Treatment
- Near normalization of BG
- – Individualized goals for children, pregnant women, and older adults
- Prevention of acute complications
- Prevention of chronic complications
- Appropriate individualized self-management
Diabetes: Treatment Targets
- Glycemic Control:
- – HbA1c less than 7% (unless >65 years)
- – Preprandial plasma glucose 70 to 130 mg/dL
- – 2 hour post prandial plasma glucose less than 180
- BP less than 130/80 (if tolerated, and no frail older adult)
- Lipids
- – LDL less than 100 mg/dL
- – triglycerides less than 150 mg/dL
- – HDL greater than 50 mg/dL
- Random urine albumin/creatinine less than 30 mcg/mg creatinine
