DM

Question 1

What is the primary mechanism leading to type 1 diabetes mellitus (DM)?
A. Insulin resistance in peripheral tissues
B. Autoimmune destruction of insulin-producing beta cells
C. Increased hepatic glucose production
D. Genetic mutations causing insulin receptor defects

Answer 1

Correct Answer: B. Autoimmune destruction of insulin-producing beta cells
Rationale: Type 1 DM develops due to autoimmunity targeting the beta cells of the pancreas, leading to insulin deficiency and hyperglycemia.

Question 2

Which characteristic is most strongly associated with type 2 diabetes mellitus (DM)?
A. Early onset of hyperglycemia (usually <25 years)
B. Variable degrees of insulin resistance and impaired insulin secretion
C. Exclusively autoimmune beta-cell destruction
D. Rapid onset and complete insulin dependence

Answer 2

Correct Answer: B. Variable degrees of insulin resistance and impaired insulin secretion
Rationale: Type 2 DM is a heterogeneous disorder involving a combination of insulin resistance, reduced insulin secretion, and increased hepatic glucose production.

Question 3

What is a defining feature of maturity-onset diabetes of the young (MODY)?
A. Autoimmune beta-cell destruction
B. Autosomal recessive inheritance
C. Early onset of hyperglycemia and impaired insulin secretion
D. Predominant insulin resistance

Answer 3

Correct Answer: C. Early onset of hyperglycemia and impaired insulin secretion
Rationale: MODY is a monogenic form of diabetes with autosomal dominant inheritance, early-onset hyperglycemia (typically <25 years), and impaired insulin secretion without significant insulin resistance.

Question 4

What is a distinguishing feature of fulminant diabetes, noted primarily in Japan?
A. Gradual development of hyperglycemia and insulin resistance
B. Autosomal dominant inheritance and early onset
C. Acute onset, possibly linked to viral infection of the islets
D. Strong association with obesity and metabolic syndrome

Answer 4

Correct Answer: C. Acute onset, possibly linked to viral infection of the islets
Rationale: Fulminant diabetes is a rare form of type 1 diabetes characterized by sudden onset, primarily reported in Japan, and is potentially associated with viral infections affecting pancreatic islets.

Question 5

What is the genetic inheritance pattern of monogenic diabetes such as MODY?
A. Autosomal dominant
B. Autosomal recessive
C. X-linked recessive
D. Mitochondrial

Answer 5

Correct Answer: A. Autosomal dominant
Rationale: Monogenic diabetes, including MODY, follows an autosomal dominant inheritance pattern, often presenting with an early onset of hyperglycemia.

Question 6

What is the diagnostic fasting plasma glucose (FPG) threshold for diabetes mellitus (DM)?
A. ≥5.6 mmol/L (100 mg/dL)
B. ≥6.1 mmol/L (110 mg/dL)
C. ≥7.0 mmol/L (126 mg/dL)
D. ≥11.1 mmol/L (200 mg/dL)

Answer 6

Correct Answer: C. ≥7.0 mmol/L (126 mg/dL)
Rationale: The diagnostic threshold for diabetes mellitus is an FPG of ≥7.0 mmol/L (126 mg/dL), reflecting impaired glucose regulation and hyperglycemia consistent with diabetes.

Question 7

What is the range of 2-hour plasma glucose (2-h PG) values for prediabetes during an oral glucose tolerance test?
A. 5.6–6.9 mmol/L (100–125 mg/dL)
B. 7.8–11.0 mmol/L (140–199 mg/dL)
C. ≥11.1 mmol/L (200 mg/dL)
D. ≤5.5 mmol/L (99 mg/dL)

Answer 7

Correct Answer: B. 7.8–11.0 mmol/L (140–199 mg/dL)
Rationale: Prediabetes is characterized by a 2-h PG of 7.8–11.0 mmol/L (140–199 mg/dL) following a 75-gram oral glucose challenge.

Question 8

What hemoglobin A1c (HbA1c) value is diagnostic for diabetes mellitus?
A. ≥5.6%
B. ≥6.0%
C. ≥6.5%
D. ≥7.0%

Answer 8

Correct Answer: C. ≥6.5%
Rationale: An HbA1c of ≥6.5% is one of the diagnostic criteria for diabetes mellitus and reflects chronic hyperglycemia over approximately 3 months.

Question 9

Which of the following random blood glucose values is diagnostic for diabetes mellitus in the presence of symptoms?
A. ≥5.6 mmol/L (100 mg/dL)
B. ≥7.0 mmol/L (126 mg/dL)
C. ≥11.1 mmol/L (200 mg/dL)
D. ≥14.0 mmol/L (250 mg/dL)

Answer 9

Correct Answer: C. ≥11.1 mmol/L (200 mg/dL)
Rationale: A random blood glucose of ≥11.1 mmol/L (200 mg/dL) in a patient with classic symptoms of hyperglycemia or hyperglycemic crisis confirms the diagnosis of diabetes.

Question 10

How is glucose intolerance first identified during the second or third trimester of pregnancy classified?
A. Type 1 diabetes mellitus
B. Type 2 diabetes mellitus
C. Gestational diabetes mellitus (GDM)
D. Pregestational diabetes mellitus

Answer 10

Correct Answer: C. Gestational diabetes mellitus (GDM)
Rationale: Glucose intolerance that develops during the second or third trimester of pregnancy is classified as GDM, reflecting insulin resistance due to the metabolic changes of pregnancy.

Question 11

What does the American Diabetes Association (ADA) recommend for diabetes diagnosed during the first trimester of pregnancy?
A. It should be classified as GDM.
B. It should be classified as preexisting pregestational diabetes.
C. It should be monitored without classification.
D. It should be treated as type 1 diabetes mellitus.

Answer 11

Correct Answer: B. It should be classified as preexisting pregestational diabetes.
Rationale: According to the ADA, diabetes diagnosed within the first trimester is likely preexisting and should be classified as pregestational diabetes rather than GDM.

Question 12

What is the recommended frequency for diabetes or prediabetes screening in women with a history of GDM?
A. Annually
B. Every 2 years
C. At least every 3 years
D. Every 5 years

Answer 12

Correct Answer: C. At least every 3 years
Rationale: The ADA recommends lifelong screening for diabetes or prediabetes in women with a history of GDM, at least every 3 years.

Question 13

For individuals with a history of GDM, how often should diabetes screening occur?
A. Annually
B. Every 2 years
C. Every 3 years
D. Every 5 years

Answer 13

Correct Answer: C. Every 3 years
Rationale: Women with a history of GDM should undergo diabetes screening at least every 3 years, as recommended by the ADA.

Question 14

At what age should initial diabetes screening begin for individuals without additional risk factors?
A. 35 years
B. 40 years
C. 45 years
D. 50 years

Answer 14

Correct Answer: C. 45 years
Rationale: The ADA recommends that individuals without risk factors begin diabetes screening at age 45 and repeat testing every 3 years if results are normal.

Question 15

What is the precursor molecule for insulin synthesis?
A. Proinsulin
B. Preproinsulin
C. Insulin-like growth factor I
D. C-peptide

Answer 15

Correct Answer: B. Preproinsulin
Rationale: Insulin is initially synthesized as preproinsulin, a single-chain 86-amino-acid precursor polypeptide, which undergoes further processing to form proinsulin and then mature insulin.

Question 16

What is the clinical significance of measuring C-peptide levels?
A. It serves as an indicator of beta-cell dysfunction.
B. It allows discrimination between endogenous and exogenous insulin sources.
C. It is used to detect insulin resistance.
D. It provides insight into amyloid deposition in type 2 diabetes.

Answer 16

Correct Answer: B. It allows discrimination between endogenous and exogenous insulin sources.
Rationale: C-peptide is co-secreted with insulin and is cleared more slowly, making it a useful marker to differentiate between endogenous and exogenous insulin in cases of hypoglycemia.

Question 17

According to the ADA, which group of individuals should be considered for metformin to reduce the risk of progression to diabetes?
A. Individuals with type 1 diabetes
B. Individuals with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) at very high risk
C. Individuals with type 2 diabetes
D. Individuals with a history of gestational diabetes, regardless of risk factors

Answer 17

Correct Answer: B. Individuals with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) at very high risk
Rationale: The ADA recommends metformin for individuals with IFG and IGT who are at very high risk, such as those under 60 years of age, with a BMI ≥35 kg/m², or a history of gestational diabetes mellitus (GDM).

Question 18

Which gene mutation is associated with MODY 3?
A. HNF-4α
B. HNF-1α
C. HNF-1β
D. Glucokinase

Answer 18

Correct Answer: B. HNF-1α
Rationale: MODY 3 is caused by mutations in the HNF-1α gene, which affects islet development and insulin secretion.

Question 19

What is a major clinical implication of identifying an HNF-1α mutation (MODY 3)?
A. Patients are resistant to sulfonylureas and require insulin therapy.
B. Patients often require glucokinase inhibitors for stable glycemic control.
C. Patients may respond to sulfonylureas, allowing discontinuation of insulin therapy.
D. Patients experience stable mild hyperglycemia without the need for treatment.

Answer 19

Correct Answer:
C. Patients may respond to sulfonylureas, allowing discontinuation of insulin therapy.

Rationale:
Patients with an HNF-1α mutation (MODY 3) can experience a progressive decline in glycemic control but often respond well to sulfonylureas. This responsiveness can lead to the discontinuation of insulin, which is a significant clinical implication as it differentiates MODY 3 from type 1 diabetes.

Question 20

What is a characteristic feature of MODY 2?
A. Progressive decline in glycemic control requiring insulin
B. Stable mild-to-moderate hyperglycemia not requiring treatment
C. Renal cysts and abnormal liver function tests
D. Pancreatic agenesis

Answer 20

Correct Answer: B. Stable mild-to-moderate hyperglycemia not requiring treatment
Rationale: MODY 2 results from glucokinase mutations, which lead to mild, stable hyperglycemia without the need for treatment.

Question 21

Which clinical feature is most commonly associated with mutations in HNF-1β (MODY 5)?
A. Progressive decline in glycemic control responsive to sulfonylureas
B. Progressive impairment of insulin secretion, renal cysts, and abnormal liver function
C. Stable hyperglycemia not requiring treatment
D. Pancreatic agenesis

Answer 21

Correct Answer: B. Progressive impairment of insulin secretion, renal cysts, and abnormal liver function
Rationale: HNF-1β mutations (MODY 5) are associated with progressive insulin secretion impairment, hepatic insulin resistance, renal cysts, and abnormal liver function tests.

Question 22

Which MODY subtype is caused by mutations in the glucokinase gene?
A. MODY 1
B. MODY 2
C. MODY 3
D. MODY 5

Answer 22

Correct Answer: B. MODY 2
Rationale: MODY 2 results from mutations in the glucokinase gene, affecting glucose sensing and insulin secretion.

Question 23

What characterizes Stage 1 of type 1 diabetes according to the temporal model for its development?
A. Hyperglycemia exceeding diagnostic criteria for diabetes
B. Development of islet cell autoantibodies without hyperglycemia
C. Reduced insulin secretion and symptomatic hyperglycemia
D. Progressive beta cell loss with impaired glucose tolerance

Answer 23

Correct Answer:
B. Development of islet cell autoantibodies without hyperglycemia

Rationale:
Stage 1 of type 1 diabetes is marked by the presence of two or more islet cell autoantibodies, which indicates an autoimmune process. However, at this stage, beta cell function is sufficient to maintain normal glucose levels, so hyperglycemia is not present.

Question 24

What defines Stage 3 of type 1 diabetes in the temporal model?
A. Normal glucose levels with immunologic abnormalities
B. Islet cell autoantibodies without loss of beta cell mass
C. Hyperglycemia meeting diagnostic criteria for diabetes
D. Stable beta cell function despite autoimmune progression

Answer 24

Correct Answer:
C. Hyperglycemia meeting diagnostic criteria for diabetes

Rationale:
Stage 3 is characterized by hyperglycemia that exceeds the diagnostic criteria for diabetes. This stage represents overt diabetes due to significant loss of beta cell mass and function, which is insufficient to maintain normal glucose levels.

Question 25

Question 3:
What happens to beta cell mass during the progression of type 1 diabetes?
A. It remains stable until hyperglycemia develops.
B. It progressively declines due to autoimmune destruction.
C. It increases in response to the immune trigger.
D. It fluctuates between stages without significant loss.

Answer 25

Correct Answer:
B. It progressively declines due to autoimmune destruction.

Rationale:
The model shows a gradual decline in beta cell mass as a result of autoimmune-mediated destruction, beginning with an immunologic trigger and progressing through the stages of diabetes.

Question 26

What is the target HbA1c goal for nonpregnant adults with diabetes according to the ADA guidelines?
A. <6.0% (42 mmol/mol)
B. <7.0% (53 mmol/mol)
C. <8.0% (64 mmol/mol)
D. <6.5% (48 mmol/mol)

Answer 26

Correct Answer:
B. <7.0% (53 mmol/mol)

Rationale:
For most nonpregnant adults with diabetes, the ADA recommends an HbA1c goal of <7.0% (53 mmol/mol) to reduce the risk of long-term complications. Individualization of targets is important based on patient-specific factors

Question 27

What is the preprandial capillary blood glucose target for older or high-risk adults with diabetes?
A. 4.4–7.2 mmol/L (80–130 mg/dL)
B. 5.0–7.8 mmol/L (90–140 mg/dL)
C. <10.0 mmol/L (180 mg/dL)
D. <11.1 mmol/L (200 mg/dL)

Answer 27

Correct Answer:
B. 5.0–7.8 mmol/L (90–140 mg/dL)

Rationale:
For older or high-risk adults, the preprandial blood glucose target is slightly higher to account for comorbidities and risk of hypoglycemia. The range of 5.0–7.8 mmol/L (90–140 mg/dL) aligns with ADA recommendations for this population.

Question 28

In nonpregnant adults, what percentage of time in range (3.9–10.0 mmol/L or 70–180 mg/dL) is recommended for optimal glycemic control?
A. >70%
B. >50%
C. <36%
D. >90%

Answer 28

Correct Answer:
A. >70%

Rationale:
Nonpregnant adults with diabetes are advised to maintain a time in range (3.9–10.0 mmol/L or 70–180 mg/dL) of greater than 70% as an indicator of optimal glycemic control. This metric is based on continuous glucose monitoring data.

Question 29

What is the upper limit for postprandial capillary blood glucose in older or high-risk adults?
A. <8.0 mmol/L (144 mg/dL)
B. <10.0 mmol/L (180 mg/dL)
C. <11.1 mmol/L (200 mg/dL)
D. <12.0 mmol/L (216 mg/dL)

Answer 29

Correct Answer:
C. <11.1 mmol/L (200 mg/dL)

Rationale:
The ADA sets a postprandial blood glucose target of <11.1 mmol/L (200 mg/dL) for older or high-risk adults to balance glycemic control with the risk of hypoglycemia and individual patient needs.

Question 30

What is the recommended glucose variability (coefficient of variation) target for nonpregnant adults with diabetes?
A. <25%
B. <30%
C. <36%
D. <40%

Answer 30

Correct Answer:
C. <36%

Rationale:
The ADA recommends keeping glucose variability (measured as the coefficient of variation) below 36% for better glycemic stability and to reduce the risk of complications. This metric is derived from continuous glucose monitoring data.

Question 31

What is the primary mechanism of action of metformin (a biguanide) in diabetes treatment?
A. Stimulates insulin secretion
B. Increases insulin sensitivity and reduces hepatic glucose production
C. Slows gastric emptying
D. Blocks renal glucose reabsorption

.

Answer 31

Correct Answer:
B. Increases insulin sensitivity and reduces hepatic glucose production

Rationale:
Metformin works by reducing hepatic glucose production, improving insulin sensitivity, and enhancing peripheral glucose uptake. It is weight-neutral, does not cause hypoglycemia, and is a first-line agent for type 2 diabetes

Question 32

Which class of oral diabetes medications is known to primarily block renal glucose reabsorption?
A. Sulfonylureas
B. α-Glucosidase inhibitors
C. Sodium-glucose cotransporter 2 (SGLT2) inhibitors
D. Thiazolidinediones

Answer 32

Correct Answer:
C. Sodium-glucose cotransporter 2 (SGLT2) inhibitors

Rationale:
SGLT2 inhibitors (e.g., canagliflozin, dapagliflozin) work by blocking glucose reabsorption in the renal tubules, promoting glycosuria. They also have additional benefits, such as weight loss and cardiovascular protection.

Question 33

Which diabetes medication class is contraindicated in heart failure due to its potential to cause fluid retention and exacerbate the condition?
A. Biguanides
B. Thiazolidinediones
C. α-Glucosidase inhibitors
D. GLP-1 receptor agonists

Answer 33

Correct Answer:
B. Thiazolidinediones

Rationale:
Thiazolidinediones (e.g., pioglitazone, rosiglitazone) increase insulin sensitivity but are contraindicated in patients with congestive heart failure (CHF) due to fluid retention and the risk of edema.

Question 34

Which medication class is associated with weight loss and also slows gastric emptying?
A. Insulin
B. α-Glucosidase inhibitors
C. GLP-1 receptor agonists
D. Sulfonylureas

Correct Answer:
C. GLP-1 receptor agonists

Answer 34

Rationale:
GLP-1 receptor agonists (e.g., liraglutide, semaglutide) promote weight loss by slowing gastric emptying, enhancing satiety, and reducing food intake. They do not cause hypoglycemia when used alone.

Question 35

Which of the following is an advantage of SGLT2 inhibitors in treating diabetes?
A. No risk of hypoglycemia and weight gain
B. Cardiovascular protection and blood pressure reduction
C. Increased insulin secretion
D. Reduced gastrointestinal side effects

Answer 35

Correct Answer:
B. Cardiovascular protection and blood pressure reduction

Rationale:
SGLT2 inhibitors provide benefits beyond glucose control, including cardiovascular protection, reduction in blood pressure, and weight loss. They do not cause hypoglycemia when used as monotherapy.

Question 36

According to the ADA, how much moderate aerobic physical activity should adults with diabetes aim to achieve per week?
A. 75 minutes over 3 days with no more than a 1-day gap
B. 150 minutes over 3 days with no gaps longer than 2 days
C. 200 minutes distributed over 5 days
D. 120 minutes distributed over 3 days

Answer 36

Correct Answer:
B. 150 minutes over 3 days with no gaps longer than 2 days

Rationale:
The American Diabetes Association recommends adults with diabetes engage in 150 minutes of moderate aerobic physical activity per week, spread over at least three days, with no gaps longer than two consecutive days to optimize glycemic control and cardiovascular health.

Question 37

Which of the following is a relative contraindication to vigorous exercise in individuals with diabetes?
A. Hypoglycemia (<5.0 mmol/L or <90 mg/dL)
B. Blood glucose >14 mmol/L (250 mg/dL) with ketones
C. Untreated proliferative retinopathy
D. Blood glucose between 7–10 mmol/L (126–180 mg/dL)

Answer 37

Correct Answer:
C. Untreated proliferative retinopathy

Rationale:
Untreated proliferative retinopathy is a relative contraindication to vigorous exercise because it can lead to vitreous hemorrhage or retinal detachment.

Question 38

Why are individuals with type 1 diabetes prone to hyperglycemia during exercise if insulin levels are too low?
A. Increased glucose uptake by muscles
B. Excessive ketone body formation and decreased liver lactate delivery
C. Increased catecholamine release and ketone body formation
D. Decreased glycogenolysis and hepatic glucose production

Answer 38

Correct Answer:
C. Increased catecholamine release and ketone body formation

Rationale:
Low insulin levels during exercise can lead to excessive catecholamine release, increased hepatic glucose production, and ketone body formation, potentially resulting in hyperglycemia or diabetic ketoacidosis.

Question 39

Which of the following strategies helps to avoid exercise-induced hypoglycemia in type 1 diabetes?
A. Injecting insulin into the exercising muscle group
B. Monitoring glucose levels before, during, and after exercise
C. Delaying exercise when glucose levels are >10 mmol/L (180 mg/dL)
D. Avoiding carbohydrate intake before exercise

Answer 39

Correct Answer:
B. Monitoring glucose levels before, during, and after exercise

Rationale:
To avoid exercise-related hyper- or hypoglycemia
* monitor blood glucose before, during, and after exercise
* delay exercise if blood glucose is >14 mmol/L (250 mg/ dL) and ketones are present
* if the blood glucose is <5.0 mmol/L (90 mg/dL), ingest carbohydrate before exercising
* monitor glucose during exercise and ingest carbohydrate as needed to prevent hypoglycemia
* decrease insulin doses (based on previous experience) before and after exercise and inject insulin into a nonexercising area
* learn individual glucose responses to different types of exercise

Question 40

What should individuals with diabetes do if their pre-exercise blood glucose is <5.0 mmol/L (90 mg/dL)?
A. Proceed with exercise without adjustment
B. Delay exercise and inject additional insulin
C. Ingest carbohydrates before exercising
D. Increase insulin dose before starting exercise

Answer 40

Correct Answer:
C. Ingest carbohydrates before exercising

Rationale:
If blood glucose levels are below 5.0 mmol/L (90 mg/dL) before exercise, individuals should ingest carbohydrates to prevent hypoglycemia during activity, as exercise increases glucose uptake by muscles.

Question 41

How often does the ADA recommend measuring HbA1c in individuals with diabetes?
A. Annually
B. Twice per year
C. Every 3 months
D. Monthly

Answer 41

Correct Answer:
B. Twice per year

Rationale:
The ADA recommends measuring HbA1c at least twice per year in patients with stable glycemic control. More frequent measurements may be required if therapy is changed or glycemic control is unstable.

Question 42

What is a major limitation of HbA1c measurement in certain clinical conditions?
A. It only reflects glycemic control for the prior 2 weeks.
B. It is affected by hemoglobinopathies and altered RBC turnover.
C. It is unreliable in detecting hyperglycemia.
D. It requires fasting for accurate results.

Answer 42

Correct Answer:
B. It is affected by hemoglobinopathies and altered RBC turnover.

Rationale:
* Clinical conditions leading to abnormal RBC parameters such as hemoglobinopathies, anemias, reticulocytosis, transfusions, and uremia may alter the HbA1c result.

Question 43

Which test reflects glycemic control over the past 2 weeks?
A. Glycated hemoglobin (HbA1c)
B. Fructosamine assay
C. Fasting plasma glucose
D. Continuous glucose monitoring (CGM)

Answer 43

Correct Answer:
B. Fructosamine assay

Rationale:
The fructosamine assay measures glycated albumin and reflects glycemic control over the previous 2 weeks. It is particularly useful when HbA1c is unreliable due to altered RBC turnover or other conditions.

Question 44

In which of the following scenarios should metformin be discontinued?
A. In patients with a GFR >60 mL/min
B. In hospitalized patients receiving radiographic contrast material
C. In patients experiencing mild gastrointestinal side effects
D. In patients with mild fasting hyperglycemia

Answer 44

Correct Answer:
B. In hospitalized patients receiving radiographic contrast material

Rationale:
Metformin should be discontinued in patients undergoing procedures involving radiographic contrast, in hospitalized patients unable to take oral medication, and in cases of moderate renal insufficiency (GFR <30 mL/min) due to the rare but serious risk of lactic acidosis.

Question 45

Which of the following is a common side effect of sulfonylureas?
A. Nausea and vomiting
B. Weight gain and hypoglycemia
C. Lactic acidosis
D. Hyperkalemia

Answer 45

Correct Answer:
B. Weight gain and hypoglycemia

Rationale:
Sulfonylureas increase insulin secretion, which can lead to weight gain and hypoglycemia, particularly with long-acting agents in elderly individuals.

Question 46

What advantage do GLP-1 receptor agonists have over sulfonylureas?
A. They are taken once monthly.
B. They enhance insulin secretion without risk of hypoglycemia.
C. They increase fasting glucose only.
D. They have no gastrointestinal side effects.

Answer 46

Correct Answer:
B. They enhance insulin secretion without risk of hypoglycemia.

Rationale:
GLP-1 receptor agonists increase glucose-stimulated insulin secretion, suppress glucagon, and slow gastric emptying. Because they enhance insulin secretion in a glucose-dependent manner, the risk of hypoglycemia is minimal unless combined with other hypoglycemic agents.

Question 47

What is a potential serious adverse effect of GLP-1 receptor agonists and DPP-IV inhibitors?
A. Hepatic failure
B. Acute pancreatitis
C. Renal insufficiency
D. Cardiovascular events

Answer 47

Correct Answer:
B. Acute pancreatitis

Rationale:
There is evidence of an increased risk of acute pancreatitis with GLP-1 receptor agonists and, to a lesser extent, DPP-IV inhibitors. These agents should be avoided in patients with a history of pancreatic disease or significant risk factors for pancreatitis.

Question 48

What is the primary mechanism of action of thiazolidinediones in managing type 2 diabetes?
A. Enhancing GLP-1 receptor activity
B. Reducing hepatic glucose production
C. Binding to PPAR-γ to reduce insulin resistance
D. Stimulating insulin secretion from pancreatic beta cells

Answer 48

Correct Answer:
C. Binding to PPAR-γ to reduce insulin resistance

Rationale:
Thiazolidinediones improve insulin sensitivity by binding to the peroxisome proliferator-activated receptor γ (PPAR-γ) nuclear receptor, which modulates gene expression involved in glucose and lipid metabolism.

Question 49

n which of the following scenarios are thiazolidinediones contraindicated?
A. Mild renal insufficiency
B. Class III or IV congestive heart failure (CHF)
C. Type 2 diabetes with central obesity
D. Postmenopausal women with low bone density

Answer 49

Correct Answer:
B. Class III or IV congestive heart failure (CHF)

Rationale:
Thiazolidinediones are contraindicated in patients with class III or IV CHF due to the risk of fluid retention and worsening heart failure.

Question 50

What laboratory test should be performed prior to initiating thiazolidinedione therapy?
A. Serum creatinine
B. Hemoglobin A1c
C. Liver function tests
D. Lipid profile

Answer 50

Correct Answer:
C. Liver function tests

Rationale:
The FDA recommends liver function tests before initiating thiazolidinedione therapy due to the potential for hepatotoxicity.

Question 51

What is the primary mechanism of action of SGLT2 inhibitors in lowering blood glucose?
A. Inhibiting hepatic glucose production
B. Increasing insulin secretion
C. Inhibiting glucose reabsorption in the renal proximal tubule
D. Enhancing glucose uptake in peripheral tissues

Answer 51

Correct Answer:
C. Inhibiting glucose reabsorption in the renal proximal tubule

Rationale:
SGLT2 inhibitors lower blood glucose levels by selectively inhibiting the sodium-glucose co-transporter 2 (SGLT2) in the proximal tubule of the kidney, preventing glucose reabsorption and promoting urinary glucose excretion.

Question 52

What additional benefit, aside from glucose lowering, is commonly observed with SGLT2 inhibitors?
A. Increased muscle mass
B. Modest weight loss and reduced systolic blood pressure
C. Improved liver function tests
D. Increased insulin sensitivity

Answer 52

Correct Answer:
B. Modest weight loss and reduced systolic blood pressure

Rationale:
The urinary excretion of glucose promotes modest weight loss, while the diuretic effect of SGLT2 inhibitors leads to a 3–6 mmHg reduction in systolic blood pressure.

Question 53

Which of the following adverse effects is most commonly associated with SGLT2 inhibitors?
A. Diabetic ketoacidosis
B. Mycotic infections and volume depletion
C. Pancreatitis
D. Hypoglycemia

Answer 53

Correct Answer:
B. Mycotic infections and volume depletion

Rationale:
SGLT2 inhibitors increase urinary glucose excretion, creating a favorable environment for genital and urinary mycotic infections. The diuretic effect can lead to volume depletion and, in some cases, acute kidney injury.

Question 54

In which of the following patient scenarios is the use of SGLT2 inhibitors contraindicated?
A. A patient with mild renal insufficiency (eGFR 60 mL/min per 1.73 m²)
B. A patient with type 2 diabetes and hypertension
C. A patient with stage 4 chronic kidney disease (eGFR <30 mL/min per 1.73 m²)
D. A patient with heart failure with reduced ejection fraction (HFrEF)

Answer 54

Correct Answer:
C. A patient with stage 4 chronic kidney disease (eGFR <30 mL/min per 1.73 m²)

Rationale:
SGLT2 inhibitors should not be used in patients with stage 4 CKD (eGFR <30 mL/min per 1.73 m²) and should not be initiated in patients with stage 3b CKD (eGFR <45 mL/min per 1.73 m²).

Question 55

What is the leading cause of blindness in individuals aged 20–74 in the United States?
A. Glaucoma
B. Cataracts
C. Diabetic retinopathy
D. Age-related macular degeneration

Answer 55

Correct Answer:
C. Diabetic retinopathy

Rationale:
Diabetic retinopathy, a complication of diabetes mellitus, is the leading cause of blindness among individuals aged 20–74 in the United States. Severe vision loss results from progressive retinopathy, macular edema, and neovascularization.

Question 56

What is the hallmark of proliferative diabetic retinopathy?
A. Retinal microaneurysms
B. Neovascularization in response to retinal hypoxemia
C. Cotton-wool spots
D. Blot hemorrhages

Answer 56

Correct Answer:
B. Neovascularization in response to retinal hypoxemia

Rationale:
Proliferative diabetic retinopathy is characterized by the formation of new blood vessels (neovascularization) near the optic nerve and/or macula. These vessels rupture easily, leading to vitreous hemorrhage, fibrosis, and retinal detachment.

Question 57

What is the most effective strategy for managing diabetic retinopathy?
A. Early surgical vitrectomy
B. Prophylactic laser photocoagulation for all patients
C. Prevention through glycemic and blood pressure control
D. Anti-VEGF therapy for all diabetic patients

Answer 57

Correct Answer:
C. Prevention through glycemic and blood pressure control

Rationale:
The most effective management of diabetic retinopathy is prevention by maintaining good glycemic and blood pressure control to reduce the risk of progression.

Question 58

Which of the following treatments is most appropriate for severe proliferative diabetic retinopathy with vitreous hemorrhage?
A. Anti-VEGF therapy
B. Laser photocoagulation alone
C. Surgical vitrectomy
D. Retinal transplant

Answer 58

Correct Answer:
C. Surgical vitrectomy

Rationale:
Surgical vitrectomy is often required for patients with severe proliferative retinopathy complicated by vitreous hemorrhage and/or macular traction.

Question 59

What is the leading cause of chronic kidney disease (CKD) and end-stage renal disease (ESRD) requiring renal replacement therapy?
A. Hypertension
B. Polycystic kidney disease
C. Diabetic nephropathy
D. Glomerulonephritis

Answer 59

Correct Answer:
C. Diabetic nephropathy

Rationale:
Diabetic nephropathy is the most common cause of CKD and ESRD, resulting from prolonged hyperglycemia and associated renal damage.

Question 60

The presence of CKD in individuals with diabetes and no diabetic retinopathy suggests what course of action?
A. Immediate initiation of SGLT-2 inhibitors
B. Further investigation for alternative causes of kidney disease
C. Routine monitoring of albuminuria only
D. Treatment with mineralocorticoid receptor antagonists

Answer 60

Correct Answer:
B. Further investigation for alternative causes of kidney disease

Rationale:
The absence of diabetic retinopathy in a diabetic patient with CKD raises suspicion of an alternative etiology for kidney disease, necessitating further evaluation.

Question 61

When should screening for albuminuria begin in individuals with diabetes?
A. At the time of diagnosis of type 1 diabetes mellitus
B. Five years after the onset of type 1 diabetes mellitus
C. At the time of diagnosis of type 2 diabetes mellitus
D. Both B and C

Answer 61

Correct Answer:
D. Both B and C

Rationale:
Screening for albuminuria begins 5 years after the onset of type 1 diabetes mellitus but at the time of diagnosis for type 2 diabetes mellitus due to its typically delayed detection.

Question 62

What is the recommended target blood pressure for individuals with diabetes and CKD?
A. <150/90 mmHg
B. <140/90 mmHg
C. <130/80 mmHg
D. Both B and C, depending on risk factors

Answer 62

Correct Answer:
D. Both B and C, depending on risk factors

Rationale:
The ADA recommends maintaining blood pressure <140/90 mmHg in individuals with diabetes, while a stricter target of <130/80 mmHg is advised for those at increased risk of cardiovascular disease or CKD progression.

Question 63

What is the ADA’s recommended protein intake for individuals with diabetic kidney disease?
A. 0.6 mg/kg of body weight/day
B. 0.8 mg/kg of body weight/day
C. 1.0 mg/kg of body weight/day
D. 1.2 mg/kg of body weight/day

Answer 63

Correct Answer:
B. 0.8 mg/kg of body weight/day

Rationale:
The ADA recommends a protein intake of 0.8 mg/kg of body weight/day in individuals with diabetic kidney disease to limit renal stress and progression of nephropathy.