SCE ENDOCRINOLOGY & DIABETES COMPREHENSIVE REVISION EXAM 2025/2026
SECTION A: TYPE 2 DIABETES MELLITUS – PATHOPHYSIOLOGY AND DIAGNOSIS
1. A 52-year-old man with BMI 31 kg/m² undergoes an OGTT. Fasting glucose is 6.4
mmol/L and 2-hour glucose is 9.2 mmol/L. What is the correct classification?
(A) Normal glucose tolerance
(B) Impaired fasting glucose only
(C) Impaired glucose tolerance
(D) Diabetes mellitus
Answer: (C)
Rationale: 2-hour OGTT glucose of 7.8–11.0 mmol/L defines impaired glucose tolerance.
Fasting glucose 6.1–6.9 mmol/L is IFG, but the 2-hour value takes precedence for IGT
classification.
2. Which pathophysiological defect is NOT part of DeFronzo's "Ominous Octet" in type
2 diabetes?
(A) Increased glucagon secretion
(B) Enhanced incretin effect
(C) Increased renal glucose reabsorption
(D) Neurotransmitter dysfunction
Answer: (B)
Rationale: The incretin effect is diminished, not enhanced, in T2DM. The eight defects
include muscle/liver/adipocyte insulin resistance, beta-cell failure, alpha-cell excess,
incretin defect, renal glucose reabsorption, and neurotransmitter dysfunction.
,3. A 38-year-old woman has HbA1c of 6.3% (45 mmol/mol). What is the most
appropriate classification and follow-up?
(A) Normal; repeat in 3 years
(B) Prediabetes; annual testing
(C) Diabetes; start metformin
(D) Impaired fasting glucose; repeat in 6 months
Answer: (B)
Rationale: HbA1c 5.7–6.4% (39–47 mmol/mol) indicates prediabetes. ADA recommends
annual testing for individuals with prediabetes. Lifestyle intervention is first-line.
4. Which statement reflects the natural history of beta-cell function in type 2 diabetes
at diagnosis?
(A) Approximately 10% of beta-cell mass is lost
(B) Approximately 50% of beta-cell mass is lost
(C) Beta-cell mass is preserved but function impaired
(D) Beta-cell mass is normal until complications develop
Answer: (B)
Rationale: By the time of T2DM diagnosis, approximately 50% of beta-cell mass has been
lost. Progressive apoptosis exceeds neogenesis throughout the disease course.
5. A 45-year-old man with hypertension and BMI 29 kg/m² has no diabetes symptoms.
When should screening begin according to ADA 2025 Standards?
(A) Age 35
(B) Age 40
(C) Age 45
(D) Only if symptomatic
Answer: (A)
Rationale: ADA 2025 recommends screening for prediabetes and T2DM beginning at age 35
for all individuals, and earlier for those with overweight/obesity plus one or more risk
factors.
,6. In the UKPDS study, which factor was most strongly associated with microvascular
complications in T2DM?
(A) Blood pressure control
(B) Glycaemic control (HbA1c)
(C) Lipid profile
(D) Smoking cessation
Answer: (B)
Rationale: UKPDS demonstrated that each 1% reduction in HbA1c was associated with a
37% decrease in microvascular complications, establishing glycaemic control as central to
reducing microvascular risk.
7. A patient has fasting glucose of 7.2 mmol/L on two occasions. What is the
diagnosis?
(A) Impaired fasting glucose
(B) Diabetes mellitus
(C) Normal glucose tolerance
(D) Requires OGTT for confirmation
Answer: (B)
Rationale: Two fasting plasma glucose values ≥7.0 mmol/L confirm diabetes mellitus
without need for OGTT. A single diagnostic test requires confirmation unless unequivocal
hyperglycaemia with symptoms is present.
8. Which mechanism explains the paradoxical postprandial hyperglycaemia in early
T2DM despite elevated insulin levels?
(A) Increased hepatic glucose uptake
(B) Alpha-cell dysfunction with inappropriate glucagon secretion
(C) Enhanced peripheral insulin sensitivity
(D) Increased renal glucose threshold
Answer: (B)
Rationale: Alpha-cell dysregulation causes paradoxical hyperglucagonaemia after meals,
worsening postprandial hyperglycaemia even in the presence of compensatory
hyperinsulinaemia.
, SECTION B: TYPE 2 DIABETES – PHARMACOLOGICAL MANAGEMENT
9. A 58-year-old man with T2DM, HbA1c 7.8%, BMI 32 kg/m², and established ASCVD.
He is on metformin. What is the most appropriate add-on therapy?
(A) Sulphonylurea
(B) DPP-4 inhibitor
(C) GLP-1 receptor agonist
(D) Pioglitazone
Answer: (C)
Rationale: In T2DM with established ASCVD, GLP-1 RA or SGLT2 inhibitor with proven
cardiovascular benefit is recommended independent of HbA1c. GLP-1 RAs are preferred by
AACE for ASCVD.
10. A 62-year-old woman with T2DM and HFrEF (EF 35%). Which glucose-lowering
agent provides mortality benefit?
(A) Metformin
(B) SGLT2 inhibitor
(C) Sulphonylurea
(D) Insulin
Answer: (B)
Rationale: SGLT2 inhibitors are recommended for patients with T2DM and heart failure
(both HFrEF and HFpEF) based on level A evidence demonstrating reduced hospitalisation
for heart failure and cardiovascular mortality.
11. What is the recommended starting dose of metformin in a patient with eGFR 42
mL/min/1.73m²?
(A) Metformin contraindicated
(B) 500 mg once daily
(C) 850 mg twice daily
(D) 1000 mg twice daily
SECTION A: TYPE 2 DIABETES MELLITUS – PATHOPHYSIOLOGY AND DIAGNOSIS
1. A 52-year-old man with BMI 31 kg/m² undergoes an OGTT. Fasting glucose is 6.4
mmol/L and 2-hour glucose is 9.2 mmol/L. What is the correct classification?
(A) Normal glucose tolerance
(B) Impaired fasting glucose only
(C) Impaired glucose tolerance
(D) Diabetes mellitus
Answer: (C)
Rationale: 2-hour OGTT glucose of 7.8–11.0 mmol/L defines impaired glucose tolerance.
Fasting glucose 6.1–6.9 mmol/L is IFG, but the 2-hour value takes precedence for IGT
classification.
2. Which pathophysiological defect is NOT part of DeFronzo's "Ominous Octet" in type
2 diabetes?
(A) Increased glucagon secretion
(B) Enhanced incretin effect
(C) Increased renal glucose reabsorption
(D) Neurotransmitter dysfunction
Answer: (B)
Rationale: The incretin effect is diminished, not enhanced, in T2DM. The eight defects
include muscle/liver/adipocyte insulin resistance, beta-cell failure, alpha-cell excess,
incretin defect, renal glucose reabsorption, and neurotransmitter dysfunction.
,3. A 38-year-old woman has HbA1c of 6.3% (45 mmol/mol). What is the most
appropriate classification and follow-up?
(A) Normal; repeat in 3 years
(B) Prediabetes; annual testing
(C) Diabetes; start metformin
(D) Impaired fasting glucose; repeat in 6 months
Answer: (B)
Rationale: HbA1c 5.7–6.4% (39–47 mmol/mol) indicates prediabetes. ADA recommends
annual testing for individuals with prediabetes. Lifestyle intervention is first-line.
4. Which statement reflects the natural history of beta-cell function in type 2 diabetes
at diagnosis?
(A) Approximately 10% of beta-cell mass is lost
(B) Approximately 50% of beta-cell mass is lost
(C) Beta-cell mass is preserved but function impaired
(D) Beta-cell mass is normal until complications develop
Answer: (B)
Rationale: By the time of T2DM diagnosis, approximately 50% of beta-cell mass has been
lost. Progressive apoptosis exceeds neogenesis throughout the disease course.
5. A 45-year-old man with hypertension and BMI 29 kg/m² has no diabetes symptoms.
When should screening begin according to ADA 2025 Standards?
(A) Age 35
(B) Age 40
(C) Age 45
(D) Only if symptomatic
Answer: (A)
Rationale: ADA 2025 recommends screening for prediabetes and T2DM beginning at age 35
for all individuals, and earlier for those with overweight/obesity plus one or more risk
factors.
,6. In the UKPDS study, which factor was most strongly associated with microvascular
complications in T2DM?
(A) Blood pressure control
(B) Glycaemic control (HbA1c)
(C) Lipid profile
(D) Smoking cessation
Answer: (B)
Rationale: UKPDS demonstrated that each 1% reduction in HbA1c was associated with a
37% decrease in microvascular complications, establishing glycaemic control as central to
reducing microvascular risk.
7. A patient has fasting glucose of 7.2 mmol/L on two occasions. What is the
diagnosis?
(A) Impaired fasting glucose
(B) Diabetes mellitus
(C) Normal glucose tolerance
(D) Requires OGTT for confirmation
Answer: (B)
Rationale: Two fasting plasma glucose values ≥7.0 mmol/L confirm diabetes mellitus
without need for OGTT. A single diagnostic test requires confirmation unless unequivocal
hyperglycaemia with symptoms is present.
8. Which mechanism explains the paradoxical postprandial hyperglycaemia in early
T2DM despite elevated insulin levels?
(A) Increased hepatic glucose uptake
(B) Alpha-cell dysfunction with inappropriate glucagon secretion
(C) Enhanced peripheral insulin sensitivity
(D) Increased renal glucose threshold
Answer: (B)
Rationale: Alpha-cell dysregulation causes paradoxical hyperglucagonaemia after meals,
worsening postprandial hyperglycaemia even in the presence of compensatory
hyperinsulinaemia.
, SECTION B: TYPE 2 DIABETES – PHARMACOLOGICAL MANAGEMENT
9. A 58-year-old man with T2DM, HbA1c 7.8%, BMI 32 kg/m², and established ASCVD.
He is on metformin. What is the most appropriate add-on therapy?
(A) Sulphonylurea
(B) DPP-4 inhibitor
(C) GLP-1 receptor agonist
(D) Pioglitazone
Answer: (C)
Rationale: In T2DM with established ASCVD, GLP-1 RA or SGLT2 inhibitor with proven
cardiovascular benefit is recommended independent of HbA1c. GLP-1 RAs are preferred by
AACE for ASCVD.
10. A 62-year-old woman with T2DM and HFrEF (EF 35%). Which glucose-lowering
agent provides mortality benefit?
(A) Metformin
(B) SGLT2 inhibitor
(C) Sulphonylurea
(D) Insulin
Answer: (B)
Rationale: SGLT2 inhibitors are recommended for patients with T2DM and heart failure
(both HFrEF and HFpEF) based on level A evidence demonstrating reduced hospitalisation
for heart failure and cardiovascular mortality.
11. What is the recommended starting dose of metformin in a patient with eGFR 42
mL/min/1.73m²?
(A) Metformin contraindicated
(B) 500 mg once daily
(C) 850 mg twice daily
(D) 1000 mg twice daily
