Endocrine Weight Loss Endocrine Pathology 4 — Questions and Answers
Question 1: Which gut-derived hormone rises before meals and stimulates appetite, making it a key target for weight-loss therapies?
- GLP-1
- Ghrelin (Correct answer)
- Peptide YY
- Cholecystokinin
Correct answer: Ghrelin
Ghrelin is released by the stomach when fasting and acts on the hypothalamus to stimulate hunger; it falls after eating.
Question 2: A patient with weight gain, fatigue, constipation, and a TSH of 12 mIU/L is started on levothyroxine. What is the primary goal of treatment regarding weight?
- Achieve BMI < 18.5 rapidly
- Restore euthyroid state so metabolic rate normalizes, allowing gradual weight loss (Correct answer)
- Suppress TSH below normal range to maximize weight loss
- Replace T3 exclusively for faster metabolic effect
Correct answer: Restore euthyroid state so metabolic rate normalizes, allowing gradual weight loss
Levothyroxine restores normal thyroid hormone levels, normalizing metabolic rate; significant weight loss beyond the fluid and metabolic correction is not guaranteed.
Question 3: In type 2 diabetes, which class of medication both lowers blood glucose AND promotes significant weight loss by mimicking an incretin hormone?
- Sulfonylureas
- GLP-1 receptor agonists (Correct answer)
- Meglitinides
- Thiazolidinediones
Correct answer: GLP-1 receptor agonists
GLP-1 receptor agonists (e.g., semaglutide, liraglutide) mimic GLP-1 to lower glucose, delay gastric emptying, and reduce appetite, causing meaningful weight loss.
Question 4: Subclinical hypothyroidism (elevated TSH with normal free T4) is MOST likely to cause which magnitude of weight change?
- Severe weight gain of 20+ lbs
- Modest weight gain of 2–5 lbs, primarily from fluid retention (Correct answer)
- Significant weight loss
- No change in weight
Correct answer: Modest weight gain of 2–5 lbs, primarily from fluid retention
Subclinical hypothyroidism typically causes only modest weight gain (mostly fluid), as thyroid hormone levels are still in the normal range.
Question 5: Which genetic endocrine disorder causes severe early-onset obesity due to MC4R (melanocortin-4 receptor) mutations?
- Turner syndrome
- Monogenic MC4R-deficiency obesity (Correct answer)
- Prader-Willi syndrome
- Bardet-Biedl syndrome
Correct answer: Monogenic MC4R-deficiency obesity
Loss-of-function mutations in MC4R impair the hypothalamic satiety signaling pathway, causing severe hyperphagia and early-onset obesity.
Question 6: A postmenopausal woman notices increased abdominal fat despite no change in diet. Which hormonal change most directly explains this shift in fat distribution?
- Rising FSH redistributing fat centrally
- Declining estrogen reducing peripheral fat storage and promoting central accumulation (Correct answer)
- Rising LH increasing cortisol production
- Declining progesterone causing water retention
Correct answer: Declining estrogen reducing peripheral fat storage and promoting central accumulation
Estrogen normally promotes gluteal-femoral fat storage; its postmenopausal decline shifts fat distribution toward the visceral/central compartment.
Question 7: Which finding on an oral glucose tolerance test (OGTT) is diagnostic of insulin resistance even when fasting glucose is normal?
- 2-hour glucose of 100 mg/dL
- Exaggerated insulin response with 2-hour glucose of 140–199 mg/dL (prediabetes range) (Correct answer)
- Flat glucose curve with no insulin rise
- 2-hour glucose below 70 mg/dL
Correct answer: Exaggerated insulin response with 2-hour glucose of 140–199 mg/dL (prediabetes range)
In insulin resistance, the pancreas secretes excess insulin to maintain near-normal glucose, producing a high insulin-to-glucose ratio on OGTT in the prediabetes glucose range.
Endocrine Weight Loss Endocrine Pathology 4
Which gut-derived hormone rises before meals and stimulates appetite, making it a key target for weight-loss therapies?