NBME 20 Cortisol (NBME Answers)

NBME 20 Answers

nbme20/Block 2/Question#30 (reveal difficulty score)
A 78-year-old man is brought to the emergency ...
Cortisol 🔍 / 📺 / 🌳 / 📖
tags: pathoma endo repeat

+9 upvote downvote
submitted by ∗hayayah(1212)

He's not eating enough.

One of cortisol's functions is to increase gluconeogenesis, lipolysis, and proteolysis.

ankirin Why wouldn't it be T3? Thyroid hormones also ↑blood sugar and break down lipids +1

waterloo @ankirin his symptoms aren't really specific for T3. They don't mention tremors, exopthalmos etc. I think just in physiologic terms, you can bet cortisol is more increased. It's not a great question though imo +

rockodude can someone comment on why his appetite is down, per first aid 2019, page 329, cortisol increases appetite. thank you +

lifeisruff his daughter isnt there to bring him groceries +

medstudent22 T3 levels decrease in states of starvation in an attempt to preserve energy. T3 is incredibly metabolically potent - even more so than T4. By decreasing peripheral conversion of T4 to T3 (ie decreasing T3 levels), you are decreasing metabolic activity in "unnecessary tissues", decreasing ATP use, and increasing overall energy availability for necessary tissues (brain). On a side note, rT3 levels may increase but this is not metabolically active and will not be measured as an elevation of T3. Dr. Ryan had a great explanation of this in one of his thyroid videos. https://pubmed.ncbi.nlm.nih.gov/12055988/ +1

+3 upvote downvote
submitted by ∗youssefa(162)

From Faid 2019 new figure: IGF-1 mainly functions as an anabolic hormone on muscles and bones (pretty much like insulin-> decreases serum glucose). GH acts separately by promoting insulin resistance (increasing serum glucose). Therefore, IGF-1 is not the answer. If GH was among the answers it would have got really confusing.

charcot_bouchard Can anyone take a little time to curse on that daughter? +6

dbg Sure, charcot. Just wished on her to get a couple of charcots (the triad, your aneuryms, marie tooth, etc). +2

noorahsaahir Charcot_bouchard and dbg best comments .... 🤣🤣🤣🤣🤣 +

feanor I hope she gets anal ulcers and ascaris both at the same time. Imagine the worms laying their eggs on top of em while she sleeps with the guilt. +

+2 upvote downvote
submitted by rio19111(16)

I think a lot of you missed the point. The answer is Cortisol because it helps maintain blood pressure even in the setting where he is malnourished.

rio19111 FA 2019, Pg. 329 +3

pakimd according to pathoma, cortisol is the hormone neccessary for life. in a condition like the one presented in the Q-stem the most important hormone will be cortisol. +3

pontiacfever Also Cortisol is generally a stress hormone. Starved body is generally understress--Cortisol +1

+0 upvote downvote
submitted by ∗stepwarrior(29)

Looked this up. Starvation causes GH resistance. Never heard of this, unfortunately fell into the trap of thinking increased GH would increase IGF-1. Punished for overthinking.

bgreen27 Ok, from what I understand, starvation may induce GH resistance, but starvation STILL stimulates its production. The question asked which hormone would be increased in concentration, so this doesn't really explain why IGF1 is wrong. One possible explanation I found is that AGING inhibits GH secretion, which is not the case for cortisol. +1

drdoom It makes evolutionary sense that if your body is in starvation mode it is not going to be releasing an ANABOLIC signal (Growth Hormone). If you're starving, you'll need to stop “putting on mass” and continue to catabolize fatty acids, glycogen and whatever other stores your body has left. (It will have to way away at itself simply to generate enough ATP for vital functions [fuel for heart, brain, kidney].) +1

drdoom eat* away +1

bgreen27 I totally get where youre coming from, but the fact is that starvation DOES increase release of GH (but apparently also increases GH resistance). So my qualm was with the question stem asking about which one increases in concentration, and GH and cortisol both increase during starvation. Have you found something different? +1

+0 upvote downvote
submitted by asdfghjkl(5)

Anyone know why IGF-1 wouldn't be increased as well? GHRH is stimulated in hypoglycemic states.

nala_ula Honestly, it's something that has confused me for a while. Why is it that GH secretion is stimulated by hypoglycemia? I mean, it's literally called growth hormone (for growth!), and hypoglycemia, which is basically a "starvation" state, will stimulate this hormone? +

shaeking https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3529368/ This might help answer your question. I basically didn't pick IGF-1 because it would increase the uptake of glucose leading to a worsen hypoglycemic state. Didn't have a true reason otherwise. +

temmy IGF-1 is regulated by insulin. so it will be decreased because insulin levels are also low. +2

nala_ula thank you @shaeking! +

nwinkelmann I found this and it also explains to a more genetic/cellular level. Essentially, it says that starvation induces some factors that cause GH resistance and IGF1 suppression. +1

nwinkelmann Sorry forgot the link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2575072/ +

+0 upvote downvote
submitted by ∗an1(114)

I just used common sense to rune out the answers here. Firstly, knowing that cortisol is increased during times of stress (starvation; like this stem). Insulin causes hypoglycaemia so the body wouldn't produce more in a stressful state (expect glycogen to be higher). IGF-1 acts like GH and these states of growth require energy which this man clearly doesn't have. There wasn't enough to support testosterone and T3 changes so those were ruled out pretty quick.

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