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Statin therapy causes what substance deficiency?

3K views 13 replies 11 participants last post by  Casandra 
#1 ·
At his annual physical examination, a 59-year-old man complains of aching in his thighs that occurs during his 5-mile morning runs. He has made no significant changes in the length or speed of the running schedule. The patient has a history of elevated blood lipids and has been taking a standard daily dose of a statin drug for the past 2 years. A routine laboratory profile is normal, but the creatine phosphokinase (CPK) value is elevated. A deficiency in which of the following substances created by the statin drug is causing the patient’s symptoms?

a) Cholesterol
b) Dehydroepiandrosterone
c) Isoprene
d) Vitamin D
 
#13 ·
At his annual physical examination, a 59-year-old man complains of aching in his thighs that occurs during his 5-mile morning runs. He has made no significant changes in the length or speed of the running schedule. The patient has a history of elevated blood lipids and has been taking a standard daily dose of a statin drug for the past 2 years. A routine laboratory profile is normal, but the creatine phosphokinase (CPK) value is elevated. A deficiency in which of the following substances created by the statin drug is causing the patient’s symptoms?

a) Cholesterol
 
#14 ·
correct answer :)

The correct answer is c) Isoprene

The question was asking about the deficiency related to the symptoms/side effects of the statins - elevated CK-MB = muscle destruction. Low level cholesterol is not the cause. Deficiency in Q10 is.

The official explanation:
Ten isoprene units are needed to form the tail on coenzyme Q10. A deficiency in isoprene in the cholesterol pathway would create a coenzyme Q10 deficiency and impair energy metabolism in muscle.
 
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