Cholesterol is described as a secondary test for two functions; which results are correct?

• A. Liver Function Test - proportional; Thyroid Function Test - inverse
• B. Liver Function Test - inverse; Thyroid Function Test - proportional
• C. Liver Function Test - inverse; Thyroid Function Test - inverse
• D. Liver Function Test - proportional; Thyroid Function Test - proportional

Answer: (A)

Cholesterol can reflect how other organs handle metabolism, so its direction of change relative to different functions can differ.

For liver function, cholesterol often changes in step with certain patterns of liver dysfunction, such as cholestasis, where bile flow is impaired and cholesterol clearance is affected. In these contexts, cholesterol levels tend to rise as liver function is affected, giving a proportional relationship with liver function test abnormalities.

For thyroid function, thyroid hormones regulate lipid metabolism and clearance. When thyroid activity is reduced (hypothyroidism), cholesterol levels tend to rise; when thyroid activity is increased (hyperthyroidism), cholesterol levels tend to fall. That makes the cholesterol–thyroid relationship inverse.

So describing cholesterol as proportional to liver function tests and inverse to thyroid function tests aligns with these opposing relationships, making it the best choice.