In older adults receiving cyclic parenteral nutrition, which metabolic change is most likely compared to middle-aged adults?

• A. Insulin resistance leading to lower glucose utilization and hyperglycemia
• B. Lower concentrations of free fatty acids
• C. Lower fat oxidation and lower glucose oxidation
• D. Increased needs for fluid restriction

Answer: (A)

As people age, their tissues become less responsive to insulin, so glucose isn’t taken up as efficiently. In cyclic parenteral nutrition, a regular glucose infusion challenges the body, and if insulin action is blunted by aging, that glucose isn’t utilized well, leading to higher blood glucose levels. This combination—reduced glucose utilization with resulting hyperglycemia—best fits what you’d expect in older adults compared with middle-aged adults.

Lower free fatty acids would be unlikely because insulin resistance usually allows lipolysis to proceed more, raising FFAs rather than lowering them. The idea of both lower fat and glucose oxidation isn’t the typical, direct pattern seen with aging and PN, and increased needs for fluid restriction isn’t a metabolic change related to aging.