Which factor leads to lower sodium results in lipemic samples?

Pseudohyponatremia due to dilution is the correct choice because lipemic samples contain a high concentration of triglycerides, which can interfere with the measurement of sodium levels in certain analytical methods. In these instances, the presence of excess lipids can lead to a false reduction in the measured sodium concentration, a condition known as pseudohyponatremia.

When blood is lipemic, the lipids can expand the plasma volume disproportionately compared to the actual sodium content, creating a dilutional effect. As a result, sodium concentrations appear lower than they truly are. This phenomenon emphasizes the importance of recognizing and addressing sample interference due to lipemia when interpreting sodium results, especially in clinical settings where accurate electrolyte levels are critical for patient management.

Other potential factors, such as increased viscosity affecting readings or the presence of unmeasured solutes, may have some role in the context of lipemia; however, they do not specifically lead to the classic laboratory error of pseudohyponatremia. Improper specimen handling can affect sample integrity and lead to various artifacts, but it is not the primary reason for the lower sodium results seen in lipemic samples. Understanding these mechanisms is crucial for healthcare professionals when assessing electrolyte levels in patients with lipid abnormalities.