Final answer:
The nurse should prioritize discussing the importance of seeking immediate medical help if any signs or symptoms of a stroke recur.
Step-by-step explanation:
The priority for the nurse to discuss with the older adult client who lives alone and has left-sided weakness following a stroke is the importance of seeking immediate medical help if any signs or symptoms of a stroke recur. The nurse should emphasize the importance of recognizing the signs of a stroke using the FAST acronym: Face weakness, Arm weakness, Speech difficulties, and Time to call for help.