That doesn't really help if there actually is a memory leak somewhere. It just delays the inevitable.
Note, however, that there are many subsystems involved in playing a game like EU2, any each one of them can have problems. It may be a memory leak in EU2 itself (probable, but not very likely if it wasn't there before in previous patches), it may be a resource leak, and it can be either in the video driver, the sound driver, dirext X itself, just to name a few.
If you suspect a memory leak, then run the system/resource monitor alongside EU2, setup an indicator for total allocated memory, and check periodicly if the number goes up when you play the game. Or, if you happen to run on Windows NT or higher, check the memory allocated to the EU2 process in the task manager and see if that number goes up steadily.
One note in advance. It is normal that the total memory goes up slightly as you advance through the years in an actual game. That is because the game steadily increases the history (all those logged events, stored near the bottom of a save game), and that has to be stored somewhere.
Jan Peter