No it is not. This is why you shouldn't post code snippets in the forum.
Put your full code (enough to reproduce the problem) on github.
If you are just extending the default Item class (we don't know what you extend) the above line of code will return PASS on the client and the server side code will never run.
So what code you are actually running is unknown.
You should really be using
InteractionResult.sidedSuccess(level.isClientSide)
unless you really do want the code in the super class to run.
As the to the integer, I assume you mean the flags found in the Block class?
The destroyBlock() method you call uses 3 which is UPDATE_NEIGHBORS and UPDATE_CLIENTS. That is usually what you want unless you have special requirements.