It sounds like something in your code is confusing our parser. Is this a local variable, a class member variable, a global variable? If you change files and change back, and run Find References on the namespace, does VA still pick up the variable name as well?
I have tried the following very simple example:
int nTotal, testDoubleName;
nTotal = 2;
testDoubleName = 3;
nTotal += testDoubleName;
and VA does not pick up the variable here when I trigger a Find References or Rename on the namespace name. So I am wondering what there is in your code that is confusing our parser.