Casting Bitwise struct to Integer

I have bitwise structure with a bunch of flags.

struct {

  uint8_t a: 4; 

  uint8_t b: 4; 

} _tVarA

_tVarA Var_A = {0,0};

But when I want to view them as a whole integer, I need to cast it like this:

                               *(uint8_t*)&Var_A

ref:
http://www.avrfreaks.net/forum/casting-bitfield-struct-integer
https://stackoverflow.com/questions/11903820/casting-struct-into-int