"Is age a barrier to a diagnosis?"

Do older folk receive a lower priority when it comes to accessing health services via their GP?

This would appear to be the case for both my parents (75 and 88 respectively) for whom the standard response seems to be "what do you expect, you're old" rather than any serious attempt to diagnose and address their concerns.

Is this another from of 'postcode rationing', is it legal and what research has been done to quantify if age is a factor in a GP's willingness to provide a diagnosis and recommend treatments? Any pointers, personal experience and advice appreciated.