Chronic acid reflux can cause throat irritation and eventually affects the vocal chords. Lots of Phlemn [spelling?].
Or perhaps she is on a medication that magnifies congestion? Some drugs for incontinence will do that.
Hard to know. The problem with Ms Hillary, however, is with her mind and her ideas.
My guess is congestive heart failure. Fluid in lungs, takes diuretics to rid water. Swollen ankles, hands. Explains why she has to run off stage to urinate during debate as well