What Causes Slurred Speech?

Thank you. I ve been experiencing increasing speech difficulties for 4-5 months. Started very minorly but has increased to slurring and difficulty enunciating certain words, as well as a definite slowing of cadence. Becomes more pronounced later in the day. Have had an MRI and MRA with no evidence of TIA or other circulatory or brain problems. I do, however have an increase in LDL, although all other blood tests revealed nothing unusual. I am now taking vitamins and supplements, such as coQ10 and fish oil. I have various neurology appointments scheduled (in numerous locations to try a get one as soon as possible) but they are many months off (!). My father died of Parkinson s about 20 years ago and had speech problems early on, so I am very concerned about that possibility. Finally got in to see a Speech Pathologist this Monday.