First of all, ASK the doctor. Now that that is said, when the lower number goes over 90 it is classified as high blood pressure
. The top number is not really that significant at this point. The bottom number is the constant pressure in the system when the heart is at rest and this is why it is the more serious of the two.
At, 110 mmhg, your Mom could have some serious problems, yes. Is she in immediate danger, no one can tell you that. If they could they would be Jesus. There is no way to know when exactly something will happen. How ever the odds are greater that things like a stroke
The best thing is to have her seek a doctor to treat the high blood pressure.