Blood pressure and heart rate

Hi -- my dad is experiencing high heart rate i.e. 101 and low blood pressure i.e. 105/69 in the morning and a low heart rate i.e. 72 and high blood pressure i.e. 150/90 at night.   Any idea why the variation in blood pressure and heart rate at these different times in the day?  He is about 75 years old.  Thanks.

[Jerry_NJ]

I think only a doctor can give you a meaningful answer.  But, the only numbers that give me some concern are the 150/90 BP at night.  If this pressure is maintained for several hours at a time, I'd think treatment to lower the BP should be discussed with his doctor. I don't consider 72 a low HR, I think it is about normal for someone 75, looks like a good rate to me, whish I had it myself.