I'm 44 and in the last year I have noticed my heart rate picking up when i wake in the middle of the night. Not really when i wake in the morning. it only lasts for seconfs but it is frightening as hell. Also been getting dizzy spells once in awhile after sitting for long periods of time. I gained weight over the last 10 years after my child and have noticed my blood pressure increasing. 132/90 last visit. i go to the gym regularly and have no problems during exercise. Not taking any drugs besides my ritalin. Had been on it for years and changed to Adderall for a period then went back to ritalin. Could it be doing this?