What are some potential causes of high systolic blood pressure?

November 19, 2012 7:10 PM

I would like to figure out why my systolic blood pressure is high, but my diastolic is usually normal. What avenues are there for me to begin looking into?

I am a 29 year old male, 5'10" and 170 lbs. I lowered my resting blood pressure from ~140/88 two years ago to ~124/82 one year ago with exercise, diet, CoQ-10 and garlic. My diastolic number has remained good and even has improved in the last year, but the systolic number has begun creeping up again and I want to figure out why.

My diastolic blood pressure is usually in the 70s mmHg and virtually never in the hypertensive range. My systolic blood pressure varies wildly - in the morning it's usually in the low to mid 120s. In the day or evening, my first reading upon sitting could be anywhere from mid-upper 120s to occasionally 150s. 160 if I'm at the doc's, which always makes me nervous. It'll generally settle for half the difference between 120 and the first reading if I wait a few minutes and take a couple more readings.

I know "lower salt intake" is a common recommendation, and I understand this is due to the fact that some people retain more water in response to this, which raises blood pressure. I'm interested in more things one can try for lowering systolic blood pressure, but moreso in the reasons behind them.

I'm not asking for a diagnosis, but I would like to know more about the potential causes for this condition to look into with my doctor. All he can currently suggest, besides potentially medicating, is to suggest eating low-salt (which I tend to do anyways - I eat "primal" / loose paleo) and getting aerobic exercise (I have recently started adding cardio to my lifting routine). Thanks.

My basic blood panel is very good except for elevated LDL and TSH (T3, T4, rev T3 are perfect).

posted by Earl the Polliwog to health & fitness (4 answers total)

"Essential hypertension", that is, hypertension without a known cause, is the diagnosis for 95% of patients with hypertension. Unfortunately, that means that physicians don't know why most people develop hypertension, and typically, if lifestyle changes fail (meaning low sodium diet and exercise), then it is presumed to be what we call "idiopathic" (meaning we don't understand why it happened) or genetic or a combination of both. There are a few other suggestions for lifestyle modifications, like increasing intake of vitamin D, potassium, calcium, and cutting alcohol intake. As you noted, only certain people are 'salt-sensitive' for complicated physiologic reasons. The problem is, there's a pretty large proportion of people who really can't bring down their BP with lifestyle alone and need medications to treat it.

Here's also a blurb on isolated systolic hypertension - it's more common amongst the elderly. This uses a good deal of technical jargon, apologies. I don't think it's going to tell you much except that unless there is a specific underlying cause for the hypertension, like your thyroid, which you mentioned has already been ruled out (I'm assuming your doctor already did the usual screening tests for other, rare causes of secondary hypertension), and lifestyle changes aren't solving the problem, your other recourse is medication...
IANYD/This is not medical advice.... Hope that is helpful.
posted by treehorn+bunny at 8:41 PM on November 19, 2012 [3 favorites]

Take your blood pressure after waking--sit for 5 minutes before doing it. If it is "normal" ( not perfect what ever that is) then stop taking it all the time. Blood pressure fluctuates dramatically through out the day--particularly if you have not calmly sat for at least 5 minutes. Take your blood pressure at the same time, under the same conditions, and look for systematic changes--not day to day variations. I would look for repeated readings in the 110-120(systolic) range and 70-80. Good luck--Exercise regularly, watch your weight and look for consistent long term changes.
posted by rmhsinc at 6:09 AM on November 20, 2012

About one half of patients who have essential hypertension have sleep apnea. Sometimes when a person has high blood pressure that is resistant to treatment, the cause is an undiagnosed sleep disorder.

The stereotype of sleep apnea is a fat middle-aged man who snores heavily. Not all apneics fit this profile - some are thin, some are premenopausal women. Does your bed partner(s) say you snore or stop breathing during the night? Do your bed partners kick or elbow you a lot to get you to stop that racket or start breathing again? Do you wake yourself up with a jolt and a snort, or a choking or gagging feeling? Do you ever dream of drowning or choking? Do you get up to pee more than once even if you haven't had lots of liquids or coffee? Do you feel hot and sweat heavily when you sleep even if your room is cool? Is your sleep unrefreshing no matter how long you stay in bed, do you always spend your mornings in a foggy haze?

Ask your doctor for a sleep test just in case. If you don't have sleep apnea - no harm done. If you do, then treating your apnea just might help your blood pressure levels.
posted by Rosie M. Banks at 6:46 AM on November 20, 2012

My doc has not in fact ruled out all of the potential secondary causes in that one link - that may be helpful, thank you. I very much appreciate the technical, detailed language in your responses and links.

My doc "ruled out" apnea because I don't generally snore, but I do on occasion wake up with my heart pounding a bit. I will look into that further.
posted by Earl the Polliwog at 8:48 AM on November 20, 2012