Blood pressure: The good and bad of the highs and lows
BY BARB FABER, APNP
Ministry Medical Group
People on blood pressure medication often record readings with a home monitor and in most cases the results show frequent fluctuations but few surprises.
When blood pressure is higher than usual, it is usually because salty foods have been eaten. When it goes too low, it could be because of not drinking enough water to make up for fluids lost because of diuretic medication.
If there are some wider than normal fluctuations with no ready explanation, that can be a cause for concern and your primary care clinician or specialist can order some heart tests to provide valuable insight into the situation.
Blood pressure represents the force that blood exerts against the walls of blood vessels as it is pumped by the heart muscle. Your blood pressure should be 120/80 mm/Hg or lower; hypertension is defined as any reading of 140/90 or higher.
It’s normal, of course, for a person’s blood pressure to rise and fall from minute to minute with changes in posture, exercise, stress or sleep. As a result, health care professionals consider an average reading more important than that at any one time.
A study published in the Annals of Internal Medicine [July, 2015], however, found such fluctuations associated with an increased risk of heart disease and premature death.
The study involved nearly 26,000 people taking medicine for hypertension. Subjects experiencing a blood pressure variation of about 15 points had a 46-percent increased risk of a stroke and a 30-percent higher risk of a heart attack or heart-related death compared to those whose blood pressure remained stable. For this type of study, no cause/effect relationship can be established.
Further studies are needed to determine what patients can do, if anything, to protect themselves. Diuretics and calcium channel blockers are generally associated with fewer variations in blood pressure, but there is no proof at this time that a change to these types of medication would be beneficial in preventing fluctuations.
There are many reasons for a short-term increase, but most of these are smaller.
SALT: People who are salt sensitive will retain fluid after eating a very salty meal, resulting in a short-term weight gain and a rise in blood pressure. Persons with hypertension are advised to restrict their sodium intake, and many are prescribed diuretic medications to help establish fluid balance.
STRESS: If you are stressed, emotionally or physically, your breathing gets quicker and deeper, your heart beats faster and your arteries constrict, making the heart work harder to pump blood throughout the body. The result is higher blood pressure. Everyone experiences occasional stress, but if you feel you are almost constantly battling stress, you might benefit from relaxation or stress reduction therapy.
CAFFEINE: Caffeine is a stimulant, designed to get your system revved up. One cup probably won’t affect your blood pressure; three or four cups might. If you have a home blood pressure monitor, take a reading before and after drinking coffee or tea, and see what happens. If you see a significant increase, then maybe you should cut back on your caffeine.
MEDICATIONS: Some medications and supplements can increase your blood pressure or interfere with your blood pressure medications. NSAIDs (nonsteroidal anti-inflammatory drugs) such as ibuprofen and naproxen can cause you to retain fluids and, as a result, contribute to high blood pressure. Decongestants and acetaminophen can also have a negative effect.
CALCIUM/CHOLESTEROL DEPOSITS: Probably the most common reason for hypertension. When arteries are narrowed or clogged, the heart must pump harder to get good circulation. High blood pressure and high cholesterol often go hand-in-hand.
All of the above can cause blood pressure to go up; dehydration can cause it to go down. What’s important is how high the blood pressure goes and how long it stays there.
The recent study suggests that you should be vigilant about following your blood pressure plan–including medication, diet and exercise. And take frequent readings, noting any wide fluctuations from day to day or week to week. If you have been eating too many salty foods or taking some supplements on the restricted list, it’s time to change your ways.
If the wide fluctuations continue, talk to your primary care clinician right away.
Barb Faber, APNP is a Nurse Practitioner with Ministry Medical Group, part of Ascension