By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. Soon after oral contraceptives were first introduced, more than 30 years ago, there were a number of reports of high blood pressure associated with their use. The pills contain a mixture of estrogens and progestins, but the amount of each ingredient in the preparations used today is only about one fifth of the original dose, although there is considerable variation between different brands. The Nurses’ Health Study has investigated the risk of developing high blood pressure from taking the oral contraceptives now in use. The study followed the health of more than 100,000 American nurses, who were first contacted in 1989. Among other questions, they were asked about their use of oral contraceptives and their blood pressure on three occasions over a four year period. Those who reported having hypertension at the beginning of the study were excluded from this analysis. The principal findings were: - The chances of developing hypertension were about 80% higher in the women who had used oral contraceptives in comparison with those who had not.
- The risk was slightly higher in women who had used them for more than six years. The risk did not vary significantly according to the amount of estrogens and progestins in the pills.
- Women with a family history of high blood pressure were at increased risk of developing it themselves, but they did not appear to be any more susceptible to the effects of oral contraceptives than those with no family history.
- There was no evidence of any racial difference in susceptibility to the effects of oral contraceptives on blood pressure; if anything, black women were at lower risk than white women.
- The number of women who were estimated to have developed hypertension as a result of taking the pills was small- the equivalent of 41 cases in 10,000 women over a period of one year, or 0.4%.
Doctor’s comments This study is reassuring for women taking oral contraceptives, because although there is a definite risk of developing high blood pressure, it is quite small. Furthermore, other studies have shown that if the pressure does go up, it will usually go back to its previous level within three months of stopping the pills. One implication is that if you are taking oral contraceptives, it is important to get your blood pressure checked at regular intervals. Women who already have hypertension are generally advised not to take oral contraceptives. Where it was published Chasan-Taber L and colleagues. Prospective study of oral contraceptives and hypertension among women in the United States. Circulation.1996;94:483-489. High blood pressure and bone weakening By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. There is a lot of evidence from both human and animal studies to show that high blood pressure leads to loss of calcium from the body, mainly as a result of increased amounts of calcium in the urine. Most of our calcium stores are in our bones, which leads to the question whether high blood pressure might contribute to the development of osteoporosis, a common cause of weak bones and fractures in older people, particularly women. A survey of 3,676 elderly white women living in four parts of the USA, whose average age was 73, had their blood pressures measured and also a bone density test, which was measured a second time after another three and a half years. Comparison of the bone densities over this period enabled the estimation of the rate of bone loss. The results showed that women with the highest blood pressures had nearly double the rate of bone loss in comparison with women with low blood pressure. Doctor’s comments Osteoporosis is a major health problem for older people and accounts for more than a million bone fractures a year in the US. It affects women more than men, and whites more than blacks (which is why this study did not include black women). The reason for the link with high blood pressure which this study shows is presumed to be the increased loss of calcium in the urine, which is a direct consequence of high blood pressure. A high salt diet also leads to more calcium loss. For people who have high blood pressure the good news is that thiazide diuretics (the sort normally used to treat high blood pressure in older people) actually reduce the calcium loss, and there is some evidence that they may help to prevent osteoporosis. Where it was published FP Cappuccio and colleagues. High blood pressure and bone-mineral loss in elderly white women: a prospective study. Lancet 1999;354:971. High Blood Pressure Isn't Well Controlled in Older Women Data from the Women's Health Initiative offers a glimpse of hypertension treatment in older women. Based on information from nearly 99,000 women aged 50 to 79, researchers found:
- 37.8% had high blood pressure (defined as 140/90 mmHg or being on medication for high blood pressure).
- While 64.3% of those were receiving medication, blood pressure was controlled in only 36.1%.
- More women on hormone replacement therapy were hypertensive than those not taking hormones.
- 44.3% of the hypertensive women used diuretics either alone or in combination with other classes of drugs.
- Women taking diuretics alone had better blood pressure control than those taking any of the other drugs by themselves.
The researchers, writing in the journal Hypertension, concluded that hypertension in older women is not being treated aggressively enough, especially not in those most at risk for stroke and heart disease because of their age. Source: Wassertheil-Smoller S, Anderson G, Psaty BM, et al. Hypertension and its treatment in postmenopausal women. Hypertension, 2000;36:780. (Abs.) Symptoms of High Blood Pressure
How do I know when my blood pressure is high? By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. For the most part, you can't tell if you have high blood pressure, and most hypertensive people have no symptoms. So the only way to find out if it's high is to have it measured. This statement may come as a surprise, because many people are convinced that they can tell when their pressure is high. It's certainly true that when you get angry or anxious you may feel yourself tensing up, and your heart pounding. You may even go red in the face, something that's often erroneously associated with high blood pressure. And you're right: your pressure is likely to be high at such times. But that's perfectly normal, and unless you spend your life being permanently angry, which fortunately most of us don't, it doesn't mean much. High blood pressure is of concern only when it's still high when you are not angry or tense. What are the symptoms of high blood pressure? By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. Usually, there are no specific symptoms which indicate that someone has high blood pressure. But some population surveys have shown that a wide variety of common symptoms, such as sleep disturbance, emotional upsets, and dry mouth, are slightly commoner in people with higher pressures. The differences are small, however. Going red in the face, or feeling flushed, is not indicative of high blood pressure. Headache and high blood pressure If you asked a hundred people what is the commonest symptom of high blood pressure, the chances are that the majority would say headache. In fact, not only do most people with high blood pressure not have headaches any more than the rest of us, but when they do, it's usually not from the blood pressure. Merely having a high level of blood pressure inside your head does not normally produce any symptoms; if you lift a heavy weight, your pressure may go up by 30 or 40 mm Hg, but you don't get a headache. What can cause headache is muscle tension. Any muscle that is tensed for long enough starts to hurt, and chronic tension in the scalp or neck muscles is a very common cause of headache. A study conducted many years ago shed some very interesting light on the relationship between headache and high blood pressure. Out of 104 people who had high blood pressure but were unaware of it, only three volunteered that they had headaches, although another 14 admitted it when asked. But of 96 people who had been told that they had high blood pressure, 71 said they had headaches. The simplest explanation for this finding is that being told that you have high blood pressure makes you start to worry, and that this in turn causes the headaches. There is a much smaller number of patients, mostly with very high pressures, in whom headaches are directly related to the height of the blood pressure. In such individuals treating the blood pressure will relieve the symptoms. Headaches & High Blood Pressure
Is Headache Related to Increases of Blood Pressure? By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. Headache is generally regarded as being a symptom of high blood pressure, although it is also stated that hypertension is the “silent killer”. Many people who have high blood pressure think that when they get a headache it means that their pressure has gone up. The problem here is that both headache and high blood pressure are very common, which means that it is certainly true that the two occur together, but what exactly is the connection? A study conducted in Poland has provided some interesting answers. One hundred and fifty patients, most of who were taking blood pressure-lowering medications, and who were referred to a hypertension clinic for evaluation, wore a 24-hour ambulatory blood pressure monitor. These monitors take a blood pressure reading every 20 minutes during the day, and 30 minutes during the night. The patients were asked to record in a diary whenever they had a headache, and in fact during the 24-hour monitoring period 43 of the patients (about one third) reported a headache, which lasted an average duration of 3 hours. In general, there was no connection between the occurrence of headaches and what was happening to the blood pressure, and in most cases the highest readings of blood pressure were not associated with headaches. In addition, there was no particular tendency for the blood pressure to go up or down just before the headache started. Whether or not the patients were taking blood pressure lowering medications also had no effect on the association between headache and blood pressure. Doctor’s comments Most of us, whatever our blood pressure levels, get headaches from time to time, and the relationships between blood pressure and headache have always been a bit uncertain. It is true that in a small number of patients with very high blood pressure, headache can occur as a consequence, but this is probably rare. One study actually found that headaches were more likely to occur after people had been diagnosed with high blood pressure, which may have been because of the anxiety associated with the awareness of high blood pressure, rather than because of the blood pressure itself. The clear finding of this study is that most of the headaches in people with high blood pressure, whether treated or not, do not occur because the blood pressure has gone up There is some evidence from other studies that people with hypertension are more likely to have migraine headaches, and also some reports that some of the blood pressure lowering drugs such as calcium channel blockers and beta-blockers are effective for treating these. Again, this may not necessarily a result of a lower blood pressure. The message here is that if you have hypertension and are getting headaches, it does not mean that your blood pressure out of control, and that the best treatment for the headache may be the traditional pain killers such as aspirin. Where it was published P Kruszewski and colleagues. Headache in patients with mild to moderate hypertension is generally not associated with simultaneous blood pressure elevation. Journal of Human Hypertension, 2000; 18:437.
Study Proves Headaches Are Not Related to Blood Pressure Many people with high blood pressure believe there is an association between headaches and their pressure levels. There has been little direct evidence to support the relationship, and doctors repeatedly advise their patients that there are no symptoms of high blood pressure. Now a new study using ambulatory blood pressure monitoring has provided convincing data to back up the lack of any connection. Seventy-five people with mild hypertension had their blood pressure monitored for 24 hours and kept a log of their headaches. One-third of the study participants had a headache while they were being monitored, but there was no difference in their blood pressure curves from those of the people who did not have a headache. Blood pressure values registered during the headache and in the hours before and after it were not different from each other. Even in a subset of 8 patients who had a migraine, the analysis showed a similar pattern. This report underscores doctors' advice not to rely on the occurrence of a headache as a sign that your blood pressure is up and the importance of following your treatment program and taking medication as directed all of the time. Source: Gus M, Fuchs FD, Pimentel M, et al. Behavior of ambulatory blood pressure surrounding episodes of headache in mildly hypertensive patients. Archives of Internal Medicine (Jan.) 2001;161:252-255. (Abs) Measuring High Blood Pressure What are Korotkoff sounds? The 'Korotkoff sounds' are the sounds that a doctor or nurse listens for when they are taking your blood pressure. They are named after Dr. Nikolai Korotkoff, a Russian physician who described them in 1905, when he was working at the Imperial Medical Academy in St. Petersburg. They are detected by listening with a stethoscope placed over the brachial (arm) artery just below a blood pressure cuff, as it is gradually deflated from a pressure high enough to occlude the artery and stop the blood flowing. As the cuff pressure reaches systolic pressure, the blood starts to flow, and a whooshing sound is heard (the first phase of the Korotkoff sounds). As the cuff is deflated further, the artery opens and closes, and the flow of blood is turbulent, so sounds are still heard. When the cuff pressure is less than the diastolic pressure, the artery is open all the time, and the flow of blood is smooth, and the sounds disappear. Systolic pressure is registered as the pressure at which the sounds are first heard, and diastolic as the pressure at which they disappear (phase 5 of the Korotkoff sounds). What is an electrocardiogram? This test is used routinely in the evaluation of people with high blood pressure and is the traditional way of seeing if the hypertension has had any affect on the heart. When heart muscle contracts, it creates an electrical impulse, which can be detected on the surface of the body. The electrocardiogram (ECG or EKG) is performed by applying six electrodes to the skin on different parts of the chest. Another four are applied to each wrist and ankle. These pick up the electrical signal coming from the heart, which is amplified and written out on a paper strip. Each electrode looks at the heart from a different viewpoint, and the electrical waveform is slightly different in each one. The pattern of waveforms in the different leads provides a lot of information about the structure and function of the heart. For the evaluation of high blood pressure, the two most important things are whether the heart is enlarged, and whether there's any sign of damage from a heart attack.
Do You Have 'White Coat Hypertension'? Some patients have what is called 'white-coat hypertension;' their blood pressure is consistently elevated in the doctor's office or clinic but normal at other times. It is called this because the patient is reacting to the white coat that the doctor or other caregiver is wearing. If your blood pressure is high when measured at the doctor's office or clinic but is low when you measure it yourself, you should mention that to your doctor so that a more thorough evaluation may be done. Sometimes in these cases ambulatory blood pressure (ABP) monitoring will be used to further measure blood pressure. These devices take readings every 15 to 30 minutes throughout the day and night while you go about your normal daily activities. An analysis of these readings will clarify the status of your blood pressure. Source: The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. NHLBI, November 1997. Stress & High Blood Pressure
Panic attacks are more common in people with high blood pressure By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York. Panic attacks have only been recognized as a discrete entity since 1980, and it has been suggested that they may be related to hypertension. Now a study has come up with an answer. The definition of a panic attack is “ a discrete period of intense fear or discomfort involving at least four of the following symptoms: - Shortness of breath or smothering symptoms
- Dizziness, unsteadiness or faintness
- Palpitations or rapid heart beats
- Trembling or shaking
- Sweating
- Choking
- Nausea or stomach upset
- Depersonalization or feeling of unreality
- Numbness or tingling
- Hot flushes or chills
- Chest pin or discomfort
- Fear of dying
- Fear of going crazy or losing control
The study looked at two samples of patients with high blood pressure (all were taking blood pressure lowering medications or had a blood pressure of at least 160/90mmHg), one of which was selected from a primary care practice, and the other from a hospital clinic, and compared them with the same number (about 350 people) of patients with normal pressure from the same family practice. All were sent questionnaires asking them if they had the symptoms described above. The main finding was that panic attacks were significantly commoner in people with hypertension as opposed to those with a normal blood pressure: the percentages of people with panic attacks were 35% in the primary care practice, 39% in the hospital practice, and 22% in the normotensives. Both groups of hypertensives were more likely to have spontaneous panic attacks (ones that started for no obvious reason), and the attacks were more likely to be severe. The hypertensives were also more likely to report that they were generally anxious than the normotensives. The use of different types of antihypertensive drugs did not appear to influence whether or not the hypertensives had panic attacks. In most patients the panic attacks started after the hypertension. Whether hypertensive or not, women were more likely to report panic attacks than men. Doctor’s comments This study shows clearly that there is a connection between panic attacks and hypertension, but it does not tell us which is the chicken and which is the egg. The fact that the hypertension started before the attacks in most patients makes it unlikely that the attacks were the direct cause of the hypertension, however. Other studies have shown that blood pressure goes up during an attack, but it comes down again when the attack is over. What causes these attacks remains a mystery; although they have some relation with a generally anxious personality, this relationship is not very strong. Where it was published SJC Davies and colleagues. Association of panic disorder and panic attacks with hypertension. American Journal of Medicine 1999; 107:310 Does stress cause hypertension? There is no doubt that acute stress can cause a transient increase of pressure, but whether exposure to chronic stress raises pressure is controversial. When people move from a traditional village life to the big cities, their blood pressure goes up, but whether this is from stress or a change of diet is uncertain. Having a stressful job may raise the pressure in men but probably not so much in women. Fight or flight' response raises blood pressure -- even while you're asleep Many people experience sleep apnea; it occurs especially in those sleeping on their backs and snoring, when the tongue and soft parts of the upper airway may fall back and partially block the airway. This causes a period of intermittent breathing known as obstructive sleep apnea (OSA). From the University of Colorado Health Sciences Center comes a report on the effect of sleep apnea on hypertension. As the period between breaths increases, the amount of oxygen in the blood may fall. This sets off the body's 'fight or flight' mechanism, which is a reflex controlled by the sympathetic nervous system. When that happens, the vascular system clamps down and raises blood pressure in an attempt to get the body ready for action. When normal breathing resumes, blood pressure levels return to normal. Hypertension in awake patients is also associated with increased activity of the sympathetic nervous system. Individuals who have not been identified as OSA patients exhibit this same sympathetic response. A common respiratory therapy, called continuous positive airway pressure, or CPAP, has been shown to lower blood pressure in some hypertensive OSA patients. Effective CPAP therapy moderates this hypertensive effect even in awake patients with undiagnosed OSA. Source: Zwillich, CW. Obstructive sleep apnea causes transient and sustained systemic hypertension. Int J Clin Pract 1999;53(June):301-5. (Abs) |
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