Our blood pressure is not a fixed number. It fluctuates throughout the day, influenced by our emotions, activities, and even dietary consumption. It may rise after physical activities, or after a few cups of coffee, or by stressful events. In those situations, your blood pressure readings will show a relatively higher number, which means you have high blood pressure at the moment.
But hypertension, on the other hand, is a chronic high blood pressure. It occurs when your blood pressure stays high for a long period of time, regardless of what you eat or do. You may feel healthy but in reality, your elevated blood pressure is damaging your body. If left untreated, your high blood pressure can lead to serious problems such as stroke and heart disease.
How do I know that I have hypertension?
Blood pressure readings are represented by two figures. The top number represents the systolic blood pressure; the measurement of blood pressure in the vessels when your heart beats. The bottom number is called the diastolic blood pressure; the measurement of blood pressure in the vessels during the rest of the heart between beats. According to WHO (2013), hypertension was defined as a systolic BP equal to or above 140 mmHg and/ or diastolic BP equal to or above 90 mmHg.
Differentiating causes and risk factors
A small number of high blood pressure cases are secondary hypertension — high blood pressure that's caused by another medical condition that was present first. This includes pregnancy-induced hypertension (PIH), certain heart defects, and kidney disorders. Most often, if the condition causing the high blood pressure can be resolved, the individual's blood pressure will normalize as well.
However, 95% of people with high blood pressure suffer from primary hypertension; high blood pressure that has no identifiable cause. In these instances, many risk factors have been linked to this disease. The term "risk factor" indicates any attribute, characteristic or exposure of an individual that is associated with an increased likelihood of developing the disease but not necessarily a cause. This hereby implies that the more risk factors for hypertension that you have, the greater your chance of getting the disease.
Risk factors for hypertension
Some risk factors are categorized as non-modifiable, in which you can't change. However, many non-modifiable risk factors can be controlled and their effect
reduced by making changes to your lifestyle. The other risk factors are called modifiable because you can do something about.
Common hereditary and physical risk factors for high blood pressure include:
- Family history - If your parents or other close blood relatives have high blood pressure, there's an increased chance that you'll get it, too.
- Age - As we age, our blood vessels gradually lose some of their elastic quality, which can contribute to increased blood pressure. Hence, the older you are, the more likely you are to get a high blood pressure. However, children can also develop high blood pressure.
- Gender - Until age 64, men are more likely to get high blood pressure than women are. At 65 and older, women are more likely to get high blood pressure.
The effect of these modifiable risk factors can be reduced through lifestyle changes.
- Obesity and overweight - Overweight status is defined as body mass index (BMI) 25-29.9 kg/m2 while obesity is defined as BMI ≥ 30 kg/m2. The more you weigh, the more blood flow is needed to supply oxygen and nutrients to your tissues. As the volume of blood circulated through your blood vessels increases, so does the pressure inside your arteries. This puts an extra strain on your heart and circulatory system that can cause serious health problems.
- Little or no physical activity - When you don't move much, you usually have a higher heart rate, which makes your heart pump harder with each heartbeat. But when you exercise, your body makes hormones that relax your blood vessels and lower your blood pressure. Exercise increases blood flow through all arteries of the body, which leads to the release of natural hormones and cytokines that relax blood vessels, which in turn lowers blood pressure. Lack of physical activity also increases the risk of being overweight.
- Dietary factors. - A diet that is too high in sodium and too low in potassium puts you at risk for high blood pressure. Sodium, an element in table salt, can boost your blood pressure because it plays a role in narrowing your blood vessels and makes your body retain more fluid. Both factors increase blood pressure. Adequate potassium is needed to balance your sodium levels and keep your blood pressure in check as it causes the smooth muscle cells in your arteries to relax, which lowers blood pressure.
- Cigarette smoking - Smoking can temporarily increase your blood pressure while prolongation of this habit will increase the risk of hypertension. In addition to that, chemicals in tobacco damage your blood vessels, which narrow them and lead to higher blood pressure. Secondhand smoke and use of other tobacco product also increase the risk of hypertension.
- Alcohol intake - Having more than two drinks per day can cause hypertension, activating your adrenergic nervous system, causing constriction of blood vessels and a simultaneous increase in blood flow and heart rate. Light-to-moderate alcohol use associated with increased risk of hypertension in men but not women. Meanwhile, heavy alcohol use (averaging > 2 drinks/day) associated with increased risk of hypertension in women.
- Stress - High levels of stress can lead to a temporary, but dramatic, increase in blood pressure. Although it's still debatable whether stress directly relates to hypertension, chronic stress undoubtedly encourage behaviors that increase blood pressure. Some examples are poor diet, physical inactivity, and using tobacco or drinking alcohol more than usual.
- Medication - Some Non Steroidal Anti-inflammatory Drugs (NSAIDs) medication like Ibuprofen may cause worsening of existing hypertension or development of new high blood pressure. Likewise, cough and cold medications frequently contain decongestants such as pseudoephedrine and phenylephrine. These medications cause your blood pressure and heart rate to rise, by constricting all your arteries, not just those in your nose. There is also a reported increased risk of hypertension by insulin use.
- Overlying disease - Obstructive sleep apnea may increase the risk of developing hypertension and is common in people with resistant hypertension. Some health problems including prehypertension and diabetes can also be the risk factors for high blood pressure. Most people with diabetes also develop hypertension.