Hypertension – high blood pressure (BP)
AS WE LEARNED previously, high blood pressure is a modifiable risk factor for cardiovascular disease and is expressed as two figures, for example 150/80mmHg (150 over 80). The higher figure is the SYSTOLIC pressure produced when the heart contracts and the lower figure is the DIASTOLIC pressure in the arteries when the heart rests between beats. Blood pressures change during the day and with various activities, but a constantly raised figure would require intervention.
BP of 160/100 or more is definitely high and would require treatment.
BP of between 140/90 and 159/99 is considered moderately high and wouldn???t normally be treated UNLESS other risk factors are present, such as Diabetes, Cardiovascular Disease, Heart or Kidney Disease
BP of between 130/80 and 139/89 is generally fine for most people, but would require lowering IF there are; Kidney problems associated with Diabetes; history of Heart Attack, Stroke or chronic Kidney Disease.
In most cases, the cause of raised blood pressure is not known and is called ESSENTIAL hypertension. It becomes more common in later life and may be due to the narrowing of the arteries. In a small number of individuals, raised BP is caused by other conditions such as kidney or hormone problems and is then known as SECONDARY hypertension.
Generally a BP of below 140/90 is the goal; however, even lower pressures are advisable in patients with Diabetes, Kidney Disease or Cardiovascular Disease.
There are a number of lifestyle modifications that can help reduced BP, these include:
* Lose weight (if overweight)
* Eat a healthy diet
* Regular exercise
* Reduce salt intake (no more than 5-6g per day)
* Reduce caffeine intake (no more than 5 caffeine drinks per day)
* Drink alcohol moderately within current guidelines
If lifestyle measures fail to reduce BP sufficiently, there are a number of drugs that can help lower BP: the choice depends on several factors and in most cases will require a combination of drugs to achieve the desired result. There are five main groups:
Ace inhibitors e.g. Captopril, lisinopril, perindopril – particularly helpful in patients with Diabetes or Heart Failure – can cause an irritating cough.
Angiotensin receptor blockers, e.g. Candersartan; Losartan. Similar to ace inhibitors, but without the troublesome cough.
Beta blockers e.g. Propranolol, Atenolol, Bisoprolol. Can cause cold hands and feet; impotence; sleep disturbances and tiredness. Should be avoided with asthma or lung disease. Often used for other conditions such as angina.
Calcium channel blockers, e.g. Nifedipine, Amlodipine, Diltiazem: can cause swollen ankles; headach; flushing; constipation and dizziness. Also used to treat Angina.
Thiazide diuretics (water tablets) e.g. Bendroflumethiazide: Can cause gout and increase cholesterol levels. Impotence can develop in some patients and can cause potassium loss.
Other anti-hypertensive drugs include methyldopa and alpha blockers, e.g. Doxazosin
Generally, if you are aged under 55 and are NOT of black African or Caribbean origin, first choice treatment will be with an Ace inhibitor or Angiotensin receptor blocker. For over 55’s and those of black African and Caribbean origin then first choice treatment is with a calcium channel blocker or diuretic.
Written by Michael Lord