Hypertension or high blood pressure has grown in epidemic proportion around the world. It is affecting not only individuals from affluent western countries, but also those living in third world developing countries. Urban life styles, obesity, lack of exercise, stress, use of alcohol and tobacco are said to be the risk factors causing high blood pressure. Genetic susceptibility is also present. A person having a sibling or parent or a blood relative with hypertension is more likely to develop it. Recent studies have pointed out that even under nutrition can cause chronic cardiovascular diseases including hypertension.
Rise in catecholamine (adrenaline and non noradrenaline) levels causes narrowing of blood vessels and increase in the blood pressure. Hypertension affects the eyes, kidneys as well as the nervous system.
In case of very high blood pressure(>180 or 200 mm. Hg) the blood vessels of the brain are burst resulting in damage to some part of the brain. This results in sudden paralysis of one side of face and or body, visual disturbances, loss of speech, loss of consciousness e.t.c. neurological problems depending on part of brain affected. The sudden bleeding due to rupture of blood vessels causes compression of brain substance and swelling. This can result in coma or disorientation and or convulsions. Sudden bleeding in the brain substance due to rupture of one or more major blood vessels is usually fatal. The blood vessels of the brain can develop total blockade due to stiffening of inner linings of blood vessels, causing paralysis of one side of body and or face. High blood pressure also contributes to it. Timely treatment can save the person’s life and stabilize him Medicines and physiotherapy form part of the treatment. Recovery usually takes 6 weeks to 6 months or longer depending on blood vessel/vessels affected and state of surrounding blood vessels.
Long standing high blood pressure damages blood vessels of the body including brain. This affects the blood supply of the body parts and brain. Damage to the tissues in deep interior of the brain substance does not manifest dramatically as a stroke, i.e. sudden paralysis or neurological disturbances, among others. But subtle behavioral changes occur in the individual. These include loss of memory, disorientation to time, space and or person, loss of basic social behavior, lack of personal hygiene, e.t.c. The se are usually presumed to be related to aging process. But underlying cause is uncontrolled high blood pressure. Senile dementia, i.e. behavioural changes with aging is induced and aggravated by uncontrolled hypertension.
All these conditions can be diagnosed by scans of the brain and timely treatment is useful.
Studies have shown that those people having diabetes with hypertension are more likely to develop damage to the peripheral nerves, ( nerves that carry sensations from outside of body to the brain) as compared to those who have diabetes alone. This manifests as tingling, numbness or loss of sensation in limbs.
Long standing high blood pressure damages the kidney causing kidney failure. This reduces the elimination of toxic waste products from the body, which accumulate in the body and also affect the brain after reaching there via the blood stream. Electrolyte imbalance caused due to kidney failure causes muscle cramps , weakness and also affects functioning of the brain. Thus the individual suffers from disorientation and or altered consciousness and even coma.
Considering these harmful effects of high blood pressure on the brain, it is imperative that a person avoids developing it. If he or she has high blood pressure it is advisable to keep it controlled with dietary measures, regular exercise, adequate relaxation and regular intake of prescribed medicines.
Dr Rachna Pande, Specialist, internal medicine