HEALTHNET

Stroke - a silent killer? (Part 1)

Is stroke really a silent killer that may occur on everyone around you and me?

(Posted on 19 April 2007)

One day after work I saw a familiar face sitting on a wheelchair in the lift. Later I was told that he suddenly developed a stroke a few weeks before. He lost the ability to work and it takes time to recover. Is stroke really a silent killer that may occur on everyone around you and me?

'Strokes' in medical terms

In medical terms, stroke is a syndrome and the major manifestation of cerebrovascular disease (CVD), which is a board term describing disorders that affect the blood vessels of the central nervous system. Stroke is subdivided into two major subclasses, namely hemorrhage stoke (20%) and ischemic stroke (80%). According to statistics announced by Department of Health, CVD is the forth leading cause of death in HK at 2005 and 87% of such cases happened on elderly aged over 55.

Impacts and symptoms of strokes

Hemorrhage stroke describes the situation when blood is leaked from the blood vessel and penetrated into the neighboring tissue. Direct contact of blood with the brain cell results in damage to the tissue and presents as symptoms in stoke. For ischemic stroke, blood flow is limited and thus not capable to reach certain area of the brain tissue. Insufficient delivery of oxygen and nutrients to those tissues results in degeneration and damage. Depends on the region affected, different symptoms may be seen in stoke patient. For example, if the damage is only localized in a small part of the brain like visual center, it would only produce localized defect to the patient's visual ability like double vision or blindness. On the other hand if regions affected is large, generalized deficits occur which may affect neurons, motor control and hemiplegia etc. Such deficits are usually partially reversible or even irreversible and thus prevention of stroke is sounded more effective and valuable.

Source: Hong Kong and Drug Education Resources Centre, The Society of Hospital Pharmacists of Hong Kong