Paralytic stroke is a fairly common problem in the elderly population. Its mortality is low but it leaves devastating effects on the afflicted person, who becomes a dependent person for the rest of his life.
The prevalence of stroke according to a study in the journal of ICMR has been estimated to range from 44.29 to 559/ 100,000 in different parts of India. These numbers could be an underestimation for want of good prevalence studies.
There are ways to estimate the chance of getting a stroke by using stroke risk calculators. A few of them are the webpage of American Heart association or Med India stroke risk calculator.
These take into consideration age and the risk factors of stroke. An annual risk of more than 10% is concerning and should prompt a visit to a doctor to take a medical opinion.
Risk Factors of Stroke
High Blood Pressure (Hypertension): This is the most important risk factor both for ischemic ( due to clotting of the culprit artery supplying the brain) or haemorrhagic (because of bleeding inside the brain) stroke. Controlling it and keeping it below 130/80 mms Hg considerably reduces the risk of having a stroke.
Smoking: It is an important and a preventable risk factor. Both active and passive (second hand) smoking is bad. It also has a linear relationship with the number of cigarettes smoked.
Truncal Obesity: Waist circumference (WC) is a simple measure of truncal obesity. WC cut off points of 102 cm in men and 88 women as per the international norms seems to be high for South Asians. The recommended values for Indians are 78 cms for men and 72 cms for women.
Lack of Exercise and Poor intake of fruits and vegetables: Lifestyle plays an important role as a risk factor. Individuals who are physically inactive, sedentary and consume a diet inadequate in fruits, salads and vegetables are more prone to getting a stroke.
High lipid levels: High levels of bad cholesterol (LDLc) and associated lipo-proteins are also an important risk factor. This is also a correctable cause and needs both dietary and aggressive pharmacotherapy with statins and additional drugs whenever needed. In very high-risk patients with multiple risk factors or a previous stroke levels < 55 are recommended.
Type 2 Diabetes Mellitus: This again adds to the risk especially in ischemic strokes. The relationship is however weaker as compared to heart attacks. Early recognition and treating it properly is important.
Psycho-Social Factors: Stress at home and stress at work, anxiety and depressive states all have been shown to be directly and causally related.
Cardiac Causes: Strokes can occur following a heart attack, usually because of a clot formed at the site of muscle damage. In patients with enlarged ventricles also formation of blood clots can occur which can get dislodged and go to the brain artery producing an embolic stroke.
Atrial Fibrillation (AF): An important cardiac cause is a disorder of heart rhythm called atrial fibrillation. This is a chaotic beating of the upper portion of the heart called the atria.
The commonest age of acquiring this arrhythmia is after 65 years, and its incidence goes on increasing with age and after 80 years it can be present in more than 10 % of the population. These patients usually have normal heart valves and are also called “non-valvular” atrial fibrillation.
Children and young adults with narrowing of the mitral valve (Mitral Stenosis) because of rheumatic fever (fever and joint inflammation) in childhood can get rheumatic heart disease and mitral stenosis with or without a leaking valve. This disorder can be permanent or transient or paroxysmal. (Coming off and on).
The risk of occurrence of stroke in non-valvular AF can be calculated using a score based upon age, sex, history of heart failure, hypertension, diabetes, previous heart attack or disease of limb arteries and a previous stroke. Any body in AF having a score more than 1 is at a high risk for stroke. Orally administered anti coagulants are very effective in preventing a stroke in moderate or high-risk individuals.
Preventive strategies: It is recommended that every senior citizen should assess his/her stroke risk. Not to smoke, engage in physical exercise, keep BP below at least 140/90 mms Hg, optimise body weight, use statins in case of high cholesterol levels. Those with irregular pulse or palpitations get an electrocardiogram done for diagnosis of AF. If present even for short periods see a physician and take long term blood thinners (anti-coagulants) for long term under supervision.
Take Home Message:
The chance of getting a stroke increases as we age. They can be fatal but even if they are not these can result in a serious life long disability.
Over the years we have known a lot about the risk factors leading to a stroke. A number of measures can be taken to minimise this risk.
Healthy lifestyle, watching weight and recognizing these common risk factors and managing them effectively with medical consultations can go a long way to maintain a stroke free elderly life.
Prof Upendra Kaul, Founder Director, Gauri Kaul Foundation
