Atherosclerosis

Atherosclerosis is the gradual build-up of cholesterol-rich plaques in the walls of arteries, making them narrower and stiffer. It's the underlying cause of most heart attacks, strokes, and peripheral artery disease. Atherosclerosis develops slowly over years — often silently — and then causes sudden events when a plaque ruptures and triggers a clot. In Indians, atherosclerosis often starts younger and causes disease at lower BMIs than in Western populations.

How it develops

• Damage to the inner lining of arteries — from high blood pressure, smoking, high cholesterol, diabetes, or inflammation
• Cholesterol (particularly LDL) and immune cells accumulate in the damaged area
• Over years, a plaque forms — a mix of cholesterol, cells, and calcium
• Plaques narrow the artery; stable plaques reduce blood flow gradually
• A plaque can rupture — exposing content that triggers a blood clot, suddenly blocking the artery. This is how heart attacks and most strokes happen.

What it causes

• Heart attack
• Angina (chest pain with exertion)
• Stroke
• Peripheral artery disease (leg artery narrowing)
• Chronic kidney disease (from renal artery narrowing)
• Intestinal ischaemia (rare)
• Erectile dysfunction (often an early sign)
• Aortic aneurysm

Risk factors

Most are the usual heart-disease risk factors:

• High LDL cholesterol; low HDL
• High blood pressure
• Diabetes
• Smoking and tobacco
• Central (belly) obesity — particularly important in South Asians
• Physical inactivity
• Unhealthy diet — high in saturated/trans fats, refined carbs, salt
• Chronic inflammation (including from conditions like rheumatoid arthritis, severe infections)
• Family history of early heart disease
• Age, male sex
• Chronic kidney disease
• Stress, poor sleep
• Air pollution

Diagnosis

• Often diagnosed by the events it causes — heart attack, stroke, or claudication
• Screening lipid profile, blood pressure, blood sugar — identify risk factors before disease appears
• ECG, echocardiogram
• Coronary calcium score (CT) — detects plaque in coronary arteries
• Angiography — for specific evaluation
• Ankle-brachial index for leg arteries
• Carotid ultrasound for neck arteries

Treatment and prevention

• Stop smoking completely — including bidis and smokeless tobacco
• Control blood pressure — medicines plus lifestyle; regular checks
• Manage cholesterol — diet first, then statins and other medicines if needed
• Control diabetes
• Diet — more vegetables, fruits, whole grains, pulses, nuts; less salt, sugar, saturated fat, trans fats, refined flour
• Regular exercise — at least 150 minutes of moderate activity per week
• Maintain healthy weight, track waist size
• Manage stress, sleep well
• Antiplatelets — sometimes prescribed for people with established disease; balance of benefits and bleeding risk — don't self-start
• Angioplasty, bypass surgery — for severe symptomatic disease

Atherosclerosis is the most common cause of death globally — but it is also, to a very large extent, preventable. The risk factors can mostly be modified with consistent lifestyle and medical care over years.