World Stroke Day 2025: Top 6 Risk Factors That Increase Stroke Chances

A stroke can strike suddenly, but it's rarely without warning. As India observes World Stroke Day 2025 (October 29), doctors are urging people to recognise and manage modifiable risk factors that account for nearly 90% of stroke cases globally. According to the World Health Organization (WHO), stroke is the second leading cause of death and disability worldwide, and India has seen a steep rise in incidence, especially among younger adults. Lifestyle-related factors such as hypertension, smoking, diabetes, and physical inactivity have become key contributors to this growing crisis.

"Stroke is a medical emergency that requires immediate attention, but prevention begins much earlier," says Dr Rajnish Kumar, Principal Director & Unit Head, Neurology, Max Super Speciality Hospital, Dwarka. "Most of the major risk factors for stroke are modifiable, meaning they can be managed or controlled through timely lifestyle and medical interventions."

Here are the six top risk factors that significantly increase your chances of having a stroke, and what science says about reducing your risk.

1. High Blood Pressure (Hypertension)

"High blood pressure is the most important risk factor for stroke," says Dr Rajnish Kumar. "Uncontrolled hypertension can increase your risk of stroke by up to four times." Over time, high pressure damages and weakens artery walls, making them prone to rupture (causing hemorrhagic stroke) or blockage by plaque (causing ischemic stroke). A study published in The Lancet Global Health (2022) found that nearly one in three Indian adults has hypertension, yet less than 25% have it under control.

2. Smoking (Tobacco Use)

"Nicotine raises blood pressure, while carbon monoxide reduces the oxygen-carrying capacity of blood," explains Dr Kumar. "Both smoking and exposure to second-hand smoke nearly double the risk of an ischemic stroke and increase the risk of haemorrhagic stroke." According to the Centers for Disease Control and Prevention (CDC), smokers have a two- to fourfold higher stroke risk compared to non-smokers. Even passive exposure to tobacco smoke increases the likelihood of clot formation.

3. Heart Disease

Various cardiac conditions, particularly atrial fibrillation (AFib), can create blood clots that travel to the brain. "Atrial fibrillation causes blood to pool in the heart's upper chambers, forming clots that may later travel to the brain," Dr Kumar explains. "Heart failure and valve diseases also significantly increase stroke risk." Research from the American Heart Association (AHA) shows that people with AFib are five times more likely to suffer a stroke.

4. Diabetes

"Diabetes damages blood vessels throughout the body, including those in the brain," says Dr Kumar. "High blood sugar leads to the buildup of fatty deposits and blood clots inside arteries." Many people with diabetes also have other risk factors, hypertension, obesity, and high cholesterol, compounding their stroke risk. A 2023 study in the Journal of Stroke found that diabetic patients have a 1.8 times higher risk of ischemic stroke than non-diabetics.

5. High Cholesterol

High levels of LDL or "bad" cholesterol contribute to atherosclerosis, a condition where plaque builds up inside arteries. If these plaques rupture, they can block blood flow to the brain. "Managing cholesterol through diet, medication, and regular monitoring is essential," advises Dr Kumar. "It helps prevent fatty buildup that can cause a stroke." The National Institutes of Health (NIH) reports that lowering LDL cholesterol by 1 mmol/L can reduce ischemic stroke risk by over 20%.

6. Obesity and Physical Inactivity

"Being overweight increases your chances of developing high blood pressure, heart disease, and diabetes - all major stroke risks," Dr. Kumar notes. Even independent of body weight, a sedentary lifestyle is linked to higher stroke risk. Regular exercise, like brisk walking for 30 minutes most days, can reduce stroke incidence by up to 25%, according to the Harvard T.H. Chan School of Public Health.

Stroke prevention begins with awareness, and action. "Know your numbers," Dr Kumar urges. "Keep your blood pressure, sugar, and cholesterol under control. Quit smoking, stay active, and maintain a healthy weight. These are the simplest yet most powerful ways to reduce your stroke risk."

On World Stroke Day 2025, remember the campaign's global message: 'Together We Can Outpace Stroke.' Regular health checks, timely medical advice, and small daily lifestyle changes can make a life-saving difference.

Disclaimer: This content, including advice, provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.