Growing Stroke Deaths Linked to Climate Change

Extreme temperatures caused by climate change may be linked to increasing death and disability from stroke, a new study suggests.

Climate change has been associated with a vast variety of health risks, including prolonged pollen allergy season, more widespread insect-borne diseases, and premature deaths.

Some scientists call rising temperatures due to climate change the greatest threat to global public health.

A new study that was published in the journal Neurology suggests that about half a million stroke deaths globally may be associated with extreme temperatures, extending the list of health risks posed by climate change.

The researchers looked at 30 years of health records for more than 200 countries and territories.

They examined the number of stroke deaths and the burden of stroke-related disability due to non-optimal temperatures — those above or below temperatures associated with the lowest death rates.

In 2019, there were 521,031 stroke deaths and 9.4 million disability-adjusted life years due to stroke linked to non-optimal temperatures. Disability-adjusted life years are the number of years lost due to premature death or years lived with illness.

Low temperatures were linked to 474,002 of the total deaths. When the temperature drops, a person’s blood vessels can constrict, increasing blood pressure, which is a risk factor for stroke.

Higher-than-optimal temperatures can also raise the risk, as they can cause dehydration, affect cholesterol levels, and result in slower blood flow.

The rate of death from stroke from temperature changes for male participants was 7.7 per 100,000 compared to 5.9 per 100,000 for female participants.

“More research is needed to determine the impact of temperature change on stroke and to target solutions to address health inequalities,” said study author Quan Cheng, Ph.D., of Xiangya Hospital Central South University in Changsha, China.

Healthy living for stroke prevention

Changing temperatures is far from being the only risk factor for stroke. The Centers for Disease Control and Prevention recommends preventing stroke by making healthy lifestyle choices:

• Follow a healthy diet low in saturated fats and trans fats. A diet high in fiber — found in fruits, vegetables, and whole grains — can help prevent high cholesterol. Limit your intake of salt (sodium) to lower your blood pressure.
• Keep a healthy weight — being overweight or having obesity increases the risk of stroke.
• Exercise regularly to maintain a healthy weight and lower cholesterol levels and blood pressure. Adults need at least 2 hours and 30 minutes of moderate-intensity aerobic physical activity a week.
• Don’t smoke and limit alcohol consumption — there is no safe amount of alcohol.
• Check cholesterol at least once every five years and measure your blood pressure levels.
• Control diabetes and heart disease, such as coronary artery disease or irregular heartbeat.

The study does not prove that climate change causes stroke; it only shows an association. While individuals have little control over changing temperatures, they can adopt healthy habits to reduce the risk of stroke and many other chronic conditions.