Cardiovascular Death Due to Environmental Toxins Shows Decrease in Trends

Anoop Titus, MD

A 30-year comparison of cardiovascular disease (CVD) deaths associated with environmental toxins indicated lead exposure has contributed more to CVD death risks in the United States compared with the United Kingdom.

However, the data suggest the United States fared better when comparing CVD death risks linked to particulate matter to the United Kingdom.

“The good news is that the U.S. and the United Kingdom have been doing remarkably well at reducing certain environmental factors that may contribute to cardiovascular death,” said lead study author Anoop Titus, MD, Third-Year Internal Medicine Resident, St. Vincent Hospital in a press release. “However, despite reductions made, our study suggests that there is still a significant difference between the U.S. and the United Kingdom when comparing cardiovascular death risk factors such as lead and particulate matter.”

The findings were presented at the American Heart Association Scientific Sessions 2022 in Chicago.

Environmental exposure to toxins has been linked to the development and progression of CVD and in CVD-related deaths. Recurrent exposure has been associated with heart disease, high blood pressure, and hardening of arteries.

Titus and colleagues investigated the 30-year CVD in populations with environmental risk factors who died between 1990 and 2019 in Great Britain and the United States, selected from the 2019 Global Burden of Disease Study. It totaled 33 million deaths.

The team then calculated the proportion of CVD deaths associated with exposure to risk factors, including lead, particulate matter, secondhand smoke, and smoking. The analysis aimed to uncover the differences between the US and the United Kingdom due to each being high-income countries with similar risk factors and Western lifestyle.

In the analysis, the 30-year mean CVD death was compared using Welch’s t-test and the investigators estimated the trends of CVD deaths with risk factors over the total CVD rate.

The findings suggest the United States had a higher risk-attributable cardiovascular death rate associated with lead exposure, at 2.4% over the 30 years, compared with the United Kingdom.

By contrast, the United Kingdom had a more significant proportion of cardiovascular deaths associated with exposure to particulate matter at 6.5%, while the United States had 5.0% during the same period.

The data show no significant differences in cardiovascular deaths between the countries for smoking and exposure to secondhand smoke over the 30 years. Investigators noted the rate of risk attributed to cardiovascular death is the same as in 1990 and smoking remains the highest risk factor in both countries followed by particulate matter.

Investigators expected no differences between the US and the UK, due to similar public health policies to increase preventive care and environmental regulations to reduce exposure to toxins. Lead exposure was reported to be high in the US, but exposure to particulate matter has significantly reduced in the past 30 years.

In the analysis of trends for the four environmental factors, a steady decline in cardiovascular deaths associated with all factors in both countries was observed over the 30 years. The study did not report a direct cause between environmental toxins and the risk of cardiovascular death, but suggested a difference in cardiovascular mortality in demographically similar countries.

“Our study revealed that we are still tackling the beast,” Titus said. “Patient counseling by physicians and cardiologists is required to educate patients regarding these four environmental factors linked to cardiovascular disease.”

"More research on how environmental risk factors impact our daily lives is needed to help policymakers, public health experts, and communities see the big picture,” he added. “Better anti-smoking campaigns need to be developed as well as changes that move us away from fossil fuels.”

The oral abstract, “30 years of data: Lead and other environmental toxins linked to CVD deaths in U.S., United Kingdom,” was presented at AHA 2022.