A new study by researchers at the University of Colorado provides compelling evidence that the condition of older people and women with atrial fibrillation who live near oil and natural gas wells may worsen during development of these sites.
The phase when a well is being developed is when the most activity occurs on the drilling platform, Lisa McKenzie, a researcher at the Colorado School of Public Health and lead author of the study, said in an interview. “It really seems to be focused on that development phase of the well,” she said.
“They’re drilling, they’re fracking, there’s a much higher potential for noise and air pollutant emissions at the drilling site,” said McKenzie, an associate professor in CU Anschutz’s Department of Environmental and Occupational Health. “The closer you got to the drilling site, the higher the risk was.”
Atrial fibrillation is an irregular and often rapid heart rhythm, also called an arrhythmia. According to the Mayo Clinic, it can lead to blood clots in the heart and increase the risk of stroke, heart failure, and other heart complications.
Atrial fibrillation is the most common form of abnormal heart rhythm. According to Yale Medicine, it affects up to 6.1 million people in the United States at any given time and approximately 450,000 people are hospitalized each year.
The study found that patients with atrial fibrillation who were older than 80 years and lived near oil and natural gas wells (defined as 0.63 kilometers (2059 feet)) had an 83 percent increased risk of worsening symptoms associated with atrial fibrillation, including heart palpitations, chest pain and dizziness. This group of patients also doubled their risk of visiting the emergency room for symptoms associated with the condition.
In patients with atrial fibrillation who lived near oil and gas wells, the risk of the disease worsening was increased by 56 percent.
The researchers found that the increased risk extended to within nearly a mile (1.3 km or 1,200 m) of the drilling sites, but did not persist after the wells were developed.
The study found no comparable increases among younger people and men.
“I think this issue really deserves more attention and more thorough investigation,” McKenzie said, noting that the information could be useful to regulators in making decisions about building wells and to health care providers in counseling patients who may live near wells.
At least 6 percent of Colorado’s population lives within a mile of an active oil and natural gas production site, and wells are not allowed to come closer than 2,000 feet to homes, McKenzie said.
Previous studies have linked atrial fibrillation to exposure to air pollution and noise, but McKenzie said this study did not directly measure noise and air pollution levels, so researchers could not determine specific associations.
The research team followed 1,197 patients with atrial fibrillation who lived within one mile of an oil or natural gas well and 9,764 patients with atrial fibrillation who lived more than two miles away after the wells were drilled.
They used data from Colorado’s All Payer Claims Database, a database that provides anonymized data on the health status of most people with health insurance in the state, including Medicaid and Medicare. The study also considered other key factors such as chronic conditions, personal behavior and regional environmental trends.
The research was published in the peer-reviewed journal Frontiers in Epidemiology. It was conducted at the Colorado School of Public Health on the CU Anschutz Medical Campus. Study co-authors include William Allshouse and Dr. Barbara Abrahams, both of CU Anschutz, and Dr. Christine Tompkins of Emory University.
A spokesman for the Colorado Oil and Gas Association said they had not yet had a chance to review the results and declined to comment.
The research was funded by the National Institutes of Health and the Center for Improving Value in Health Care.
“Studies like this provide Colorado School of Public Health faculty and researchers with an opportunity to inform policymakers and guide regulators in developing mitigation strategies that ultimately protect the health and well-being of Coloradans,” said Travis Leiker, CU Anschutz’s associate dean for external relations, in a press release.
A 2019 Anschutz study from the University of Colorado, in which McKenzie was the lead author, found that mothers who lived near more intense oil and gas production had a 40 to 70 percent higher risk of having children with congenital heart defects.
The researchers studied more than 3,000 babies born in Colorado between 2005 and 2011. McKenzie said the research found that more children were born with congenital heart defects in places with the highest oil and gas activity than in areas with less or no oil and gas activity.
The Colorado Oil and Gas Association said the data McKenzie used in his study was outdated. They said the researchers “used data that is not relevant to current regulations or the common practices of today’s operators.”
McKenzie said more studies are needed, and pointed to some limitations of the AFib study. One is that the claims database does not include the state’s uninsured population, which makes up about five percent of Colorado residents. “The risk might be a little higher if we only had AFib patients,” McKenzie said.
The researchers also said they assumed that a patient’s address in the database of all payers was also the address of their actual place of residence. This is probably the case for most people, but there may be a few people who have an address where they do not actually live.
