Why Polluted Air May Be a Threat to Your Kidneys

Jessie Fidler wrote . . . . . . . . .

There is good evidence that polluted air increases the risk of respiratory problems such as asthma — as well as organ inflammation, worsening of diabetes and other life-threatening conditions.

But new research suggests air pollution can also fuel something else: chronic kidney disease, or CKD, which occurs when a person’s kidneys become damaged or cannot filter blood properly.

Recently published in PLOS One, a University of Michigan study highlights the lesser-known connection.

“Similar to smoking, air pollution contains harmful toxins that can directly affect the kidneys,” says Jennifer Bragg-Gresham, M.S., Ph.D., a Michigan Medicine epidemiologist and the study’s lead author.

“Kidneys have a large volume of blood flowing through them, and if anything harms the circulatory system, the kidneys will be the first to sense those effects.”

People with diabetes, obesity, high blood pressure or heart disease are at increased risk of developing CKD. Which is why high-risk patients who live in heavily populated or polluted areas should recognize the danger and take precautions, Bragg-Gresham says.

Why air pollution is dangerous

Air pollution contains fine particulate matter, or PM2.5, which is a cocktail of microscopic particles.

Because these particles are virtually weightless, they can stay in the air longer, causing humans to unavoidably inhale them on a regular basis without knowing it. PM2.5 can lead to serious health effects when inhaled often.

By reviewing Medicare claims data and air-quality data from the Centers for Disease Control and Prevention, the study’s authors found a positive association between CKD rates and PM2.5 concentration.

Says study co-author Rajiv Saran, M.D., a Michigan Medicine nephrologist and director of the United States Renal Data System Coordinating Center at U-M: “If you look at areas that are heavily polluted versus areas that are less polluted, you will find more chronic kidney disease.”

According to figures cited in the new research, chronic kidney disease afflicts more than 27 million Americans. People with CKD have an eightfold increased risk of cardiovascular mortality.

Unfortunately, PM2.5 is almost impossible to avoid.

We encounter air pollution from many simple everyday activities, such as cooking and driving. Other contributors are smoking, burning wood, packaged spray products, household appliances and, perhaps the most obvious, industry and vehicle emissions.

Air pollution also contains heavy metals such as lead, mercury and cadmium — all of which are known to negatively affect the kidneys.

Problems and preventive measures

The U-M research examined several prior studies on the issue, including an effort conducted in select coal-mining areas of Appalachia that found a 19 percent higher risk of CKD among men and a 13 percent higher risk in women compared with those who lived in counties with no mining.

The good news: PM2.5 levels are much lower in the U.S. than in other industrialized countries such as China and India.

“What this means for the countries with higher PM2.5 is significantly higher odds of CKD,” says Bragg-Gresham, also an assistant research scientist at U-M. “Our research was only able to examine a small range of PM2.5 values present in America but was able to find a significant association.”

However, it’s still important to take precautions when exposed to air pollution, especially for people who have existing health conditions or who live in densely populated or polluted cities.

“In heavily polluted areas, consider wearing masks that cover your nose and mouth, limit hours outside and limit long hours commuting to work in high traffic as well,” Saran says, adding that the risk should be taken seriously.

“Many people don’t see the seriousness of air pollution because it isn’t something visible, but that doesn’t mean it’s any less important for your health.”

Source: University of Michigan


Today’s Comic

Advertisements

Poor Air Quality Does Not Offset Exercise’s Heart Benefits

Even in areas with moderate-to-high levels of traffic pollution, regular physical activity reduced the risk of first and recurrent heart attack, according to new research in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.

“While exercise is known to reduce cardiovascular disease risk; pollution can increase the risk of cardiovascular disease, including heart attacks, asthma and chronic obstructive lung disease,” said Nadine Kubesch, Ph.D., lead author and researcher at the University of Copenhagen in Denmark. “Currently there is little data on whether poor air quality cancels out the protective benefits of physical activity in preventing heart attacks.”

Researchers in Denmark, Germany and Spain evaluated outdoor physical activity levels (sports, cycling, walking and gardening) and nitrogen dioxide (NO2 pollutant generated by traffic) exposure in 51,868 adults, age 50-65, comparing self-reported activities and lifestyle factors against heart attack. Over a 17.7-year period, there were 2,936 first heart attacks and 324 recurrent heart attacks.

To estimate average NO2 exposure, researchers used national traffic pollution monitoring data for each participants’ address and found:

  • Higher levels of were associated with more heart attacks, however, the risk was lower among those who were physically active.
  • Moderate cycling for four or more hours per week cut risk for recurrent heart attack by 31 percent; and there was a 58 percent reduction when all four types of physical activity (together totalling four hours per week or more) were combined, regardless of air quality.
  • Those who participated in sports had a 15 percent lower rate of initial heart attacks and there was a 9 percent risk reduction associated with cycling, regardless of air quality
  • Compared to participants with low residential NO2 exposure, those in higher risk areas had a 17 percent increase risk in first heart attack and 39 percent for recurrent heart attack.

In particiants who developed a heart attack (first or recurrent), the average NO2 exposure level was 18.9 microgramm per cubic meter air (μg/m3) with an overall average of 18.7 μg/m3, which is below the current NO2 European Union exposure guideline (50 μg/m3 over 24 hours).

“Our study shows that physical activity even during exposure to air pollution, in cities with levels similar to those in Copenhagen, can reduce the risk of heart attack,” Kubesch said. “Our research supports existing evidence that even moderate levels of regular physical activity, such as active commuting, are suffienciently intense to get these health benefits.

Source: American Heart Association


Today’s Comic

Air Pollution May Account for 1 in 7 New Diabetes Cases Worldwide

Anne Harding wrote . . . . . . .

Air pollution could be responsible for 3.2 million new cases of type 2 diabetes every year globally, suggests a new analysis.

“We estimate that about 14 percent of diabetes in the world occurs because of higher levels of air pollution, that’s one in seven cases,” said senior study author Dr. Ziyad Al-Aly of Washington University and the VA Saint Louis Health Care System in Missouri.

“Risks exist at levels that are below what’s now currently considered safe by the Environmental Protection Agency (EPA) in the United States and also by the World Health Organization,” he told Reuters Health in a phone interview.

The tiniest form of particulate matter pollution, known as PM 2.5, is already associated with increased risk of heart disease, lung disease, kidney disease, and other noncommunicable diseases “and contributed to about 4.2 million premature deaths in 2015,” the study team writes in The Lancet Planetary Health.

PM 2.5 is the mix of solid fragments and liquid droplets suspended in air that’s sometimes visible to human eyes as haze.

“There is emerging evidence over the past several years that particulates, when they are small enough, they make their way through the lungs to the blood vessels,” Al-Aly said. “They go to the liver, they go to the pancreas, they go to the kidneys. These particles are noxious. They irritate tissue and they damage tissue, they create oxidative stress, they create inflammation.”

Type 2 diabetes is associated with obesity and aging and occurs when the pancreas can’t make or process enough of the hormone insulin.

To look for a link between air pollution and type 2 diabetes, researchers analyzed data on 1.7 million U.S. veterans without diabetes, comparing PM 2.5 levels where they lived to their risk of being newly diagnosed with the disease during the next eight and a half years, on average. The researchers separated out the independent effect of air pollution by taking other diabetes risk factors, like obesity, into account.

Veterans’ annual average daily PM 2.5 exposure ranged from 5 to 22.1 micrograms per cubic meter (mcg/m3) of air. A 10-point increase in PM 2.5 concentration was associated with a 15 percent higher risk of developing diabetes, and an 8 percent higher risk of death. Risk of diabetes started to rise when pollution levels exceeded 2.4 mcg/m3, well below the EPA’s current standard of 12 mcg/m3 and the World Health Organization guideline of 10 mcg/m3.

Al-Aly and his colleagues then looked at worldwide PM 2.5 levels to estimate the total burden of diabetes due to air pollution. About 3.2 million new cases of diabetes, 8.2 million years of life lost to disability and more than 200,000 deaths annually were attributable to breathing dirty air, the authors calculated. Low-income and low-to-middle income countries bore the largest burden of air pollution-related diabetes.

While air in the U.S. is relatively clean compared to smog-choked parts of China, India and elsewhere, Al-Aly said, “we need to do better.”

He called for moving to “energy sources that contribute much less to pollution, more electric cars, more hybrid cars, more solar power and wind sources of energy rather than coal. It’s already happening, but probably not fast enough.”

In an editorial, Dr. Gary O’Donovan of the Universidad de los Andes in Bogota, Colombia, and Dr. Carlos Cadena-Gaitan of the Universidad EAFIT in Medellin, call the findings “another call for action.” They note that the current study did not adjust for physical activity, and that it’s possible to cut air pollution while promoting exercise with programs like Bogota’s Cyclovia, in which city roads are closed to motor vehicles on Sundays and holidays to make room for walkers and cyclists.

“More research is required to determine the independent associations of physical activity and air pollution with diabetes and other non-communicable diseases; nonetheless, there is more than enough evidence to justify the implementation of policies and interventions that might actually increase physical activity and decrease air pollution, such as Cyclovias, free sport and exercise facilities, bicycle sharing schemes, electric vehicles, low sulfur fuels, exhaust filters, and driving prohibition schemes,” they write.

Source: Reuters


Today’s Comic

Even at ‘Safe’ Levels, Air Pollution May Boost Diabetes Risk

Add another health harm to air pollution: New research suggests it might increase the risk of diabetes, even at levels considered safe.

Cutting air pollution could reduce diabetes rates in countries with both higher and lower levels of air pollution, the researchers said.

“Our research shows a significant link between air pollution and diabetes globally,” said study senior author Dr. Ziyad Al-Aly. He’s an assistant professor of medicine at Washington University in St. Louis.

“We found an increased risk, even at low levels of air pollution currently considered safe by the U.S. Environmental Protection Agency and the World Health Organization,” Al Aly said in a university news release.

“This is important because many industry lobbying groups argue that current levels are too stringent and should be relaxed. Evidence shows that current levels are still not sufficiently safe and need to be tightened,” he added.

But the findings did not prove that air pollution causes diabetes.

In the study, the researchers estimated that air pollution contributed to 3.2 million new diabetes cases worldwide in 2016, or about 14 percent of all new cases that year. They also estimated that 8.2 million years of healthy life were lost worldwide in 2016 due to pollution-linked diabetes.

In the United States, air pollution is linked with 150,000 new cases of diabetes a year and 350,000 years of healthy life lost each year, according to the report.

Diabetes affects more than 420 million people worldwide and 30 million Americans. The main causes of type 2 diabetes include an unhealthy diet, inactivity and obesity, but this study highlights the significance of outdoor air pollution.

It’s believed that air pollution reduces insulin production and triggers inflammation, preventing the body from converting blood sugar into energy that the body needs to maintain health, the study authors explained.

The study was published in The Lancet Planetary Health.

Previous research has linked air pollution with heart disease, stroke, cancer and kidney disease.

Source: HealthDay

Even at ‘Safe’ Levels, Air Pollution Puts Seniors at Risk

For older people, breathing in dirty air puts them at risk of being hospitalized with a dangerous respiratory disease, a new study suggests.

Among U.S. seniors, hospital admissions for acute respiratory distress syndrome (ARDS) rose as levels of both ozone and fine particulate matter increased — even when the pollutants were within levels now considered safe, the researchers said in a news release from the American Thoracic Society.

“While there is growing evidence of the impact on lung health of numerous air pollutants, there have been few studies that have looked at acute respiratory diseases and air pollution across large populations,” said lead author Jongeun Rhee. She is an epidemiologist at Harvard’s T.H. Chan School of Public Health in Boston.

Rhee and her colleagues analyzed data from nearly 30 million Medicare beneficiaries who were discharged from U.S. hospitals from 2000 through 2012. Using ZIP codes, the investigators were able to calculate seniors’ annual exposure to fine particulate matter, or PM2.5, in the air as well as to ozone from April through September.

The researchers also developed models that allowed them to link pollution levels with hospitalizations due to ARDS. They found a significant link between changes in levels of fine particulate matter and ARDS admission rates among older people.

While the study found a connection between pollution and hospitalization for ARDS, it didn’t prove a link.

ARDS is a progressive, often fatal, disease that causes fluid to leak into the lungs, making breathing difficult or impossible, the study authors explained. Older people and those with serious health issues — such as sepsis, pneumonia or traumatic injury — are at greater risk.

“We highlighted the importance of air pollution as an environmental risk factor for ARDS, which has not been studied widely but contributed to a previous finding that was limited to ozone,” Rhee said in the news release.

The study also found that ARDS admissions increased even when older people were exposed to pollution levels that were within National Ambient Air Quality Standards.

The study’s senior author, Dr. David Christiani, is a professor of environmental genetics at T.H. Chan School of Public Health.

He said the “findings are unique in showing that the adverse health effects of air pollution on our senior citizens now include acute respiratory failure, and that an increase in hospitalization for ARDS in seniors occurs at the current U.S. air pollution standards.”

He went on to say that “these results add to the growing body of literature on various adverse health effects at current standards that demonstrate a need to lower our exposure limits.”

The study was scheduled for presentation Wednesday at the annual meeting of the American Thoracic Society, in San Diego. Research presented at meetings should be viewed as preliminary until published in a peer-reviewed journal.

Source: HealthDay


Today’s Comic