When the air turns thick and hazy, most of us think about our lungs. We worry about coughs, wheezing and breathlessness, and we reach for masks and air purifiers. But the story does not stop at the chest. A growing body of research is now looking at what polluted air could be doing to other parts of the body, including the kidneys.
We spoke to a pulmonologist and a nephrologist about how fine particles travel beyond the lungs, who may be most at risk, and the simple steps that can help.
Pollution is not just a lung problem
Air pollution is often linked with coughing, wheezy breathing, and asthma, among other problems related to respiration; however, it also has implications for other organs of the body. “The particles we breathe in may cause an inflammatory reaction within the body,” says Dr. Vikas Mittal, Director - Pulmonologist, CK Birla Hospital, Delhi.
Air pollution is “increasingly being investigated not only for its harmful effects on the respiratory system but also for its impact on other organs, including kidneys,” says Dr. Anupam Roy, Additional Director - Nephrology and Kidney Transplant, Aakash Healthcare Multi-Speciality Hospital, Dwarka.
How tiny particles reach the kidneys
“Fine particulates, or PM2.5 in particular, have fine particles that can go deep into the lungs, as some of their components may enter the blood, leading to body inflammation and oxidative damage,” Dr. Mittal explains.
Explaining further, Dr. Roy says that fine particulate matter may enter the bloodstream, leading to processes like systemic inflammation and oxidative stress affecting kidney arteries and their ability to filter.
“These biological processes have been researched for their role in causing damage to the kidney,” Dr. Mittal says, adding that the lungs are the first organs in contact with polluted air, which can cause inflammation with the potential to affect the human body overall.
What the research says so far
According to Dr. Mittal, studies show that there is a relationship between long-term exposure to air pollution and the risk of chronic kidney issues. However, more research is still needed to understand how and how much the relationship is formed.
“In addition, pollution may harm the kidneys indirectly, for example, by worsening hypertension, affecting insulin resistance, and cardiovascular health,” he explains. “Nonetheless, the issue is complex, and the role of air pollution should be seen as a contributing factor and not the only cause of chronic kidney disease,” Dr. Roy adds.
Who may be at higher risk
“Patients with diabetes, hypertension, renal disease, and elderly individuals may be at maximum risk because they may already have compromised kidneys,” Dr. Roy says. “This is concerning since renal disease can develop without any symptoms in the initial stages,” he adds.
“It is important to regard polluted air as a multisystem issue rather than solely a respiratory one,” Dr. Mittal says. “People with pre-existing lung and heart diseases need to follow more careful protocols in times of pollution,” he adds.
Simple steps to reduce your exposure
“Some actions in this regard may include checking AQI levels locally, minimising exposure to polluted air conditions, staying away from smoking, and improving the quality of indoor air,” Dr. Mittal says.
“People should avoid engaging in vigorous outdoor activities on days of high pollution and refrain from smoking,” Dr. Roy advises. “In addition, people suffering from diabetes and hypertension should visit their doctor regularly to discuss kidney-monitoring options,” he adds.
The haze outside does not just stay outside. Fine particles that start their journey in the lungs can end up affecting the rest of the body, kidneys included. You cannot clear the air on your own, but you can check the AQI, cut back on outdoor exertion on bad days, stay away from smoke and keep up with regular check-ups, especially if you have diabetes or high blood pressure. Because your lungs are not the only ones breathing that air.