In a first-of-its-kind study, researchers have found that air pollution can play a role in the development of cardiometabolic diseases such as diabetes. Moreover, the study also shows that living in a polluted region was comparable to eating a high-fat diet.
A team of researchers from the Case Western Reserve University and John Hopkins Bloomberg School of Public Health in the US, led by Indian-origin scientist Dr Sanjay Rajagopalan, made the discovery. The study shows that air pollution was a ‘risk factor for a risk factor’ that formed the underlying cause of fatal problems like heart attack and stroke.
“In this study, we created an environment that mimicked a polluted day in New Delhi or Beijing,” Dr Rajagopalan said. “We concentrated fine particles of air pollution called PM2.5. Concentrated particles like this develop from human impact on the environment, such as automobile exhaust, power generation and other fossil fuels.”
The fine pollution particles have been strongly linked to risk factors for several diseases like lung cancer, heart failure, Alzheimer’s and other chronic diseases. Air pollution is the deadliest environmental hazard in the current times, with an estimated death toll of more than 90 lakh per year. The evidence for the cardiovascular effects of air pollution can lead to heart attack and stroke and cardiometabolic diseases like diabetes is also growing.
In the present research, the results show that air pollution can be added as a risk factor for the development of such cardiometabolic diseases similar to an unhealthy diet and lack of exercise. The research team has shown exposure to air pollution can increase the likelihood of the same risk factors that lead to heart diseases, such as insulin resistance and type 2 diabetes.
In its statement, the University Hospitals Cleveland Medical Center explains that the mouse model study involved three groups: a control group receiving clean filtered air, a group exposed to polluted air for 24 weeks, and a group fed a high-fat diet. Both the pollution-exposed group and the high-fat diet group showed insulin resistance and abnormal metabolism—similar to a pre-diabetic state.
“The good news is that these effects were reversible, at least in our experiments. Once the air pollution was removed from the environment, the mice appeared healthier, and the pre-diabetic state seemed to reverse,” said Dr Rajagopalan.
The results could have a significant contribution in responding to severe heart attack and other such cardio-related risks. As a next step, the researchers are planning to involve more experts and the National Institute of Health, to explore the possibility of clinical trials to compare heart health and the level of air pollution.
The researchers are hopeful that the study will encourage policymakers to act on the reduction of air pollution in highly polluted regions like India and China.
The study was published in the Journal of Clinical Investigation last week.