World Diabetes Day: Study from Delhi and Chennai Finds Alarming Link Between Type-2 Diabetes and Air Pollution

We have always known that there are marked urban-rural differences in the prevalence of diabetes with urban areas having much higher prevalence rates.

Till now, it was believed that the higher prevalence in urban areas was due to greater affluence which led to unhealthier diets higher in calories, decreased physical activity and probably the stress associated with urban living.

However, the recent CARRS study done at Chennai and Delhi funded by the NIH, has found a new link to Type-2 diabetes through air pollution.

It was seen that even after correcting for all the known confounders like family history of diabetes, obesity, diet and physical activity, air pollution was associated with new-onset type 2 diabetes both in Delhi and Chennai.

How does air pollution contribute to diabetes?

It is now known that air pollution can act as an endocrine disruptor. Thus, it can interfere with both insulin secretion from the pancreas as well as its action in the liver and muscle, the very defects which lead to diabetes, in the first place.

It is now known that a fifth of the burden of Type-2 diabetes (T2D) worldwide may be attributable to air pollution, with a larger share coming from ambient PM 2.5 and the rest from household air pollution.

With the growing socio-economic development worldwide, the detrimental health effects of air pollutants are receiving increased attention.

Air pollutants are broadly classified into gaseous pollutants and atmospheric particulates.

Gaseous pollutants include sulphur compounds, nitrogen compounds, carbon oxides, hydrocarbons, and halogen compounds and atmospheric particulates include total suspended particulates, inhalable particles (PM10), fine particulate matter (PM2.5), and ultrafine particulate matter.

Type 2 diabetes mellitus and air pollution are critical public health concerns worldwide.

The biological mechanisms underlying this association include immune activation, endoplasmic reticulum stress, central nervous system inflammation, and oxidative stress.

A recent study in India assessed the association of PM2.5 exposure, glycemic markers and incidence of Type 2 diabetes in two urban cities, viz., Delhi and Chennai and provides evidence linking short-term, medium-term and long-term exposure to PM2.5 and incident T2D.

The study assessed PM2.5 from locally developed high-resolution spatiotemporal models and showed a clear association between PM2.5 and incident diabetes.

The evidence offers guidance for developing and implementing population and region-specific policies aimed at lowering ambient air pollution in order to combat the high prevalence of diabetes.

What can we do to prevent diabetes knowing the link between air pollution and diabetes?

Firstly, we should try to reduce pollution. We know the major sources of air pollution are either the burning of stubble by farmers, smoke from vehicles, industrial pollution, use of firewood or charcoal in ill-ventilated kitchens or indiscriminate pollution during festivals like Diwali due to fireworks, etc.

All these are potentially preventable by legislation, education and governmental and non-governmental agencies. Wearing a mask as we did when we had COVID-19 is a very good way to prevent particulate matter from entering our bodies through the nose or mouth.

This is, in fact, a golden opportunity to prevent not only respiratory diseases but also metabolic diseases like diabetes by reducing pollution. THE TIME FOR ACTION IS NOW!

(Dr. Mohan is Chairman & Chief of Diabetology, Dr. Mohan’s Diabetes Specialities Centre & President, Madras Diabetes Research Foundation, Chennai, India. He is also Head of MDRF-Hinduja Foundation T1D program).

**

The above article has been published from a wire agency with minimal modifications to the headline and text.