Apart from smartphones, London’s teenagers now have another nemesis that can abnormally increase their blood pressure. King’s College London recently conducted a new study published in PLOS One journal, which observes that air pollution in London can cause an increase in the systolic blood pressure of adolescents. The study suggests that a nominal increase of 1 μg/m3 (microgram per cubic metre) in PM2.5 levels in the atmosphere can spike the systolic blood pressure of girls by 1.34 mmHg (millimetres of mercury) and by 0.57 mmHg in boys.
Similarly, when we talk of nitrogen dioxide levels in air, an increase of 1 μg/m3 reduces the systolic blood pressure by 0.30 mmHg in girls and by 0.19 mmHg in boys. As seen from these findings, girls have been affected more by these pollutants in comparison with boys. A similar study was conducted by the University of Michigan where air pollution was found to be directly linked to obesity in women in America.
Systolic blood pressure is the bigger number on a sphygmomanometer, which tells the force exerted by the heart on the walls of arteries with every beat. Whereas diastolic blood pressure is the smaller number, which tells the pressure exerted by the heart on the walls of the arteries in between two consequent beats. The pollutants only impacted the systolic blood pressure of the subjects, whereas no impact was seen over their diastolic blood pressures.
Since adolescents grow at a faster pace than adults, they could have been more prone to the negative impacts of these pollutants. As previous studies mostly revolved around the impacts of air pollution on adults, this research brings fresh insights into the issue. In contrast to their white classmates, kids hailing from ethnic minorities were more susceptible to this damage as they were exposed to higher levels of PM2.5 and NO2.
The findings of this study are astounding and statistically significant as it involved school kids from various backgrounds. About 80 percent of the 3,284 subjects came from ethnic minorities of the city. This research was conducted as part of the Determinants of Adolescent Social Well-Being and Health (Dash) study which monitors the health of thousands of ethnically diverse London school children over time. These students were enrolled during the time period of 2003-04 and were called for follow up in 2005-06. This study took into account their height, weight, blood pressure, socio-economic status, ethnicity, and area of residence.
The researchers agreed that effective measures need to be in place to reduce the level of PM2.5 and NO2 in London’s air since they are beyond the standard prescribed by WHO Guidelines.