The study was on those over 65, so in terms of London smog and India; life expectancies lower so maybe if data available similar signals might be very difficult/impossible to detect.
> Or into the future with high EV cities and a drop in PM2.5?
We can hope but - tire wear produces similar sized micro plastic pollution [0] and electric cars are heavier and are likely to produce more of them [1]. Add into mix that chemically different make up and who knows [2]