Passive smoke and crossing a street

[Biochemist]

...If asthma is on the rise then how is respiratory disease on the decline if asthma is indeed a respiratory disease? Or or you stating only that respiratory disease attributed explicitly to air pollution is on the decline?...

Yes to the latter. The topic initially was whether air pollution is driving an increase in respiratory disease. The answer appears to be no, but there is a real increase in asthma unrelated (apparently) to air pollution.