Affluence, age, and motor neuron disease.

by over fivefold (figure), and the rises were larger in middle and older age than in children and young adults.3 This discrepancy therefore indicates that the rises in asthma mortality cannot simply be related to increased incidence or prevalence of severe asthma requiring hospital admission. Assuming that data on asthma mortality are satisfactorily reliable, and that the determinants of hospital admission have not dramatically changed, this would suggest that