Offsetting Behavior, Medical Breakthroughs, and Breakdowns

Progress against mortality risk has contributed importantly to growth in the stock of human capital. This progress is occasionally accelerated by unexpected medical breakthroughs. However, sudden gains against one risk can induce offsetting increases in other risks. I examine this possibility empirically with data from three unexpected changes in mortality risk: the introduction of antibiotics, discovery of new treatments for heart disease, and the AIDS epidemic (an unexpected breakdown of progress). I find that offsetting responses can provide a unifying explanation for important features of data from these three different episodes. These features include increased noninfectious disease mortality in groups most benefited by antibiotics, a connection between heart disease gains and increased obesity, and declining external cause mortality risks in vulnerable groups in places with high AIDS incidence.