Eric Thayer / Reuters For the last several months, social scientists have been debating the striking findings of a study by the economists Susan Case and Angus Deaton. Between 1998 and 2013, Case and Deaton argue, white Americans across multiple age groups experienced large spikes in suicide and fatalities related to alcohol and drug abuse—spikes that were so large that, for whites aged 45 to 54, they overwhelmed the dependable modern trend of steadily improving life expectancy.