Invisible harms

By C.H. and R.J.

The toll of mental illness and substance abuse by age

THEY account for a relatively small share of the world’s premature deaths—but they are the biggest drivers of disability. Mental disorders and drug and alcohol abuse account for 7.4% of disability-adjusted life years (DALYs), a metric that combines years of life lost to ill-health and early death. Together they result in more DALYs than diabetes, HIV or tuberculosis, and about as many as cancer. Depression and anxiety peak for young adults, causing around 11m lost years of healthy life in the 20- to 24-year-old age group globally. Little wonder many turn to drugs, which peaks at about those ages too. The prevalence of disorders varies by sex. Drug and alcohol problems are more common among men. Mental ailments take a greater toll on women, except for in early childhood, when boys suffer more. The data come from a new tally by Harvey Whiteford of the University of Queensland and his colleagues, published in the Lancet. Regional differences were also examined. Eastern Europe seems to drown its sorrows in drink: it has the world's highest burden of both depressive and alcohol disorders.