Mental illnesses account for more suffering and premature death in rich countries than heart disease and strokes, or than cancer. One study estimates that depression is 50% more disabling than angina, asthma or arthritis. Men with mental-health problems die 20 years earlier than those without, according to the British Medical Association, mostly from causes other than suicide. That is partly because mental illnesses make physical ones tougher to treat, and because sufferers often live less healthily. Research has linked even moderate levels of stress to lower life-expectancy.
Half of adults with long-term mental conditions suffered their first symptoms before turning 14. Left untreated, even moderate conditions such as anxiety hurt school results and the prospects for employment. For serious conditions such as psychosis, prompt treatment greatly improves outcomes.
From The stigma of mental illness is fading in The Economist