"[D]epression had the largest effect on worsening health compared with the other chronic conditions," such as asthma, angina, asthma, arthritis or diabetes, according to a study conducted by the World Health Organization.Interviewing more than 245,000 people from 60 countries, WHO concludes that people with depression have the lowest overall health scores - made worse when another chronic disease co-occurs. The article is part of a series about global mental health published in the Sept. 8th issue of The Lancet.