LONDON — The world is caught in a perfect storm of rising rates of chronic disease, persistent infectious diseases and public health failures that have fuelled deaths in the Covid-19 pandemic, according to a major global study of human health.

The emergence and overlap of the coronavirus pandemic with a continued global rise in chronic conditions such as obesity and diabetes — with added environmental risks such as air pollution — have exacerbated the coronavirus death toll, it said.

The Global Burden of Disease study is the most comprehensive of its kind.

Published in The Lancet medical journal, it analysed 286 causes of death, 369 diseases and injuries and 87 risk factors in 204 countries and territories to offer a view on the underlying health of the global population and the impact of Covid-19.

"Covid-19 is an acute-on-chronic health emergency," said Mr Richard Horton, the Lancet's editor-in-chief. He described the coronavirus pandemic combined with high global rates of obesity, diabetes and other chronic diseases as a "syndemic".

The study found that leading causes of ill health in people aged 50 and older worldwide were ischaemic heart disease, stroke, and diabetes. In younger people — aged 10 to 49 — road injuries, HIV/AIDS, lower back pain and depressive disorders were dominant.

It also found that the rise in chronic diseases, combined with a failure of public health to tackle preventable risk factors, had left populations vulnerable to health emergencies such as the coronavirus pandemic.

"The 'syndemic' nature of the threat we face demands that we not only treat each affliction, but also urgently address the underlying social inequalities that shape them," Mr Horton said.

He said chronic conditions such as high blood pressure, high blood sugar, obesity and high cholesterol suffered by millions around the world had played a critical role in driving the more than one million deaths caused by Covid-19 to date.

Such conditions — driven by unhealthy diets and inadequate levels of exercise — "will continue to shape health in every country after the pandemic subsides", he said. REUTERS