We live in a sick world. Just 4 per cent of people had no health problems in 2013, according to a global medical check-up published today in a leading journal.
The Global Burden of Diseases study in The Lancet is based on data from 188 countries and makes estimates for the quantity of health loss from 301 types of disease and injury.
The study found that the number of individuals with more than 10 disorders increased by 52 per cent from 1990 to 2013.
The amount of health loss from diabetes rose by 136 per cent during the 23 years since the first global study. Health loss from alzheimer's disease rose by 92 per cent, medication-overuse headache by 120 per cent and osteoarthritis by 75 per cent.
Health loss, measured as the total number of years lived with disability (YLDs), increased over the period due to population growth and ageing - elderly people are the sickest - but the per-capita rate of YLDs declined slightly to 110, from 115, per thousand people.
In New Zealand, the leading causes of years lived with disability were, in order: back pain, major depression, neck pain, anxiety, other musculoskeletal disorders, asthma, chronic obstructive pulmonary disorder, hearing loss, diabetes, and migraine.
The global ranking of YLDs was: back pain, major depression, iron-deficiency anaemia, neck pain, hearing loss, migraine, diabetes, chronic obstructive pulmonary disorder, anxiety, and other musculoskeletal disorders.
The study has been done every few years since 1990 and the leading causes of health loss globally have changed little since then.
In 2013, musculoskeletal disorders (mainly lower back pain, neck pain and arthritis) and mental and substance-abuse disorders accounted for almost half of all health loss worldwide.
The study's authors note that rates of disability are, overall, declining much more slowly that death rates. They found that while increases in rates of diabetes had been substantial, at around 43 per cent since 1990, death rates from the disease increased by only 9 per cent.
"The fact that mortality is declining faster than non-fatal disease and injury prevalence is further evidence of the importance of paying attention to the rising health loss from these leading causes of disability, and not simply focussing on reducing mortality," said the lead author, Theo Vos, professor of global health at the University of Washington in the United States.
"Large, preventable causes of health loss, particularly serious musculoskeletal disorders and mental and behavioural disorders, have not received the attention that they deserve.
"Addressing these issues will require a shift in health priorities around the world, not just to keep people alive into old age, but also to keep them healthy."