The world's adolescents -- large unmet needs and growing inequalities

The global study provides the first comprehensive and integrated snapshot of the health and wellbeing of the 1.8 billion adolescents aged 10-24 who make up a third of the world's population.

The research, published in The Lancet, builds on the earlier Lancet Commission of Adolescent Health and wellbeing and was led by the Murdoch Children's Research Institute, the University of Melbourne and the Burnet Institute, in Melbourne, Australia.

The study tracked the progress of adolescent health in 195 countries between 1990 and 2016 against 12 indicators including tobacco use, obesity, anaemia, secondary school education, child marriage, nutrition and non-communicable diseases.

Lead author, Burnet Institute Co-Head of Adolescent Health, Peter Azzopardi, who also holds positions with the Murdoch Children's Research Institute and the University of Melbourne, said the study exposes the failure of health, education and legal systems to keep up with shifting adolescent needs and demographic change.

"While there have been great improvements in adolescent health in some countries, the greatest population growth has been in countries where adolescents experience the largest disease burden. There are now an extra 250 million adolescents living in these settings compared to 25 years ago," Dr Azzopardi said.

"Investments in adolescent health have also not kept pace with needs. For example, compared to 1990, there are now 180 million more adolescents overweight and obese, and 75 million more living with anaemia.

"The absolute number of young people not completing secondary education, 300 million, has changed little since 1990, and there remains substantial gender inequality in post education opportunities, with young women three times more likely to not be in employment or training compared to young men," he said.

Dr Azzopardi said investing in adolescent health provided a "triple dividend" by ensuring the health of adolescents now, in the future, and for their children.

He said the paper, titled 'Progress in adolescent health and wellbeing: tracking 12 headline indicators for 195 countries and territories, 1990-2016', would not only help to inform government policy, but would provide many under-resourced, low and middle-income countries with much needed data to identify priorities for health action.

"Many countries in the Asia Pacific region and Sub-Saharan Africa, where the majority of the world's adolescents live, don't have access to data describing adolescent health needs. This report describes how they are progressing, but also how they compare with the rest of the world," Dr Azzopardi said.

Senior author, University of Melbourne Adolescent Health Professor George Patton of the Murdoch Children's Research Institute, said adolescent health was underfunded and overlooked by many governments.

"Social and digital media, changing diets, urbanisation, armed conflict and migration are some of the forces now shaping adolescent health growth and development, and the world is not keeping up. With a huge rise in the numbers of adolescents growing up in poor countries, the global challenges in adolescent health are now greater than 25 years ago," Professor Patton said.

"Yet we still do not invest in adolescent health: in low-income countries young people make up around 30 per cent of the population but receive less than two per cent of the world's health investments," Professor Patton said.

Dr Azzopardi and Professor Patton said the research reinforced the case for comprehensive and integrated investments in adolescent health, growth, and development.

The paper was funded by Australian National Health and Medical Research Council, and the Bill & Melinda Gates Foundation.

Global snapshot 2016:

The largest population of adolescents ever

• The world is now home to 1.8 billion adolescents, the largest population in human history.
• Population growth has mostly occurred in low and middle-income countries where adolescents experience a heavy and complex burden of disease. More than half of the world's adolescents now live in these settings and carry two thirds of the global disease burden for adolescents.

Disease

• More than half of the total disease burden experienced by adolescents is due to non-communicable diseases (including mental disorders). NCDs are the leading cause of disease for adolescents in every country and this has changed little since 1990.
• A quarter of the total disease burden is due to communicable, maternal and nutritional disease. However almost all of this disease burden is borne by adolescents living in 70 low and middle-income countries.

Substance use

• Tobacco smoking prevalence declined overall, but 136 million adolescents smoked daily in 2016.
• 71 million adolescents reported binge drinking in 2016, a slight increase since 1990.
• Tobacco smoking and binge drinking increased most rapidly among girls in many low and middle-income countries.

Nutrition and obesity

• One in five (324 million) adolescents was overweight or obese in 2016. One in four (430 million) was anaemic.
• Overweight and obesity are increasing rapidly for adolescents across all countries, and yet are not included as a specific focus of the Sustainable Development Goals.

Sexual and reproductive health

• In 2016 there were 12 million live-births to adolescent mothers, almost three-quarters of which occurred in countries where adolescents experience a heavy burden of disease.
• An estimated 66 million girls were married as children before turning 18 (child marriage). Forty per cent of girls in countries with the poorest health profiles were married as children.
• 73 million young women aged 15-24 in 2016 could not access contraception. Injury
• Males carried three quarters of the global disease burden due to injuries in 2016. Education
• 300 million (half) of 20 to 24-year-olds had not completed secondary school in 2016, a figure that has improved little since 1990.
• Although there was gender parity in secondary school completion, young women in low and middle-income countries were five times less likely than boys to be in employment and further training.

Key country findings

Population

• India and China have a third of the world's adolescents. Disease burden
• Lesotho, Central African Republic and Mozambique had the largest burden of communicable, maternal and nutritional disease.
• Syria, Afghanistan, Yemen and Iraq have the largest burden of injuries for adolescents.
• Greenland, Solomon Islands, Vanuatu, Papua New Guinea, Kiribati, and Federated States of Micronesia are among nations with the largest burden of non-communicable diseases.

Substance use

• Indonesia and Papua New Guinea are among countries with the highest prevalence of tobacco smoking for males.
• Binge drinking was most prevalent in Denmark, Finland and Ireland, with overall rates above 50 per cent in Australia.

Nutritional risk

• American Samoa, Tonga, Kuwait and Qatar are amongst countries with the highest rates of obesity.
• India's rate of anaemia in females (54 per cent) is almost twice the global average.
• Just under half of all adolescents with anaemia (194 million) lived in India and China.

Sexual and reproductive health

• Australia ranks highest in satisfying demand for modern contraception, with South Sudan, Somalia and Chad among the lowest.
• Adolescent pregnancy rates are highest in Niger, Mali and Angola (greater than 150 per 1000).
• Niger, Central African Republic, Chad and Bangladesh were among countries with highest rates of child marriage (more than 50 per cent).

Education and employment

• In India 3.5 per cent of males are not in education, employment or training compared to 53.9 per cent of females.
• Secondary school completion rates are highest in Taiwan, South Korea, USA, Croatia, Singapore and Fiji, and lowest in sub-Saharan Africa.