50-year mortality trends in children and young people: a study of 50 low-income, middle-income, and high-income countries

Summary Background Global attention has focused on mortality in children younger than 5 years. We analysed global mortality data for people aged 1–24 years across a 50-year period. Methods The WHO mortality database was used to obtain mortality data from 1955 to 2004, by age-group (1–4, 5–9, 10–14, 15–19, and 20–24 years) and stratified by sex. To analyse change in mortality, we calculated mortality rates averaged over three 5-year periods (1955–59, 1978–82, and 2000–04) to investigate trends in deaths caused by communicable and non-communicable diseases and injury. Findings Data were available for 50 countries (ten high income, 22 middle income, eight low income, seven very low income, and three unclassified), grouped as Organisation for Economic Co-operation and Development (OECD) countries, Central and South American countries, eastern European countries and ex-Soviet states, and other countries. In 1955, mortality was highest in the 1–4-year age-group. Across the study period, all-cause mortality reduced by 85–93% in children aged 1–4 years, 80–87% in children aged 5–9 years, and 68–78% in young people aged 10–14 years in OECD, Central and South American, and other countries. Smaller declines (41–48%) were recorded in young men (15–24 years), and by 2000–04, mortality in this group was two-to-three times higher than that in young boys (1–4 years). Mortality in young women (15–24 years) was equal to that of young girls (1–4 years) from 2000 onwards. Substantial declines in death caused by communicable diseases were seen in all age-groups and regions, although communicable and non-communicable diseases remained the main causes of death in children (1–9 years) and young women (10–24 years). Injury was the dominant cause of death in young men (10–24 years) in all regions by the late 1970s. Interpretation Adolescents and young adults have benefited from the epidemiological transition less than children have, with a reversal of traditional mortality patterns over the past 50 years. Future global health targets should include a focus on the health problems of people aged 10–24 years. Funding None.