The study looked at nearly half a million adolescents from 34 countries across Europe and North America.
Rising national wealth across high-income countries has led to improvements in health and well-being among adolescents, the study notes, but the gap in quality of health between rich and poor has widened.For the study, researchers measured socioeconomic-related inequalities across five distinct areas of adolescent health:
- Physical activity
- Body mass index (BMI)
- Psychological symptoms (such as irritability, feeling low, feeling nervous)
- Physical symptoms (such as headache, stomach ache, backache, feeling dizzy and life satisfaction)
- Difficulty sleeping.
Changes in all of these areas were tracked over the study period of 2002-10. The study looked at nearly half a million adolescents from 34 countries across Europe and North America who were surveyed as part of the World Health Organization (WHO) Behaviour in School-aged Children study in 2002, 2006 and 2010.
The authors also assessed to what extent inequalities in health between socioeconomic groups correlated with national wealth and inequality of income. In the study, socioeconomic status was measured using material assets and "common indicators of wealth," such as owning a car.
Nearly all health areas displayed widening inequalities across study period
Across the study period, the researchers found that the difference in the amount of physical activity between the poorest and richest groups expanded from 0.79 days per week to 0.83 days per week. Using a points system, the researchers measured other increases in differences between poorest and richest, including:
- BMI (0.15 point difference between poorest and richest in 2002, increased to 0.18 in 2010)
- Psychological symptoms (0.58 increased to 0.67)
- Physical symptoms (0.21 increased to 0.26).
The study found only one health factor in which inequality declined - life satisfaction. The points difference for life satisfaction changed from 0.98 in 2002 to 0.95 in 2010.
Adolescents in countries with greater income inequality were reported to be less physically active, have a larger BMI and lower life satisfaction. Adolescents in these countries also reported more psychological and physical symptoms.
The study concludes that greater income inequality correlated with larger health inequalities between socioeconomic groups when it came to psychological and physical symptoms and life satisfaction.
Widening adolescent health inequality is 'cause for alarm'
"A strong international focus on reducing child poverty and mortality in children under 5 years has not been matched by a similar response in older age groups, resulting in widening socioeconomic inequalities in adolescent health," explains Frank Elgar, lead author and a psychiatry professor at McGill University in Quebec, Canada
Prof. Elgar says it is alarming that health inequalities are widening in such abundantly rich countries, particularly during the "healthy years" of adolescence:
"The many health and social problems that relate to income inequality and the current global trends in rising income inequality all lead to a grim prediction about future population health. Urgent action is needed to tackle inequities in health in adolescence."
In 2013, Medical News Today reported on a study published in The BMJ that found income inequality is linked to a greater risk of readmission to hospital.