RESUMEN
OBJECTIVE: To investigate if socioeconomic gradients in health reduce during adolescence (the equalisation hypothesis) in four low-income and middle-income countries (LMIC). SETTING: Analysis of the Young Lives Study cohorts in Ethiopia, Peru, Vietnam and India. PARTICIPANTS: A total of 3395 participants (across the four cohorts) aged 6-10 years at enrolment and followed up for 11 years. OUTCOMES MEASURED: Change in income-related health inequalities from mid-childhood to late adolescence. Socioeconomic status was determined by wealth index quartile. The health indicators included were self-reported health, injuries in the previous 4 years, presence of long-term health problems, low mood, alcohol use, overweight/obesity, thinness and stunting. The relative risk of each adverse health outcome between highest and lowest wealth index quartile were compared across four waves of the study within each country. RESULTS: We found steep socioeconomic gradients across multiple health indicators in all four countries. Socioeconomic gradients remained similar across all waves of the study, with no significant decrease during adolescence. CONCLUSION: We found no consistent evidence of equalisation for income-related health inequalities in youth in these LMIC. Socioeconomic gradients for health in these cohorts appear to persist and be equally damaging across the early life course and during adolescence.
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Países en Desarrollo , Equidad en Salud , Disparidades en el Estado de Salud , Indicadores de Salud , Adolescente , Consumo de Bebidas Alcohólicas/epidemiología , Niño , Enfermedad Crónica , Depresión/epidemiología , Etiopía/epidemiología , Trastornos del Crecimiento/epidemiología , Estado de Salud , Humanos , Renta , India/epidemiología , Obesidad/epidemiología , Perú/epidemiología , Clase Social , Delgadez/epidemiología , Vietnam/epidemiología , Heridas y Lesiones/epidemiología , Adulto JovenRESUMEN
INTRODUCTION: Life-course studies are needed to explore how exposures during adolescence, particularly puberty, contribute to later cardiovascular risk and cognitive health in low and middle-income countries (LMIC), where 90% of the world's young people live. The extent of any existing cohorts investigating these outcomes in LMIC has not previously been described. METHODS: We performed a systematic literature review to identify population cohort studies of adolescents in LMIC that assessed anthropometry and any of cardiovascular risk (blood pressure, physical activity, plasma glucose/lipid profile and substance misuse), puberty (age at menarche, Tanner staging, or other form of pubertal staging) or cognitive outcomes. Studies that recruited participants on the basis of a pre-existing condition or involved less than 500 young people were excluded. FINDINGS: 1829 studies were identified, and 24 cohorts fulfilled inclusion criteria based in Asia (10), Africa (6) and South / Central America (8). 14 (58%) of cohorts identified were based in one of four countries; India, Brazil, Vietnam or Ethiopia. Only 2 cohorts included a comprehensive cardiovascular assessment, tanner pubertal staging, and cognitive outcomes. CONCLUSION: Improved utilisation of existing datasets and additional cohort studies of adolescents in LMIC that collect contemporaneous measures of growth, cognition, cardiovascular risk and pubertal development are needed to better understand how this period of the life course influences future non-communicable disease morbidity and cognitive outcomes.
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Enfermedades Cardiovasculares/epidemiología , Fenómenos Fisiológicos Cardiovasculares , Trastornos del Conocimiento/epidemiología , Cognición , Crecimiento , Adolescente , Brasil/epidemiología , Estudios de Cohortes , Etiopía/epidemiología , Femenino , Humanos , India/epidemiología , Masculino , Pubertad , Vietnam/epidemiologíaRESUMEN
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.
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Países Desarrollados/estadística & datos numéricos , Países en Desarrollo/estadística & datos numéricos , Mortalidad/tendencias , Adolescente , Distribución por Edad , Causas de Muerte , América Central/epidemiología , Niño , Preescolar , Enfermedades Transmisibles/mortalidad , Países Desarrollados/economía , Países en Desarrollo/economía , Europa Oriental/epidemiología , Femenino , Salud Global , Humanos , Lactante , Masculino , Estudios Retrospectivos , Distribución por Sexo , América del Sur/epidemiología , Heridas y Lesiones/mortalidad , Adulto JovenRESUMEN
OBJECTIVES: To examine the effects of duration, timing and type of television (TV) viewing at age 5 years on body mass index (BMI) in adult life. STUDY DESIGN AND METHODS: 1970 British Birth Cohort, followed up at 5 (N=13,135), 10 (N=14,875), and 30 years (N=11,261). OUTCOME MEASURES: Weekday and weekend TV viewing at 5 years, type of programs, and maternal attitudes toward TV at age 5 years. BMI z-score at 10 and 30 years. RESULTS: Mean daily hours of TV viewed at weekends predicted higher BMI z-score at 30 years (coefficient=0.03, 95% CI: 0.01, 0.05, P=.01) when adjusted for TV viewing and activity level at 10 years, sex, socioeconomic status, parental BMIs, and birth weight. Each additional hour of TV watched on weekends at 5 years increased risk of adult obesity (BMI > or =30 kg/m2) by 7% (OR=1.07, 95% CI 1.01, 1.13, P=.02). Weekday viewing, type of program and maternal attitudes to TV at 5 years were not independently associated with adult BMI z-score. CONCLUSIONS: Weekend TV viewing in early childhood continues to influence BMI in adulthood. Interventions to influence obesity by reducing sedentary behaviors must begin in early childhood. Interventions focusing on weekend TV viewing may be particularly effective.