SummaryBackgroundGlobally, a growing number of children and adolescents are left behind when parents migrate. We investigated the effect of parental migration on the health of left behind-children and adolescents in low-income and middle-income countries (LMICs).MethodsFor this systematic review and meta-analysis we searched MEDLINE, Embase, CINAHL, the Cochrane Library, Web of Science, PsychINFO, Global Index Medicus, Scopus, and Popline from inception to April 27, 2017, without language restrictions, for observational studies investigating the effects of parental migration on nutrition, mental health, unintentional injuries, infectious disease, substance use, unprotected sex, early pregnancy, and abuse in left-behind children (aged 0–19 years) in LMICs. We excluded studies in which less than 50% of participants were aged 0–19 years, the mean or median age of participants was more than 19 years, fewer than 50% of parents had migrated for more than 6 months, or the mean or median duration of migration was less than 6 months. We screened studies using systematic review software and extracted summary estimates from published reports independently. The main outcomes were risk and prevalence of health outcomes, including nutrition (stunting, wasting, underweight, overweight and obesity, low birthweight, and anaemia), mental health (depressive disorder, anxiety disorder, conduct disorders, self-harm, and suicide), unintentional injuries, substance use, abuse, and infectious disease. We calculated pooled risk ratios (RRs) and standardised mean differences (SMDs) using random-effects models. This study is registered with PROSPERO, number CRD42017064871.FindingsOur search identified 10 284 records, of which 111 studies were included for analysis, including a total of 264 967 children (n=106 167 left-behind children and adolescents; n=158 800 children and adolescents of non-migrant parents). 91 studies were done in China and focused on effects of internal labour migration. Compared with children of non-migrants, left-behind children had increased risk of depression and higher depression scores (RR 1·52 [95% CI 1·27–1·82]; SMD 0·16 [0·10–0·21]), anxiety (RR 1·85 [1·36–2·53]; SMD 0·18 [0·11–0·26]), suicidal ideation (RR 1·70 [1·28–2·26]), conduct disorder (SMD 0·16 [0·04–0·28]), substance use (RR 1·24 [1·00–1·52]), wasting (RR 1·13 [1·02–1·24]) and stunting (RR 1·12 [1·00–1·26]). No differences were identified between left-behind children and children of non-migrants for other nutrition outcomes, unintentional injury, abuse, or diarrhoea. No studies reported outcomes for other infectious diseases, self-harm, unprotected sex, or early pregnancy. Study quality varied across the included studies, with 43% of studies at high or unclear risk of bias across five or more domains.InterpretationParental migration is detrimental to the health of left-behind children and adolescents, with no evidence of any benefit. Policy makers and health-care professionals need to take action to improve the health of these young people.FundingWellco...

BackgroundPrevious studies have provided inconsistent findings on smoking among migrants, and very limited data exist on their second-hand smoke exposure. This study aims to investigate internal migrants’ smoking prevalence, second-hand smoke exposure among non-smokers, and knowledge of the health hazards of smoking in 12 major migrant provinces in China in 2013.MethodsData from the 2013 Migrant Dynamics Monitoring Survey in China published by the National Commission of Health and Family Planning was used in this study. Descriptive analysis, Chi-square analysis, and sex-stratified multivariate logistic regression analysis were used to explore the determinants of current smoking and second-hand smoke exposure.ResultsAmong 7200 migrants, 34.1% (55% male, 4% female) were current smokers. For males, factors associated with current smoking were education year (aOR = 0.95, 95% CI: 0.93–0.98), duration of stay (aOR = 1.01, 95% CI: 1.00–1.03) and occupation (aOR = 1.25, 95% CI: 1.03–1.53). For females, household registration status (aOR = 1.70, 95% CI: 1.04–2.80) was the most important factor associated with current smoking. Sixty five percent of non-smokers were exposed to second-hand smoke. Factors associated with exposure to second-hand smoke were duration of stay (aOR = 1.01, 95% CI: 1.00–1.02), divorced/widowed marital status (aOR = 0.48, 95% CI: 0.25–0.91), occupation (aOR = 1.29, 95% CI: 1.05–1.58) and the nature of employer (aOR = 0.77, 95% CI: 0.60–0.97). About 95% of participants were aware that lung cancer is one of the hazards of smoking. Non-current smokers had a better knowledge of fertility reduction and accelerated aging as hazards of smoking than current smokers (p < 0.01). Knowledge of the impact of smoking on cardiovascular diseases was relatively low compared with knowledge of other smoking-related hazards (26.1–44.3%).ConclusionsCurrent smoking and exposure to second-hand smoke among internal migrants in China is high. Socio-demographic characteristics and migration status were strongly associated with current smoking and second-hand smoke exposure. We recommend specifically targeted tobacco control interventions to help to address these risk factors, such as focusing on divorced/widowed women.

INTRODUCTIONImplementing comprehensive smoke-free laws is an important part of tobacco control and has been promoted since China ratified the WHO Framework Convention on Tobacco Control (WHO FCTC) in 2005. This study shows the predictors of adopting subnational smoke-free laws and their alignment with Article 8 of WHO FCTC.METHODSThe legislations of 125 cities from China’s top three city grades were assessed, covering the cities that have smoke-free laws. Logistic regression is applied to evaluate the characteristics of cities that adopted a smoke-free law. We also compare each smoke-free law with the WHO FCTC Article 8 requirements.RESULTSProvincial capital cities were more likely to adopt smoke-free laws compared with other cities. Smoke-free laws vary from comprehensive to partial bans with major exemptions. Among the 21 cities that have enacted smoke-free laws, 9 cities prohibited smoking in all indoor workplaces, indoor public places (restaurants, bars, health facilities, government buildings and schools) and public transportation. More than half of the smoke-free laws still allow designated indoor smoking rooms. Smoke-free laws that clearly ban e-cigarettes in smoke-free areas have been implemented in only two cities (Nanning and Hangzhou).CONCLUSIONSThis study shows that a number of Chinese cities have taken legislative measures to protect people from exposure to tobacco smoke. It identifies signs of progress but also areas for improvement, such as the scope of smoke-free laws, imperfect implementation of such laws, and the potential omission of e-cigarettes from the legislation.

ObjectiveTo evaluate a comprehensive tobacco control policy package on hospital admissions for acute myocardial infarction (AMI) and stroke in a global city.DesignInterrupted time series study.SettingBeijing, China.Population31 707 AMI and 128 116 stroke hospital admissions recorded by the Beijing Medical Claim Data for Employees in 17.7 million residents from January 2013 to June 2017.InterventionThe policy package including all components of MPOWER has been implemented since June 2015.Main outcome measuresThe immediate change of AMI and stroke hospital admissions and the annual change in the secular trend.ResultsThere was a secular increase trend for the crude hospital admission rates of AMI and stroke during the observational period. After implementation of the policy, immediate reductions were observed in the hospital admissions for both AMI (−5.4%, 95% CI −10.0% to −0.5%) and stroke (−5.6%, 95% CI −7.8% to −3.3%). In addition, the secular increase trend for stroke was slowed down by −15.3% (95% CI −16.7% to −13.9%) annually. Compared with the hypothetical scenario where the policy had not taken place, an estimated 18 137 (26.7%) stroke hospital admissions had been averted during the 25 months of postpolicy period.ConclusionsThe results indicated significant health benefits on cardiovascular morbidity after the Beijing tobacco control policy package, which highlighted the importance for a comprehensive tobacco control policy at the national level in China. Similar tobacco control policy which consists of all components of MPOWER is urgently needed in other areas, especially in settings with high tobacco consumption, to achieve greater public health gains.