Prevalence of passive smoking in the community population aged 15 years and older in China: a systematic review and meta-analysis

OBJECTIVES: To estimate the prevalence and distribution of passive smoking in the community population aged 15 years and older in China. DESIGN: A systematic review and meta-analysis of cross-sectional studies reporting the prevalence of passive smoking in China and a series of subgroup, trend and sensitivity analyses were conducted in this study. DATA SOURCE: The systematic review and meta-analysis, which included 46 studies with 381 580 non-smokers, estimated the prevalence and distribution of passive smoking in China. All studies were published between 1997 and 2015. RESULTS: The pooled prevalence of passive smoking was 48.7% (95% CI 44.8% to 52.5%) and was relatively stable from 1995 to 2013. The prevalence in the subgroups of gender, area, age and time varied from 35.1% (95% CI 31.8% to 38.3%) in the elderly (≥60 years) to 48.6% (95% CI 42.9% to 54.2%) in urban areas. The prevalence was lower in the elderly (≥60 years) than in those between 15 and 59 years of age (OR 1.61, 95% CI 1.44 to 1.81). The difference between females and males in urban and rural areas was not statistically significant (OR: 1.27, 95% CI 0.93 to 1.74 and OR: 1.14, 95% CI 0.82 to 1.58, respectively). In addition, a significantly increasing trend was found among males from 2002 to 2010. Heterogeneity was high in all pooled estimates (I(2)>98%, p<0.001). CONCLUSIONS: The high and stable prevalence of passive smoking in China is raising increasing national concern regarding specific research and tobacco control programmes. Attention should be focused on young, middle-aged and male non-smokers regardless of region.