Socioeconomic disparities in prevalence and behaviors of smoking in rural Southwest China

Tobacco smoking causes many preventable diseases and its impact on premature death is a major concern worldwide: the World Health Organization (WHO) reports that smoking accounts for almost 6 million deaths globally each year [1]. China is both the world’s largest tobacco manufacturer and consumer, accounting for one-third of the world’s tobacco production and consumption [2]; it is home to 300 million smokers and 740 million non-smokers exposed to secondhand smoke [3, 4]. In turn, China has experienced a large-scale increase of smoking-related chronic disease, creating an immense public health challenge and, consequently, a significant financial burden, especially in rural communities [5]. The serious dangers that smoking poses to health are evident. Yet, implementing effective tobacco control programs has been challenging, particularly in rural, tobacco cultivating regions.

Growing evidence both in developed and developing countries suggests that smoking behaviors are associated with socioeconomic status (SES). Those with less education and lower incomes are more likely to smoke [6‐8]. Prior research also indicates that early smoking initiation is negatively correlated with educational attainment, and people with low SES status and lower incomes are less likely to be successful when they attempt to quit smoking [9‐11]. In China, several studies have investigated the relationship between patterns of smoking and SES factors [5, 12], revealing an inverse relationship between education and smoking. Higher educational attainment was also associated with lower likelihood of smoking behaviors among the elderly population in China [13]. China is a multi-ethnic country with 56 state-recognized ethnicities. The Han ethnicity makes up the majority of the population (> 92%) while the remaining 55 ethnic groups are classified as national minorities. Seventy percent of China’s population lives in the countryside. However, due to a lack of research detailing the relationship between individual socioeconomic factors and smoking behaviors, socioeconomic disparities in smoking initiation, quit attempts, and level of tobacco consumption remain poorly understood, particularly in rural populations and ethnic minority groups, the subgroups with the highest prevalence of tobacco use in China [14]. Due to the fact that SES factors are an important determinant of smoking behaviors, a better understanding of SES determinants of prevalence and behaviors of smoking is vital for facilitating the implementation of tailored tobacco control and prevention programs in China. Thus, research that can detail socioeconomic disparities in smoking behaviors holds particular importance.

The aim of this study is to address this research gap by uncovering how prevalence and behaviors of smoking– including current smoking status, level of daily smoking, age of smoking initiation, age of regular smoking, quit attempts, and location of smoking behaviors— differ across socioeconomic groups among southwest China’s rural adult population.

A total of 8100 individuals aged ≥35 years were invited to participate in the study. Of these, 7743 agreed to participate (a response rate of 95.6%).

Demographic characteristics of the participants are summarized in Table 1. In total, 3832 males (49.5%) and 3911 females (50.5%) participated. The percentage of ethnic minority participants was 39.7%, and illiterate rate was 21.8%. Male participants had higher SES status, higher education levels, household assets, and access to medical services than female participants (P < 0.05).

Table 2 shows the age-standardized prevalence of current smokers by age, sex, and ethnicity among the study participants. The overall prevalence rate of current smokers was 33.5% (62.6% for males, and 4.8% for females). Males had significantly higher prevalence of current smokers than females (P < 0.01). Prevalence of current smokers decreased with age, peaking at 35.3% in the total population aged 35–44 years. The ethnic minority population had a higher prevalence of current smokers than the Han majority population, both for males and females (P < 0.01).

Table 3 presents smoking behaviors by ethnicity among current smokers. Filtered cigarettes were the most popular method of smoking tobacco, comprising over 75.0% of all types of tobacco consumed. 74.5% of current smokers began smoking during adolescence, with 20.1% of smokers reporting regular smoking during adolescence. In the 12 months prior to the survey, most tobacco users (88.8%) had made no attempt to quit smoking. 73.6% of smokers reported having smoked in public places in the 7 days prior to the survey.

There were significant differences in smoking behaviors by ethnicity. After filtered cigarette smoking, hookah/water pipes were the second most popular form of tobacco consumption in the Han majority population, followed by unfiltered cigarettes. In contrast, chewing tobacco was the second most popular form of tobacco consumption in the ethnic minority population, followed by hand-rolled cigarettes. Compared to the Han majority population, ethnic minorities had both a higher proportion of smokers who initiated smoking during adolescence as well as a higher proportion of smokers who regularly smoked during adolescence (P < 0.01). Among current smokers, whereas the prevalence of smoking more than 10 cigarettes daily was higher in the Han majority population than in the ethnic minority population (P < 0.05), ethnic minorities had a higher proportion of smokers who had never attempted to quit smoking and a higher proportion of smokers who smoked in public places than the Han majority (P < 0.01).

Table 4 indicates the results of multivariate logistic regression analysis of prevalence and behaviors of smoking by individual SES after adjusting for age, sex, ethnicity, and current drinking status. Individuals with lower levels of education, poor access to medical services, and lower SEP were more likely to consume tobacco, whereas current smokers with rich household assets and a higher SEP had a higher risk of smoking more than 10 cigarettes daily. Individuals with low education levels and low SEP were more likely to initiate smoking and regularly smoke during adolescence. Among current smokers, access to medical services and SEP were positively associated with the probability of having attempted to quit smoking at least once. Current smokers with higher levels of education and higher SEP had a lower probability of smoking in public places.

This cross-sectional study reveals a high prevalence rate of current smokers, a high prevalence of smoking initiation during adolescence, and a low rate of attempts to quit smoking in rural southwest China. This study also demonstrates that there are significant relationships between SES variables and prevalence and behaviors of smoking.

In this study, the prevalence of current smoking in both sexes (male 62.6%, female 4.8%) was higher than the prevalence rate observed in urban Chinese populations (male 58.4%, female 3.4%) [17] as well as that observed in other Asian countries [4, 18]. However, the rate of smokers who had previously attempted to quit smoking (11.2%) was much lower than reported by the 2010 National China Smoking Survey (17.3%) and that in other Asian countries (59.9%) [19]. Furthermore, men had a remarkably higher prevalence of smoking than women. Such sex differences in smoking are well recognized worldwide: studies in Asia (including China) and Western countries have established many more men than women smoke [17‐19]. Our findings indicate smoking is especially prevalent among men in rural southwest China, and robust smoking cessation programs are urgently needed in rural communities.

The present study found that ethnic minorities had a higher prevalence of current smokers for both males and females and a much lower rate of quit attempts than their Han counterparts. Furthermore, the rate of smoking in public places was also higher in ethnic minorities than in the Han majority population. This may largely be explained by the higher illiteracy rate in the ethnic minority population (32.0%) compared to the Han majority (14.5%), as lower levels of education have a strong effect on smoking habits [13, 20]. The findings suggest tobacco control interventions are particularly needed in rural minority communities.

Several previous Chinese studies indicate that smoking is a serious problem among Chinese teenagers [14, 21]. Our study is consistent with this prior research, finding that 74.5% of smokers began smoking during adolescence. Moreover, ethnic minorities had an earlier age of smoking initiation and of regular smoking than their Han counterparts. These findings underscore an urgent need to strengthen adolescent tobacco control programs, particularly among ethnic minorities in rural China.

In China, traditions, heritage, culture, and lifestyles differ by ethnic group. Previous studies indicated that there are pronounced ethnic variations in prevalence of smoking and form of tobacco use. This possibly results from the strong collective social life in many ethnic minority communities, as well as differing cultures and shared environmental influences related to smoking behaviors [16, 22, 23]. Our study found that filtered cigarettes were the most popular form of tobacco used in rural southwest China, a finding consistent with previous Chinese studies [14]. However, chewing tobacco was also common among ethnic minorities. Our findings thus demonstrate that ethnicity plays an important role in shaping smoking habits, and culturally appropriate tobacco control interventions could help reduce tobacco product consumption in rural China.

Some previous Chinese studies indicated that public places have the highest secondhand smoke exposure in China [5, 24]. In the present study, the rate of smoking in public places (73.6%) was much higher than found in a previous Chinese study examining 21 Chinese cities (41.2%) [24]. Moreover, individuals with lower levels of education and lower SEP had a higher probability of smoking in public places. These results suggest it is essential to implement smoke-free regulations to protect people from secondhand smoking exposure in rural China, and underscore that efforts to restrict smoking in public places should focus on people with lower education levels and lower SEP.

Lower educational levels are associated with higher risks of smoking [5, 6, 12, 13]. Moreover, prior research has indicated that the highest proportion of smokers in low- and middle-income countries have low SES [25]. Our results are in accordance with these studies. Furthermore, the present study also found that individuals with poor access to medical services are more likely to be current smokers. This is possibly due to the fact that better access to medical services is associated with better access to health related knowledge as well as a higher awareness of tobacco hazards. Thus, our findings suggest that future community-based tobacco control intervention programs need to provide education on the harmful effects of tobacco use, particularly to those with low education levels and low SEP in rural China. They also suggest improved access to healthcare is crucial to controlling smoking.

While several studies from both developing and developed countries have demonstrated that individuals with lower household incomes have a higher risk of smoking [7, 26, 27], our study showed no association between household assets and smoking. This result is in line with a previous Chinese study [13]. However, the present study did find that rich household assets and higher SEP were associated with a higher risk of smoking more than 10 cigarettes daily among current smokers. This possibly results from the fact that smokers with a higher household income and SEP are better able to afford tobacco products. Further investigation is needed to examine the exact nature of the association between income and smoking behaviors.

This study also found that access to medical services was positively associated with the probability of having attempted to quit smoking at least once. This result can possibly be attributed to increased ability to utilize health services and greater knowledge about the harmful effects of tobacco use among these populations. Moreover, higher individual SEP showed a positive association with attempting to quit smoking. A positive relationship between individual SEP and smoking cessation was also observed in a study of a western population [28]. Perhaps those with higher SEP tend to have a healthier lifestyle and therefore consume less tobacco. The findings in this way also indicate that socioeconomic inequality affects behaviors related to smoking cessation.

The following limitations of the present study should be noted. First, smoking behaviors were self-reported, and the lack of validation of smoking status with nicotine testing may underestimate the prevalence of smoking. Second, the present findings were based on a random sampling of three counties, limiting their generalizability.

In conclusion, the present study indicates smoking is serious public health problem posing a major challenge for tobacco control and smoking prevention in rural southwest China, with ethnicity and socioeconomic factors playing an important role in influencing both prevalence and behaviors of smoking. Addressing the socioeconomic determinants of smoking behaviors and providing culturally appropriate tobacco control interventions could help minimize disparities in tobacco use and smoking behaviors and thereby promote public health.