Smoking, cessation and expenditure in low income Chinese: cross sectional survey

Although smoking prevalence is decreasing in most countries, there is a widening gap in smoking prevalence between socioeconomic groups: the poor and less well-educated are now more likely to smoke, they smoke more cigarettes and are less likely to quit than the wealthier and better educated [1, 2]. In China only very recently has evidence for such a gap started to emerge [3, 4]. China makes a huge contribution to the global burden of disease from tobacco[5]. It is the largest producer and consumer of cigarettes in the world and home to more smokers than in all developed countries combined [6, 7]. Few Chinese women smoke, but with a smoking prevalence in men of around 60% [8‐11] it is estimated that around one third of all Chinese men will die prematurely of a smoking-related disorder [12, 13].

With disproportionate numbers of smokers coming from low income groups this raises specific concerns. Not only do the costs of smoking represent a higher proportion of income for poor smokers, but the overwhelming majority of the poor are uninsured and rely on out-of-pocket payments for healthcare, so that expenditure on cigarettes may also have opportunity costs for access to healthcare [14]. This clearly has implications for the health of poor smokers and their families. Smokers themselves are therefore doubly vulnerable to ill-health.

To control tobacco consumption in China is a massive public health challenge and there is increasing awareness that tobacco control measures should particularly target low income groups. This study was carried out to help inform tobacco control measures and to provide baseline measures for interventions in the eastern province of Zhejiang. It aimed to quantify and explore smoking behaviours, knowledge and expenditure in three distinct unskilled low income groups: urban workers, rural peasants and rural-urban migrants. While there are studies of smoking prevalence in rural populations [4, 9] there is little information about migrant workers and poor urban populations[11]. Migrant workers are of particular interest because of their large and increasing numbers: 120 million across the country in 2000, with predictions of 160 million or 25% of the working population by 2010[15]. They are also thought to have high levels of stress, resulting from loss of accustomed social networks, insecurity, poor living conditions, and marginalisation in urban communities[16]. In other populations this has been shown to lead to a greater tendency to risk behaviours, including smoking [17].

The study was carried-out from June to December 2004 in Hangzhou, the provincial capital, and two rural townships in Zhejiang Province. Hangzhou has a population of 6.2 million with a migrant population of around one million, and is one of the boom cities of the East [18]. The study was carried-out in two of the eight districts of the city, randomly selected to represent suburban (Xiaoshan) and inner-city (Xihu). In each district a list of workunits employing at least 30 workers and providing unskilled employment for both migrants and local people was drawn-up, giving 31 in Xiaoshan and 42 in Xihu. A sample of 50% of these workunits was selected to be representative of the major occupations of migrant workers in Hangzhou. For example, in Xihu 16 of 28 workunits were involved in manufacturing so, the first eight factories on the list drawn-up were approached. In total sixteen workunits in Xiaoshan and 21 in Xihu were asked to participate and none refused. Migrants were defined as individuals who hold rural household registration (hukou) and who had been working in Hangzhou for at least three months and up to ten years. In China by law individuals must hold a hukou, which ensures certain citizen's rights, including access to education and health care, in the place where the hukou is held. With very few exceptions the household registration stays at the point of departure and so migrants are classified as temporary, irrespective of their length of stay and most eventually return to their rural area [19]. In each workunit all workers (migrant and urban) present on the day were recruited into the study. This led to an almost 3 to 2 ratio of migrants to urban workers.

Rural sampling took place after the migrant data were obtained, since the aim was to include areas from which a large number of the migrants originated. Migrants originated from 27 of the 33 Chinese provinces By far the largest single group (21%) were from Western Zhejiang, so this area was selected to provide the rural sample. Two of the 12 counties in Western Zhejiang were randomly selected and three villages in each of the counties were in turn randomly selected. Households were then randomly sampled from lists held by village authorities to achieve a sample size of approximately 300 respondents per village or a total of 1800. Working adults aged 15 to 52 (to match the age range in the migrant and urban samples) resident in the selected households on the day of the survey were included.

Respondents completed a questionnaire, developed specifically for the study and which included open and closed questions covering:

1)socio-demographic characteristics, 2) lifestyles, including income, 3) smoking knowledge, behaviours and expenditure. Key questions on smoking behaviour were drawn from those used in the national survey of 1996 [20], but additional questions were added to explore smoking behaviour and in particular smoking cessation in more depth. The questionnaire was piloted among a representative sample of 50 respondents across the three groups and was amended prior to finalisation. Questionnaires were completed in the respective workunits in Hangzhou and in respondents' homes in the villages. In both settings questionnaires were completed in the same way, self-administered without conferring with colleagues or family members. But research assistants were on-hand to help with any queries.

Anonymity and confidentiality were assured. Approvals for the study were obtained from the Ethics Committee of the Institute of Child Health, University College London and Zhejiang Bureau of Public Health.

The study highlights a number of important issues which have relevance for tobacco control measures. First, the prevalence of smoking in an important group of Chinese men remains high. Interpretation of trends is hampered by differing definitions of current smoking across studies and the different population groups studied but some trends do emerge. Data from the 1996 national prevalence study [20] classified 67% of Zhejiang men as current smokers, (using the same definition as ours) compared with our estimate of 54%. Two recent smaller studies carried-out in Hangzhou residents found rates for smoking among adult males to be 47% [22] and 43% [23] respectively. Clearly direct comparison between these studies is hampered by different definitions of current smoking, different samples used and the fact that we sampled only in low-income workers who would be expected to smoke more. Given that these figures seem to be consistently lower across more recent studies indicates that smoking prevalence in male Chinese may be decreasing and at the very least is not on the increase. This would concur with findings from other studies. Cheng found 57% of Chinese male peasants across five provinces were current smokers, which was described as lower than had been reported previously[4], and Yang found a 1.8% reduction in ever smoking between 1996 and 2002 in men across 145 sentinel surveillance sites[3]. Trends across age cohorts in our study also tend to support this view. The low prevalence of smoking in the under 20 cohort relates largely to late uptake, as illustrated by responses to the direct question about age of onset of smoking and which is has been shown in other studies. [9, 20, 24]. But for the other three age groups there is an upward trend in smoking prevalence, which is more marked for moderate and heavy smoking. This suggests that younger age groups are taking-up smoking less or are quitting more. Since relatively small numbers have quit the former is a more plausible explanation.

Our a priori hypothesis that migrants would be heavy smokers and would warrant intensive tobacco control measures has been refuted: migrants take up smoking later, are least likely to become regular or heavy smokers, and are more likely to want to quit, and to be successful when they do. Another study in rural-urban migrants in Beijing reported male current smoking prevalence of 52%, though there were no comparison groups [25]. These lower than expected figures may relate in part to the fact that migrants leave home in the first place in order to make money [15] and so are highly motivated to cut down or quit smoking in order to save more money to take back to their rural communities.

More worrying are the high rates of heavy smoking, especially in the rural population, where nearly half the men (49%) smoked more than 10 cigarettes per day and 22% smoked more than 20 cigarettes per day suggesting that the burden of disease attributable to smoking in eastern rural China is huge. Given that the rural dwellers are the poorest group and access to healthcare is compromised by high expenditures on cigarettes, it is clear that tobacco control measures should do far more to target rural populations.

There is also an indication that numbers of quitters, though small, may be on the increase. The 1996 study reported 3.5% successful and 15% intending quitters in Zhejiang [19] compared with 7% and 22% respectively in our study. Again it must be noted that comparison is hampered by the different samples for the two studies. However, this does suggest that quitting may be on the increase. In a recent Hangzhou-based study of male smokers 22% claimed to have tried to quit, though quitting was not clearly defined [22]. In this study social stigma was given as one of the reasons for wanting to quit by one quarter of the sample. In our study no-one gave social stigma as a reason, suggesting that at least among low income groups smoking is not stigmatised and indicating that health promotion measures should perhaps focus on trying to make smoking less socially acceptable. The data on quitting has important implications for tobacco control measures. With 22% of men stating their intention to quit and most acknowledging how difficult quitting is, support should be made available for them. There is good evidence from a number of countries that nicotine replacement therapy (patches, gum etc) can increase success rates [26]. These therapies were virtually unknown to the respondents in this study, but they could be produced cheaply and be made widely available. Again it was noted that workplace bans had helped some of those who had quit, suggesting that bans on smoking in workplaces and public places should be broadened and enforced. In Zhejiang enforcement measures especially in the workplace have been weak. It was also notable that we found that where smoking was permitted, in the agricultural and construction sectors, there were particularly high rates of heavy smoking, compared with those workunits where there are restrictions such as in factories, shops and hotels Smoking restrictions elsewhere have been shown to help both with quitting and with reducing numbers of cigarettes smoked [27, 9].

We show that expenditure on smoking constitutes a large proportion of personal income, an average of 11%, but rising to 15.4% for rural inhabitants. The opportunity costs are considerable with disproportionate effects in poor rural households, including compromising access to healthcare. Other studies have calculated expenditure on smoking as a percentage of household income, producing lower estimates, because there is usually one smoker per couple [30]. The findings indicate that information about the opportunity costs of smoking could be used in health promotion messages, to discourage youngsters from starting and to promote cessation efforts. Our findings on expenditure also raise questions about the role of tobacco taxation as deterrent in low income groups. In 1997 tobacco taxation accounted for 11% of all central government revenue [31]. The cost of cigarettes varies from $0.5 to around $8 per pack in China, of which around 40% is tax [32]. With such cheap cigarettes available cost clearly becomes less of a deterrent. This is shown in our study by the finding that the heaviest smokers were the poor rural inhabitants; the poor just smoke cheaper cigarettes. But price elasticity for cigarettes (the reduction in consumption which follows an increase in unit price) in China has been a matter for debate [32, 33], and it is not clear to what degree individuals would reduce their consumption if prices were to rise, and whether increased taxation would simply disproportionately punish the poor, given evidence that the poor are less likely to quit than the wealthier [1, 2]. This is one of the reasons the Chinese government has given for not using tougher fiscal measures [34].

Knowledge of the health risks of smoking was generally good, while knowledge of the dangers of passive smoking was poor. This is of particular concern given the finding that married and having children were positively associated with moderate and heavy smoking. Campaigns to raise awareness of the dangers of passive smoking should be incorporated into health promotion programmes.

The study has a number of limitations. First, this study was carried-out in low income working individuals in a rich eastern coastal province. While some inferences can be drawn from this sample to individuals of similar socioeconomic status in other coastal provinces, our sample does not try to be representative of other parts of China, especially the poor inland and Western provinces. Second, the study sampled workunits in the formal sector and did not include the self-employed, such as hawkers and street-traders, but it is estimated that these account for less than 5% of migrants in Hangzhou, so our sample is representative of the overwhelming majority. Third, the validity of self-report may be questionable, perhaps more so among groups for whom smoking may be less acceptable, such as women. It is also possible that the different situations in which the questionnaires were completed, workunits in the urban area and home in the rural area could present a source of bias. Fourth, comparisons of personal income across the three groups are crude, because of different purchasing power and lifestyle in rural areas. Finally, exploratory questions were only asked of moderate and heavy smokers, because they are most likely to incur opportunity costs, but this may limit the applicability of this section of the results.

The results of this study have provided important pointers for tobacco control measures. Given the high rates of smoking among rural workers, these populations need to be specifically targeted for tobacco control measures. Up until now health promotion efforts in Zhejiang and other Chinese provinces have focused on urban areas with very limited (if any) activity in rural areas. Smoking restrictions in workplaces and public places should be widened and enforced. At present these are piecemeal and often not enforced. Support should be provided to smokers who want to quit and cheap aids to quitting should be made available. Although health education messages have had disappointing results in many countries [35] our study highlights areas which might serve as foci for health promotion messages: the dangers of passive smoking, the opportunity costs of smoking and making smoking less socially acceptable. In September 2005 China ratified the Framework Convention on Tobacco Control. This has created new impetus for tobacco control measures. This together with somewhat encouraging trends in prevalence and quitting, indicate that China may see further declines in smoking in the near future.