Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease [1, 2], but it remains a significant public health problem. It is a major chronic cause of mortality and morbidity and has been identified as the third leading cause of mortality and morbidity worldwide [3–5]. The World Health Organization (WHO) estimated that 274 million people worldwide died of COPD in 2000 [1]. An estimated 43 million men and women in China have COPD [6], and the disease mortality is about 1.6% [7]. Management of patients with COPD must therefore become a priority in China.

COPD is characterized by airflow limitation that is not fully reversible, and a progressive decline in lung function [1]. Patients often exhibit chronic dyspnea and bronchitis, coughing, sputum production, and pathologic features of emphysema. COPD is often accompanied by exacerbation of respiratory symptoms requiring hospitalization [8]. The goals of managing stable COPD include reducing the frequency and severity of exacerbations, as well as controlling baseline symptoms [1, 9, 10].

The management of patients with COPD depends upon their understanding and recognition of the disease [11–13]; they then need to seek out a general practitioner who must also recognize the condition [14]. However, current management of COPD is primarily based on hospitalized cases in urban districts [15, 16], and little attention has been paid to community-based cases in other areas.

Vulnerability refers to the susceptibility of a population to risks, reflected in the likelihood and extent of population health losses caused by certain factors or changes to the health-care system [17]. Vulnerability can influence people’s competence, increase their susceptibility to disease, and prolong recovery [18]. The cognitive vulnerability of COPD patients is affected by personal factors, social environment, medical history, and many other factors. Personal factors include a lack of knowledge of methods for the prevention and control of COPD, poor lifestyle, attitude, and high-risk behaviors. The social environment includes social support, availability of information, health care, economic aspects, and other factors. To evaluate the vulnerability of a population, it is necessary to identify the factors that lead to these aspects of vulnerability. Studies of the extent of cognitive vulnerability in patients with COPD can provide a scientific basis for developing targeted control measures.

This study therefore aimed to evaluate the vulnerability of patients with COPD, with respect to their comprehension of the disease, treatments and economic burdens, and to provide scientific evidence to improve the prevention and management of COPD in China and other countries.

This is the first study to investigate the vulnerabilities caused by COPD in China. The results indicated high cognitive vulnerability of COPD patients in rural areas of Xuzhou. Although health education is the most effective means of improving symptoms in patients with COPD [25], no health education programs were implemented in the current survey region. Most of the patients (96.4%) in the current study had never heard the term ‘COPD’ before, which was fewer than reported by Walker et al.[26]. Lung function tests and health education programs were not implemented in these patients either. These results were also consistent with the findings published by Ning et al.[27]. Tobacco smoking is the best-known causal factor associated with the development of COPD, and cessation of smoking is the only measure that can prevent the disease and modify its clinical course [28]; however, our results showed that 32.1% of patients did not know that smoking was the main risk factor for COPD. The health education system thus needs to be improved in order to raise the awareness of patients to COPD.

Medication can effectively prevent and control the symptoms of COPD, reduce the frequency and severity of exacerbations, and improve both exercise tolerance and quality of life [29, 30]. Optimizing management of COPD patients, especially stable patients, can reduce the frequency of acute episodes [31]. Our survey showed that patients in rural Xuzhou were highly vulnerable to poor disease management. None of the stable patients received regular drug treatment, and the drug-regimen-compliance rate was significantly lower than that reported by Barr et al.[32]. No individuals used inhalers or spray treatments during the acute exacerbation stage of COPD, which is well below the normal rate of inhaler use of approximately 10%, reported by Restrepo et al.[33]. There has been a recent increase in interest in pulmonary rehabilitation programs, in line with clinical evidence clearly demonstrating reduced dyspnea, increased exercise tolerance, improved physical and emotional participation, and decreased health-care costs [34]. The current results showed that none of the patients in rural Xuzhou understood how to perform rehabilitation exercises. Influenza vaccination has been shown to prevent acute respiratory infections in patients with all severities of COPD [35], and influenza and pneumococcal vaccinations are recommended as an important risk-reduction strategy [36]. Additionally, mainly for financial reasons, patients in the current study were only hospitalized in rural hospitals, which did not provide health education.

The yearly per capita net income of Tongshan rural farmers in 2008 was 6,340 yuan, or 528 yuan per month, but the monthly per capita net income of COPD patients was 34.1% lower. The average annual income of COPD patients’ families was 3,600 yuan, which was 43.2% lower than that of rural farmers. In addition, COPD patients experienced an annual direct economic burden of 1,090 yuan as a result of medical expenses, accounting for one third of their families’ incomes. COPD caused a potential loss of 3.25 years of life per patient, which was higher than that reported by Fei et al.[36]. The indirect loss of income was calculated to be as high as 20,605 yuan per capita, indicating that COPD had a detrimental effect on the local population. In addition to more measurable losses, many patients lost their ability to work. This direct economic burden was less than that reported for developed countries, such as Spain, the United States and many European countries [37, 38]. However, the annual per-capita income in these countries is also much higher than in rural China, and the COPD patients in this study might thus suffer a larger direct economic burden than patients in the U.S. and Europe.

This study was limited by focusing primarily on farmers, who do not have fixed working hours. This made it difficult to calculate accurately the number of working days lost as a result of disease. Patients also lacked formal treatment, and it was therefore difficult to obtain reliable information on medical economics.

Patients with COPD experienced greater cognitive vulnerability, poorer disease management, and greater disease burden than healthy people. Interventions are needed to improve the prevention and management of COPD. Further studies are needed to verify these findings.