This was disclosed by data presented last week at the 97th International Conference of the American Thoracic Society. COPD is defined by a leading group of experts from the Global Obstructive Lung Disease (GOLD) initiative as "a disease characterized by airflow limitation that is not fully reversible." The most common symptoms are shortness of breath, cough, wheezing and increased sputum production. COPD symptoms are generally progressive over time, leading to disability and early death.
COPD is among the top five causes of disability and death in industrial countries. In its annual World Health Report, the WHO reported that 600 million people suffer from COPD and approximately three million die in the US, exceeded only by heart attacks, cancer and stroke. The main cause of COPD is smoking.
In the past, it was believed that Asians are less susceptible to COPD than other nationalities. The World Health Organization (WHO) suggested that average COPD prevalence in the Asia-Pacific region would be approximately 3.9 percent. But there has been very little data projecting the overall prevalence of the disease.
A prevalence study was then conducted in 12 Asian countries using the COPD Prevalence Model. It was a validated, computerized tool that evaluates epidemiologic relationships and risk factor prevalence to project the prevalence of the disease.
The results correlated with the presence of risk factors in each country, which included high levels of smoking and exposure to biomass fuels and air pollution. A range of prevalence levels was highlighted across the countries.
For example, Singapore, which has a low smoking prevalence (15 percent), also has a low prevalence of COPD at 3.5 percent. Countries with higher levels of smoking, such as the Philippines with smoking prevalence of 53 percent among men, has a much higher COPD prevalence at 6.3 percent.
Rural areas with exposure to biomass fuels also has higher levels of COPD. Countries like China and Vietnam, where the rural population forms about 60 to 70 percent of the total population, the prevalence of COPD are also high at 6.7 percent and 6.2 percent, respectively.
Prof. Wan-Cheng Tan, chairman of the Asia-Pacific COPD Roundable, who coordinated this study, commented: "I was surprised by the model projections of COPD prevalence in the Asia-Pacific region. The higher than expected prevalence implies that the burden of disease is substantial and a potential drain on healthcare resources if COPD is not recognized early and managed properly.
The report highlights the need to further epidemiology studies to support appropriate allocation of resources and ensure raised awareness of the disease and the risk factors. Prof. Paul Seale from the Asia-Pacific COPD Roundable said that COPD is seriously undermanaged. "We must recognize it at an earlier stage than we currently do. We must develop more effective strategies for smoking cessation and we must ensure that we give our patients the best symptomatic treatment with bronchodilators."
The roundable also hoped that the prevalence data will help prioritize the disease within public health strategies and highlight the need for strong guidelines.