BEIJING -- China is estimated to have more than 45.7 million adults with asthma, but a large number of patients are undiagnosed or undertreated, according to a comprehensive study of the national prevalence, risk factors and management of asthma.

Jointly conducted by the China-Japan Friendship Hospital, Chinese Academy of Medical Sciences and other research institutions, the study was based on surveys of more than 50,000 Chinese adults aged over 20. A paper on the study was published in the medical journal Lancet in June.

Results showed that the overall prevalence of asthma among Chinese adults aged above 20 is 4.2 percent, including 4.6 percent for men and 3.7 percent for women.

The study showed that about 71.2 percent of asthma patients are undiagnosed and only around 5.6 percent have received proper treatment, indicating the urgency to raise awareness and improve the prevention and control of the chronic disease.

According to Wang Chen, president of the Chinese Academy of Medical Sciences and one of the researchers, asthma is a common disease in China and has become one of the major public health and medical care problems that need to be seriously addressed and solved.

The diagnosis rate and treatment rate of asthma remain low in China, and China needs to improve the prevention and control of asthma as soon as possible, Wang said.

Huang Kewu, a professor from Beijing Chaoyang Hospital said China needs to further standardized clinical diagnosis and treatment of asthma and increase awareness among the public and medical practitioners.