Diabetes in China may have reached "an alert level," with one in 10 adults having the disease while most patients are unaware of their condition, Chinese researchers said Tuesday.

The researchers warned in the Journal of the American Medical Association that China could face "a major epidemic of diabetes- related complications," including cardiovascular disease, stroke and chronic kidney disease in the near future without an effective national intervention.

Nearly 12 percent of Chinese adults have diabetes, while about 50 percent are at the risk of developing the disease, which means up to 113.9 million Chinese adults are diabetic and another 493.4 million are estimated to be pre-diabetic, according to the new study.

"The prevalence of diabetes in the Chinese adult population has surpassed that of India and is now close to that of the United States," said lead researcher Guang Ning, vice president of Ruijin Hospital, affiliated with the Shanghai Jiaotong University Medical School.

"Although it's not appropriate to compare them in such a simple way, China is now home to the largest diabetes population in the world," Ning told Xinhua.

Ning and colleagues with the China Noncommunicable Disease Surveillance Group investigated the prevalence of diabetes on a nationally representative sample of 98,658 Chinese adults in 2010.

A two-hour oral glucose tolerance test, currently the gold standard for the diagnosis of diabetes, was conducted among participants without a self-reported history of diagnosed diabetes.

The researchers found that the prevalence of diabetes among Chinese men was 12.1 percent and among women was 11.0 percent and that the disease is more common among urban residents than rural residents in both men and women.

Furthermore, diabetes prevalence increased with age in both men and women, and men younger than 50 years had a higher prevalence, whereas women older than 60 years had a higher prevalence, they said.

The estimated prevalence of prediabetes was 50.1 percent in Chinese adults: 52.1 percent in men and 48.1 percent in women. Rural residents had slightly higher prevalence of prediabetes than did urban residents, especially in men.

Additionally, prediabetes was more prevalent in economically underdeveloped regions, as well as in overweight and obese persons.

The researchers also found that the proportion of patients with diabetes who were aware of their condition was 30.1 percent among the Chinese general population.

Only 25.8 percent of overall patients with diabetes were treated for this condition, and only 39.7 percent of those treated had adequate glycemic control, they said.

"As the country's economy expanded quickly over the last three decades, the standards of living and lifestyles of ordinary Chinese have changed substantially," Ning said.

"With increased high-calorie, highfat, high-sugar, and high- sodium diets, decreased physical activity and more sedentary lifestyles, all factors that could lead to weight gain, diabetes and other chronic diseases are now reaching epidemic proportions in China," he said.

According to the researchers, the prevalence of diabetes was less than 1 percent in the Chinese population in 1980. In subsequent national surveys conducted in 1994 and 2000 to 2001, the prevalence of diabetes was 2.5 percent and 5.5 percent respectively.

A 2007 national survey reported that the prevalence of diabetes was 9.7 percent, representing an estimated 92.4 million adults in China with diabetes.  

"The increasing prevalence of diabetes and prediabetes poses social and public health challenges," Ning said. "We need to work hard to create a health-promoting environment, encourage self- management and strengthen public health services to ensure efficient prevention and early treatment of the disease."