Chinese and South Asians have 40% lower mortality after diabetes than Europeans

Chinese patients have a substantially lower risk for cardiovascular complications and mortality than European patients after diabetes diagnosis, according to a new study by researchers at the Institute for Clinical Evaluative Sciences (ICES). South Asians had an equivalent risk for cardiovascular disease to Europeans but still had significantly lower mortality, suggesting that cardiovascular disease may be less fatal for Chinese and South Asians with diabetes than their European counterparts.

“We wanted to determine the risk of cardiovascular complications and of mortality following diabetes diagnosis for South Asian and Chinese patients compared to European patients and we found striking differences in mortality,” says Baiju Shah, lead author and scientist at ICES.

The population-based cohort study identified all adults with newly diagnosed diabetes in Ontario between April 2002 and March 2009. Subjects were followed until March 2011 for the first occurrence of any cardiovascular complication of diabetes and for all-cause mortality. The study found:

• Cardiovascular complications developed after diabetes at a similar rate in European (17.9 events per 1,000 person-years) and South Asian patients (16.8 events per 1,000 person-years), but at a much lower rate in Chinese patients (8.1 events per 1,000 person-years).
• The risk of cardiovascular complications in Chinese men was similar to that of European men two decades younger.
• Chinese women had a similar risk as European women a decade younger.
• Both Chinese and South Asians had more than 40 per cent lower mortality after diabetes diagnosis than European patients, even after accounting for differences in age and other illnesses.
• For South Asians, an equivalent risk for cardiovascular disease but a lower mortality suggests that cardiovascular disease may be less fatal for South Asians with diabetes than Europeans with diabetes.

“What we don’t understand is why both South Asians and Chinese people appear to be relatively protected from death once they get diabetes. Once we understand the genetic, physiologic, metabolic or behavioral mechanisms that lead to this protection, we may be able to develop new strategies to reduce the risk of diabetes complications and mortality in the overall population,” says Shah.

The study “Cardiovascular complications and mortality after diabetes diagnosis for South Asian and Chinese patients: a population-based cohort study,” was published online in May and will be in the September print issue of Diabetes Care.

Authors: Shah BR, Victor JC, Chiu M, Tu JV, Anand SS, Austin PC, Manuel DG, Hux JE.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

FOR FURTHER INFORMATION PLEASE CONTACT:

• Deborah Creatura
• Communications, ICES
• [email protected]
• (o) 416-480-4780