Asians more likely to have recurrent CV events than whites
The risk of death or recurrent ischaemic events are higher among Asian patients compared with their white counterparts even though Asians with acute coronary syndrome and diabetes are less likely to be obese, a recent study has found.
“Although Asian patients with acute coronary syndrome and diabetes were less likely to be obese than their white counterparts, this difference had no impact on rates of recurrent cardiovascular (CV) events in these two groups,” researchers said.
Of the 49,225 patient records obtained from five trials, 3,176 were Asians and 46,048 were whites. Asians with and without diabetes had similar body mass index (BMI) values (median 24.7 vs 24.2 kg/m2), whereas whites with diabetes had higher BMI than those without (29.3 vs 27.2 kg/m2; p<0.0001).
Compared with whites without diabetes, Asians with diabetes (hazard ratio [HR], 1.63; 95 percent CI, 1.32 to 2.02), Asians without diabetes (HR, 1.36; 1.14 to 1.64) and whites with diabetes (HR, 1.15; 1.06 to 1.25) had higher rates of the composite of death, myocardial infarction or stroke at 30 days. [Am J Med 2017;130:1170–1176]
Rates of death at 1 year were also higher among Asians with diabetes (HR, 1.84; 1.47 to 2.31), Asians without diabetes (HR, 1.38; 1.11 to 1.73) and whites with diabetes (HR, 1.47; 1.33 to 1.62) compared with whites without diabetes. No significant interactions existed between race and diabetes for ischaemic outcomes.
“In the general population, the prevalence of coronary artery disease is higher among whites than among Asians, irrespective of BMI. Our hypothesis was that worse cardiovascular outcomes would be observed in the white population, in part because of their higher BMI; however, our results did not support the hypothesis,” researchers said. [JAMA 2002;287:2519–2527; Diabetes Care 2005;28:2280–2288; Obesity (Silver Spring) 2010;18:1821–1826]
“Instead, we found that Asian patients with diabetes had more recurrent cardiovascular events compared with white patients, and that the obesity differences between the groups were not associated with greater reoccurrence of cardiovascular events,” they added.
The result suggested that diabetes caused by either the presence of insulin resistance and obesity or a defect in insulin production had a similar adverse relationship with recurrent CV events, according to researchers.
Furthermore, the high risk of recurrent CV events among Asians with diabetes, even though their BMI levels were not elevated, could be due to other population-specific risk factors, including central obesity, chronic renal insufficiency and prior cerebrovascular disease.
While Asian patients have lower BMIs compared with their white counterparts, they tend to have a higher percentage of visceral fat, according to researchers, adding that the high mortality rates among Asians with or without diabetes may be due to higher rates of bleeding with antithrombotic therapy. [Metabolism 2004;53:831–835; Maturitas 2010;65:315–319; Asia Pac J Clin Nutr 2008;17:37–42; Am Heart J 2009;157:658–665; Am J Cardiol 2007;100:391–396]
These findings imply that diabetes is associated with worse outcomes among patients with acute coronary syndrome, irrespective of their race or body weight. Also, Asians are more likely to have recurrent CV ischaemic events compared with whites.
“These observations should be considered in the context of differences in medical treatment, diet and lifestyle, obesity, diabetes complications and other factors to inform personalized treatment strategies for Asian and white patients after an acute coronary syndrome,” researchers said.
In this study, analysis was made using patient-level data extracted from five randomized clinical trials in patients with acute coronary syndrome. Researchers compared obesity levels between Asian and white populations, stratified by diabetes status. They used an adjusted Cox proportional hazards models to estimate HRs for CV outcomes after an acute coronary syndrome.