Differences in late cardiovascular mortality following acute myocardial infarction in three major Asian ethnic groups

Abstract

Aim:

the purpose of this study was to investigate differences in long-term mortality following acute myocardial infarction (AMI) in patients from three major ethnicities of Asia.

Methods and results:

We studied 15,151 patients hospitalized for AMI with a median follow-up of 7.3 years (maximum 12 years) in six publicly-funded hospitals in Singapore from 2000–2005. Overall and cause-specific cardiovascular (CV) mortality until 2012 were compared among three major ethnic groups that represent large parts of Asia: Chinese, Malay and Indian. Relative survival of all three ethnic groups was compared with a contemporaneous background reference population using the relative survival ratio (RSR) method. The median global registry of acute coronary events score was highest among Chinese, followed by Malay and Indians: 144 (25th percentile 119, 75th percentile 173), 138 (115, 167), and 131 (109, 160), respectively, p<0.0001; similarly, in-hospital mortality was highest among Chinese (9.8%) followed by Malay (7.6%) and Indian (6.4%) patients. In contrast, 12-year overall and cause-specific CV mortality was highest among Malay (46.2 and 32.0%) followed by Chinese (43.0 and 27.0%) and Indian (35.9 and 25.2%) patients, p<0.0001. The five-year RSR was lowest among Malay (RSR 0.69) followed by Chinese (RSR 0.73) and Indian (RSR 0.79) patients, compared with a background reference population (RSR 1.00).

Conclusions:

We observed strong inter-Asian ethnic disparities in long-term mortality after AMI. Malay patients had the most discordant relationship between baseline risk and long-term mortality. Intensified interventions targeting Malay patients as a high-risk group are necessary to reduce disparities in long-term outcomes.

Keywords

Epidemiology ethnic differences outcome

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References

Williams

. Cardiology Patient Page. Depression after heart attack: Why should I be concerned about depression after a heart attack? Circulation 2011; 123: e639–e640.

McManus

Gore

Yarzebski

. Recent trends in the incidence, treatment, and outcomes of patients with STEMI and NSTEMI. Am J Med 2011; 124: 40–47.

Feinstein

Ning

Kang

. Racial differences in risks for first cardiovascular events and noncardiovascular death: The Atherosclerosis Risk in Communities study, the Cardiovascular Health Study, and the Multi-Ethnic Study of Atherosclerosis. Circulation 2012; 126: 50–59.

Palaniappan

Wang

Fortmann

. Coronary heart disease mortality for six ethnic groups in California, 1990–2000. Ann Epidemiol 2004; 14: 499–506.

Enas

Mehta

. Malignant coronary artery disease in young Asian Indians: Thoughts on pathogenesis, prevention, and therapy. Coronary Artery Disease in Asian Indians (CADI) Study. Clin Cardiol 1995; 18: 131–135.

Iqbal

Anand

Ounpuu

. Dietary patterns and the risk of acute myocardial infarction in 52 countries: Results of the INTERHEART study. Circulation 2008; 118: 1929–1937.

Department of Statistics Singapore. http://www.singstat.gov.sg/publications/publications_and_papers/population_and_population_structure/population2013.pdf (2012, accessed 15 May 2013).

World Health Organization resources page. United Nations System. http://www.who.int/countries/sgp/en/ (accessed 12 May 2013).

Ounpuu

Yusuf

. Singapore and coronary heart disease: A population laboratory to explore ethnic variations in the epidemiologic transition. Eur Heart J 2003; 24: 127–129.

10.

Teo

. Health care for older persons in Singapore: Integrating state and community provisions with individual support. J Aging Soc Policy 2004; 16: 43–67.

11.

Tunstall-Pedoe

Kuulasmaa

Amouyel

. Myocardial infarction and coronary deaths in the World Health Organization MONICA Project. Registration procedures, event rates, and case-fatality rates in 38 populations from 21 countries in four continents. Circulation 1994; 90: 583–612.

12.

Alpert

Thygesen

Antman

. Myocardial infarction redefined–a consensus document of The Joint European Society of Cardiology/American College of Cardiology Committee for the redefinition of myocardial infarction. J Am Coll Cardiol 2000; 36: 959–969.

13.

ICD-9-CM coding and reporting official guidelines. American Hospital Association, American Medical Record Association, Health Care Financing Administration, National Center for Health Statistics. J Am Med Rec Assoc 1990; 61: S1–S17.

14.

Chan

Shah

Gao

. Recalibration of the Global Registry of Acute Coronary Events risk score in a multiethnic Asian population. Am Heart J 2011; 162: 291–299.

15.

Fox

Eagle

Gore

. The Global Registry of Acute Coronary Events, 1999 to 2009–GRACE. Heart 2010; 96: 1095–1101.

16.

Cutler

Ederer

Griswold

Greenberg

. Survival of breast-cancer patients in Connecticut, 1935–54. J Natl Cancer Inst 1959; 23: 1137–1156.

17.

Yang

Hardin

Addy

. Testing approaches for overdispersion in poisson regression versus the generalized poisson model. Biom J 2007; 49: 565–584.

18.

Suissa

. Relative excess risk: An alternative measure of comparative risk. Am J Epidemiol 1999; 150: 279–282.

19.

Khan

Grubisic

Hemmelgarn

. Outcomes after acute myocardial infarction in South Asian, Chinese, and white patients. Circulation 2010; 122: 1570–1577.

20.

Wang

Chen

Roe

. Comparison of baseline characteristics, treatment patterns, and in-hospital outcomes of Asian versus non-Asian white Americans with non-ST-segment elevation acute coronary syndromes from the CRUSADE quality improvement initiative. Am J Cardiol 2007; 100: 391–396.

21.

Cohen

Fonarow

Peterson

. Racial and ethnic differences in the treatment of acute myocardial infarction: Findings from the Get With the Guidelines-Coronary Artery Disease program. Circulation 2010; 121: 2294–2301.

22.

Das

Dorsch

Lawrance

. External validation, extension and recalibration of Braunwald’s simple risk index in a community-based cohort of patients with both STEMI and NSTEMI. Int J Cardiol 2006; 107: 327–332.

23.

Gale

Manda

Weston

. Evaluation of risk scores for risk stratification of acute coronary syndromes in the Myocardial Infarction National Audit Project (MINAP) database. Heart 2009; 95: 221–227.

24.

Lee

Brancati

Yeh

. Trends in the prevalence of type 2 diabetes in Asians versus whites: Results from the United States National Health Interview Survey, 1997–2008. Diabetes Care 2011; 34: 353–357.

25.

Ministry of Health Singapore. Costs and financing: Diabetes, www.moh.gov.sg/content/moh_web/home/costs_and_financing/HospitalBillSize/diabetes.html (accessed 14 May 2013).

26.

Raymond

Varadhan

Reynold

. Higher prevalence of retinopathy in diabetic patients of South Asian ethnicity compared with white Europeans in the community: A cross-sectional study. Diabetes Care 2009; 32: 410–415.

27.

Khan

Wang

Anand

. Ethnicity and sex affect diabetes incidence and outcomes. Diabetes Care 2011; 34: 96–101.

28.

Freeman

Payne

. Racial injustice in health care. N Engl J Med 2000; 342: 1045–1047.

29.

Choiniere

Lafontaine

Edwards

. Distribution of cardiovascular disease risk factors by socioeconomic status among Canadian adults. CMAJ 2000; 162: S13–S24.

30.

Guo

Wang

. Influence of socioeconomic status on acute myocardial infarction in the Chinese population: The INTERHEART China study. Chin Med J (Engl) 2012; 125: 4214–4220.

31.

Department of Statistics Singapore. Census of population 2010 statistical release 2, www.singstat.gov.sg/publications/publications_and_papers/cop2010/census10_stat_release2.html (2010, accessed 15 May 2013).

32.

Department of Statistics Singapore. Population trends 2013, www.singstat.gov.sg/publications/publications_and_papers/population_and_population_structure/population2013.pdf (2013, accessed 2 January 2014).