Outcomes in a diabetic population of south Asians and whites following hospitalization for acute myocardial infarction: a retrospective cohort study

Abstract

BackgroundThe aim of this study was to determine whether South Asian patients with diabetes have a worse prognosis following hospitalization for acute myocardial infarction (AMI) compared with their White counterparts. We measured the risk of developing a composite cardiovascular outcome of recurrent AMI, congestive heart failure (CHF) requiring hospitalization, or death, in these two groups.MethodsUsing hospital administrative data, we performed a retrospective cohort study of 41,615 patients with an incident AMI in British Columbia and the Calgary Health Region between April 1, 1995, and March 31, 2002. South Asian ethnicity was determined using validated surname analysis. Baseline demographic characteristics and co-morbidities were included in Cox proportional hazard models to compare time to reaching the composite outcome and its individual components.ResultsAmong the AMI cohort, 29.7% of South Asian patients and 17.6% of White patients were identified as having diabetes (n = 7416). There was no significant difference in risk of developing the composite cardiovascular outcome (Hazard Ratio = 0.90, 95% CI = 0.80-1.01). However, South Asian patients had significantly lower mortality at long term follow-up (HR = 0.62, 95% CI = 0.51-0.74) compared to their White counterparts.ConclusionsFollowing hospitalization for AMI, South Asian patients with diabetes do not have a significantly different long term risk of a composite cardiovascular outcome compared to White patients with diabetes. While previous research has suggested worse cardiovascular outcomes in the South Asian population, we found lower long-term mortality among South Asians with diabetes following AMI.

Long‐term mortality after acute myocardial infarction among individuals with and without diabetes: A systematic review and meta‐analysis of studies in the post‐reperfusion era

“…To account for the advances in acute management of AMI over recent years, we conducted a subgroup analysis of studies with the recruitment taking place before and after year 2000. For this analysis we excluded studies in which the recruitment commenced before and continued after the year 2000 with the total recruitment period exceeding 5 years . The adverse impact of diabetes on mortality was not significantly higher in studies with recruitment taking place before (HR 1.88, 95% CrI 1.75, 2.02) compared with after year 2000 (HR 1.74, 95% CrI 1.60, 1.91; P = .178).…”

“…A total of 65 articles, reporting data on 66 cohorts (10 RCTs and 56 non‐RCT) were eligible for the meta‐analysis (Figure ). Data on an estimated 202 411 deaths in 714 780 individuals, over the median (range) follow‐up of 2.0 (1‐20) years were reported …”

“…In the meta-analysis of 23/66 cohorts reporting adjusted analysis, the adverse association between diabetes and excess long-term mortality was still observed after adjusting for various confounders (adjusted HR 1.48, 95% CrI 1.43, with the total recruitment period exceeding 5 years. 35,42,50,51,54,55,57,60,64,68,69,72 The adverse impact of diabetes on mortality was not significantly higher in studies with recruitment taking place before (HR 1.88, 95% CrI 1.75, 2.02) compared with after year 2000 (HR 1.74, 95% CrI 1.60, 1.91; P = .178). Additionally, on analysing mortality according to time since index AMI, the adverse impact of diabetes was not significantly different in subgroups of studies with different follow-up lengths (up to 1, >1 to 5, >5 to 10 and >10 years; Figure 4).…”

Diabetes and Associated Complications in the South Asian Population

“…92 On the other hand, a large retrospective cohort study from Canada showed that at median follow-up of 3.5 years, South Asians actually had a lower mortality rate compared to their Canadian counterparts. 93 …”

Prevalence of Chronic Complications, Their Risk Factors, and the Cardiovascular Risk Factors among Patients with Type 2 Diabetes Attending the Diabetic Clinic at a Tertiary Care Hospital in Sri Lanka

“…Several other studies have demonstrated that South Asians with diabetes have a higher mortality rate of CAD when compared to other ethnic groups [ 10 , 13 – 15 ]. However, on the other hand, a large study done in Canada reported that South Asians had a lower mortality rate compared to their Canadian counterparts [ 16 ]. In a large multinational study on the prevalence of diabetes complications by Litwak et al, macrovascular complications were reported in 23.3% and microvascular complications in 39% among the patients in South Asia [ 17 ].…”