Characteristics and prognosis of Asian patients with type 2 diabetes from a multi-racial Australian community: the Fremantle Diabetes Study

Background: Asian migrants represent an expanding proportion of the Australian population and are from a region with an increasing diabetes burden. There are few data detailing the characteristics and outcome of type 2 diabetes in Asian Australians. Aims: To determine whether the phenotype and prognosis of Asians with type 2 diabetes differ from those in Anglo-Celt (AC) patients from the same Australian community. Methods: We studied 44 Asian and 796 AC patients from the Fremantle Diabetes Study. Each had a detailed assessment between 1993 and 1996, and was invited to annual reviews for >= 5 years. Data linkage provided additional endpoints to end-2010. Cox proportional hazards modelling was used to determine predictors of cardiovascular disease (CVD) death and all-cause mortality. Results: The prevalence of type 2 diabetes in Asians and the general population in Fremantle was similar (1.5% vs 1.6%; P = 0.60). The Asian patients were younger, less obese and less likely to be hypertensive than the AC subjects, but they had a higher retinopathy prevalence (27.3% vs 13.5%; P = 0.023). During up to 18 years of follow up, 12 Asians and 428 AC patients died, 2 (16.7%) vs 205 (47.9%) from CVD (P = 0.040). Asian ethnicity was independently protective against CVD death (hazard ratio 0.13 (95% confidence interval: 0.02-0.96); P = 0.046) but not all-cause mortality (hazard ratio 0.58 (95% confidence interval: 0.31-1.10); P = 0.10). Conclusions: The phenotype of type 2 diabetes in a relatively small group of well-characterised Asian Australians differed from that in AC patients from the same urban community. Their favourable cardiovascular prognosis may reflect a healthy migrant effect.