Optimal body mass index that can predict long-term graft outcome in Asian renal transplant recipients

Aim: There is limited data concerning the impact of recipient body mass index (BMI) on graft outcome in Asian renal transplant recipients. The aim of this study is to identify whether obesity (BMI 25 kg/m 2 ) and overweight (BMI 23 kg/m 2 ) can predict graft outcome. Methods: This is a single-centre retrospective study. All patients who received kidney transplantation between 1997 and 2005 were recruited. Patients were categorized according to two different designated BMI cut-off values. Results: One hundred and thirty-one patients were recruited with a median follow-up duration of 73 months. If a BMI cut-off value of 25 kg/m 2 was used, 86.3% patients were classified as non-obese and 13.7% as obese. Obesity was significantly associated with poor renal graft function and decreased patient and graft survival. On the other hand, 34.3% patients were classified as overweight and 65.7% patients as normal if a BMI cut-off value of 23 kg/m 2 was used. Overweight was significantly associated with a lower glomerular filtration rate only. Cox regression analysis showed that obesity (odds ratio (OR) = 3.09), acute rejection (OR = 5.68), pre-transplant diabetes mellitus (OR = 3.21) and age of recipient (OR = 1.06) were all significant independent risk factors associated with graft failure. Conclusion: Recipient BMI 25 kg/m 2 is a significant predictive factor for long-term renal graft outcome in the Asian population. With the introduction of new immunosuppressive agents, the risk of acute rejection in renal transplantation has been significantly reduced. Much of the focus nowadays has shifted to prolong graft survival. Obesity had been linked with an increased incidence of proteinuria, hypertension, hyperlipidaemia, diabetes mellitus (DM) and focal segmental glomerulosclerosis (FSGS) in the general population. 1 On the other hand, the impact of recipient obesity on patient and renal allograft survival is controversial. Higher body mass index (BMI) has been shown to be associated with increased risk for graft failure and patient death among white patients with end-stage renal disease who undergo renal transplantation. 2 The strong association between BMI and transplant outcome was supported in a retrospective analysis of 51 927 adult renal transplant recipients. Meier-Kriesche et al. showed that both abnormally low and abnormally high BMI are risk factors for decreased patient and graft survival, independent of most of the known