HbA1c and all-cause mortality risk among patients with type 2 diabetes

Abstract Background Several prospective studies have evaluated the association between glycosylated hemoglobin (HbA 1c ) and death risk among diabetic patients. However, the results have been inconsistent. Methods We performed a prospective study which included 13,334 men and 21,927 women with type 2 diabetes. Cox proportional hazards regression models were used to estimate the association of different levels of HbA 1c with all-cause mortality. Results During a mean follow up of 8.7years, 4199 (2082 men and 2117 women) patients died. The multivariable-adjusted hazard ratios (HRs) of all-cause mortality associated with different levels of HbA 1c at baseline ( non-linear =0.008) for men, and 1.21, 1.00, 1.01, 1.08, 1.30, 1.30 and 1.74 (P non-linear 1c with all-cause mortality was confirmed among African American and white diabetic patients, patients who were more than 50years old, never smoked or used insulin. When we used an updated mean value of HbA 1c , the J-shaped association of HbA 1c with the risk of all-cause mortality did not change. Conclusions Our study demonstrated a J-shaped association between HbA 1c and the risk of all-cause mortality among men and women with type 2 diabetes. Both high and low levels of HbA 1c were associated with an increased risk of all-cause mortality.