Mean HbA1c and HbA1c variability help predict diabetes-related complications: Study
Taiwan: Both standard deviation of HbA1c (HbA1c-SD) and mean HbA1c (HbA1c-mean) are associated with diabetes-related complications in type 2 diabetes patients, researchers state in a recent study in Diabetes Research and Clinical Practice.
"HbA1c-SD, however, was found to be more effective at predicting worsening of renal function and increased mortality, and HbA1c-mean was more effective at predicting retinopathy," the researcher wrote in their study.
Increasing studies have shown long-term glycemic control to be the main risk factor for the development of micro- and macro-vascular complications in diabetes patients. Various studies also showed that HbA1c variability was positively related to micro- and macro-vascular complications, as well as mortality.
Against the above background, Harn-Shen Chen, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, and colleagues aimed to study different effects of mean HbA1c and HbA1c variability on diabetes-related complications in patients with type 2 diabetes mellitus.
For this purpose, the researchers followed 1869 patients with type 2 diabetes in a Diabetes Shared Care Program for a median of 9.5 years. Calculation of HbA1c-mean and HbA1c-SD was done during the first 5 years. The clinical outcomes included retinopathy (any and advanced), nephropathy (urine albumin-to-creatinine ratio [UACR] > 300 mg/g and doubling of serum creatinine), and mortality (due to all-causes, and cardiovascular disease [CVD]).
Based on the study, the researchers found the following:
· HbA1c-mean was independently associated with UACR >300 mg/g (Hazard ratio [HR] 1.308), any retinopathy (HR 1.274), and advanced retinopathy (HR 1.237).
· HbA1c-SD was independently associated with UACR >300 mg/g (HR 1.478), doubling of serum creatinine (HR 2.133), all-cause mortality (HR 1.880), and CVD mortality (HR 1.431).
· Receiver operating characteristic (ROC) curves showed HbA1c-mean was more associated with any retinopathy, whereas HbA1c-SD was more associated with doubling of serum creatinine, all-cause and CVD mortality.
"Our study showed that increased mean HbA1c and HbA1c variability was linked to a significantly increased risk of developing a UACR > 300 mg/g," the researchers wrote in their study. "This indicates kidney function worsening."
"Increased mean HbA1c was tied to a significantly increased retinopathy risk, while increased HbA1c variability was linked with a significantly increased risk of doubling serum creatinine (indicating deterioration of renal function), CVD mortality, and all-cause mortality.
Reference:
Wu TE, Su YW, Chen HS. Mean HbA1c and HbA1c Variability are Associated with Differing Diabetes-related Complications in Patients with Type 2 Diabetes Mellitus. Diabetes Res Clin Pract. 2022 Sep 3:110069. doi: 10.1016/j.diabres.2022.110069. Epub ahead of print. PMID: 36067915.
