Association of variability in hemoglobin A1c with cardiovascular diseases and mortality in Chinese patients with type 2 diabetes mellitus - A retrospective population-based cohort study.
This study aimed to investigate the association between variability in HbA1c and incidence of cardiovascular disease (CVD) event and mortality among Chinese primary care patients with Type 2 diabetes mellitus (T2DM).



A retrospective cohort study was conducted on 91,866 T2DM patients aged ≥18years without any history of CVD. Variability in HbA1c, was measured by standard deviation (SD), associated with the risks of CVD and all-cause mortality were evaluated using Cox proportional hazards regression analysis by age groups ( 65 and ≥ 65 years old)." to "Variability in HbA1c was measured by standard deviation (SD) The association between Variability in HbA1c and the incidence of CVD and all-cause mortality were evaluated using Cox proportional hazards regression analysis by age groups ( 65 and ≥ 65 years old).



Over a median follow-up of 58.5months, our study identified a positive linear relationship between variability in HbA1c and incidence of CVD and all-cause mortality in the younger and older groups. For every 1-SD increase in HbA1c, the risk of CVD events in the older group only increased by 15.2% (95% CI: 1.026-1.293), and the risks of all-cause mortality in both age groups increased by 49.5% (95% CI: 1.154-1.936) and 77.8% (95% CI: 1.563-2.024), respectively.



The HbA1c variability independently of the mean HbA1c level may provide additional valuable information as a potential predictor for the development of CVD and all-cause mortality in diabetic patients, particularly for the elderly patients.
Department of Family Medicine and Primary Care, the University of Hong Kong, Hong Kong; School of Nursing, the University of Hong Kong, Hong Kong. Electronic address: yfwan@hku.hk.
Eric Yuk Fai
EY
Wan
Department of Family Medicine and Primary Care, the University of Hong Kong, Hong Kong. Electronic address: cfsc@hku.hk.
Colman Siu Cheung
CS
Fung
School of Nursing, the University of Hong Kong, Hong Kong. Electronic address: dytfong@hku.hk.
Daniel Yee Tak
DY
Fong
Department of Family Medicine and Primary Care, the University of Hong Kong, Hong Kong. Electronic address: clklam@hku.hk.
Cindy Lo Kuen
CL
Lam
D000368:Aged; D044466:Asian People; D002318:Cardiovascular Diseases / Q000208:ethnology*; D002681:China / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology*; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D012189:Retrospective Studies; D012307:Risk Factors
D006442:Glycated Hemoglobin
Cardiovascular diseases; Diabetes mellitus; HbA1c; Mortality; Variability