Re: Association between prediabetes and risk of all cause mortality and cardiovascular disease: updated meta-analysis
158章你的奶真好吃We thank Dr Reza-Albarrán’s interest in our study. The definition of prediabetes remains controversial among international guidelines.1-2 Although it was broadly believed that individuals with impaired glucose tolerance (IGT) defined as an elevated 2 hour plasma glucose concentration may take a higher risk of morbidity than those with impaired fasting glucose (IFG), results from observational studies were inconsistent. The Australian Diabetes, Obesity, and Lifestyle Study showed that the risk of all cause mortality was increased in those with IFG and IGT. However, IFG, but not IGT was independent predictor for cardiovascular mortality after adjustment for age, sex, and other traditional cardiovascular risk factors.3 In contrast, the DECODE (Diabetes Epidemiology: Collaborative analysis Of Diagnostic criteria in Europe) study reported that IGT, not IFG, was a strong predictor of all-cause and CVD cardiovascular, independent of fasting blood glucose.4 These inconsistencies may be caused by different study design, sample size and follow-up duration, as well as inclusion from different ethnicities. In our study, we provided a strong evidence for cardiovascular disease prevention in people with all categories of abnormal glucose metabolism, as there was no heterogeneity found for the risk of cardiovascular disease in different definitions of prediabetes in general population, as well as in patients with atherosclerotic cardiovascular disease. However, we observed that individuals with IGT were susceptible to a higher risk of all cause mortality than those with IFG, which are important for future selection of those at high risk for prevention trials.
It is interesting that data from the Whitehall II cohort study showed that only reversion from IGT-defined prediabetes to normoglycaemia was associated with a reduction in future risk of cardiovascular disease; such association was not observed in people with either HbA1c or IFG-defined prediabetes and revertion to normoglycaemia.6 However, it was also reported that in Whitehall II cohort study, prediabetes defined by HbA1c was associated with a worse prognosis than prediabetes defined by IFG or IGT. IFG or IGT was not associated with an excess risk in the adjusted analysis.7 These inconsistent results maybe caused by the analytical method and limit sample size, and should be interpreted cautiously.
158章你的奶真好吃We had no access to individual participants’ data from all the 129 included studies, therefore, we can not perform further analysis to answer the question whether prediabetes defined as IFG or elevated HbA1c remains an independent predictive factor of all cause mortality and incident cardiovascular disease if postload glucose values were adjusted. It is interesting that data from the Atherosclerosis Risk in Communities (ARIC) study showed that prediabetes definitions using HbA1c were more specific and provided modest improvements in risk discrimination for clinical complications (chronic kidney disease, cardiovascular disease, peripheral arterial disease, and all-cause mortality), and ADA fasting glucose concentration, WHO fasting glucose concentration, and 2 h postload glucose concentration were generally similar for risk discrimination of clinical outcomes.8 Therefore, we concluded prediabetes defined as IFG, IGT or elevated HbA1c was associated with an increased risk of cardiovascular disease and all cause mortality.
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4. DECODE Study Group, the European Diabetes Epidemiology Group. Glucose tolerance and cardiovascular mortality: comparison of fasting and 2-hour diagnostic criteria. Arch Intern Med 2001;161:397-405. doi:10.1001/archinte.161.3.397
5. Cai X, Zhang Y, Li M, et al. Association between prediabetes and risk of all cause mortality and cardiovascular disease: updated meta-analysis. BMJ. 2020 Jul 15;370:m2297.
6. Vistisen D, Kivimaki M, Perreault L et al. Reversion from prediabetes to normoglycaemia and risk of cardiovascular disease and mortality: the Whitehall II cohort study. Diabetologia. 2019, 62:1385-1390.
7. Vistisen D, Witte DR, Brunner EJ, et al. Risk of Cardiovascular Disease and Death in Individuals With Prediabetes Defined by Different Criteria: The Whitehall II Study.
Diabetes Care. 2018 Apr;41(4):899-906. doi: 10.2337/dc17-2530.
158章你的奶真好吃 8. Warren B, Pankow JS, Matsushita K, et al. Comparative prognostic performance of definitions of prediabetes: a prospective cohort analysis of the Atherosclerosis Risk in Communities (ARIC) study. Lancet Diabetes Endocrinol. 2017 Jan;5(1):34-42. doi: 10.1016/S2213-8587(16)30321-7.
Competing interests: 158章你的奶真好吃 No competing interests