High Risk of Cardiovascular Mortality in Individuals With Impaired Fasting Glucose Is Explained by Conversion to Diabetes

Abstract

OBJECTIVE—To optimize identification of future diabetic patients, the American Diabetes Association (ADA) introduced criteria for impaired fasting glucose (IFG) in 1997 (IFG 6.1 mmol/l [IFG6.1]) and lowered the threshold from 6.1 to 5.6 mmol/l (IFG5.6) in 2003. Our aim was to assess the consequences of lowering the IFG cutoff on the risk of cardiovascular disease (CVD) mortality and to evaluate whether this risk is explained by a conversion to type 2 diabetes within 6.4 years. RESEARCH DESIGN AND METHODS—In a population-based cohort, the Hoorn Study, plasma glucose was determined in 1989 and 1996 (n = 1,428). Subjects were classified in 1989 according to 1997 and 2003 ADA criteria. Subjects with IFG in 1989 were further classified according to diabetes status in 1996. Hazard ratios for CVD mortality (n = 81) in the period 1996–2005 were adjusted for age and sex. RESULTS—Subjects with IFG6.1, but not IFG5.6, had a significantly higher CVD mortality risk than normal fasting glucose (NFG) subjects. Subjects who converted from IFG to diabetes (IFG6.1: 42%; IFG5.6: 21%) had a more than twofold risk of CVD mortality (IFG6.1: 2.47 [1.17–5.19]; IFG5.6: 2.14 [1.12–4.10]) than subjects with NFG. IFG subjects who did not develop diabetes did not have significantly higher CVD mortality risks (IFG6.1: 1.50 [0.72–3.15]; IFG5.6: 1.15 [0.69–1.93]). CONCLUSIONS—The lower cutoff for IFG (ADA 2003 criteria) results in a category of IFG that no longer represents a high-risk state of CVD. Furthermore, only subjects who convert from IFG to diabetes have a high risk of CVD mortality.

Dysglycaemia in non-diabetic hypertensive patients: comparison of the impact of two different classifications of impaired fasting glucose on the cardiovascular risk profile

“…See Table 3 for further statistics. 20 as FPG levels in the 100-110 mg 100 ml À1 range are weak, and statistically not significant predictors of cardiovascular risk, 18,[21][22][23] while increasing substantially the proportion of individuals labelled as prediabetic. 24 Moreover, although the 2007 ESH/ESC hypertension guidelines 7 equated MetS to target organ damage and diabetes as risk modifier, the value of a formal diagnosis of MetS in clinical practice is contentious 25 and may not overcome the contribution of its individual components for both diabetes prediction and determination of vascular risk.…”

“…30 Consistent with the notion of glucose abnormalities and hypertension as related conditions, 1 about 15% of our patients had prediabetes on the basis of more restrictive (FPGX 110 mg 100 ml À1 ) definitions of IFG, 5 a figure three-to fourfold higher than that expected in middle aged, non-diabetic, healthy Italian populations. 31 In that subgroup of patients, conversion to type 2 diabetes, particularly if coexisting with impaired glucose tolerance, 32 is a likely 10 and ominous 4,22 event, prompting lifestyle modifications 33 and, possibly, pharmacologic treatments 34 to avert that outcome. Abstinence from specific The present results are subject to some limitations.…”

Pré-diabetes: diagnóstico, avaliação de complicações crônicas e tratamento

“…Existem ainda evidências de que as duas condições, GJA ou TDG, não estão associadas a maior risco cardiovascular (18), sendo a associação com DCV somente observada naqueles pacientes que evoluí-ram para DM ao longo do seguimento (27).…”

Topics in Type 2 Diabetes and Insulin Resistance

“…Taking into account CVD risk factors may reduce the excess risk associated with pre-diabetes (15,16). Part of the difficulty in associating pre-diabetes with risk may be that only a subset of these individuals progress to diabetes, with evidence that adverse effects are restricted to those individuals who progress to development of diabetes shown in studies in the Netherlands (17) and among Pimas (18). Interestingly, A1C may be a more powerful risk factor than glucose, with analysis of the European Prospective Investigation of Cancer (EPIC)-Norfolk study showing a doubling of CVD mortality among individuals with A1C 5-5.4% or 5.5-6.9% compared with that among individuals with A1C Ͻ5% (19).…”