Impaired Fasting Glucose and the Risk of Incident Diabetes Mellitus and Cardiovascular Events in an Adult Population: MESA (Multi-Ethnic Study of Atherosclerosis)

Abstract

The purpose of the study was to assess the cardiovascular risk of impaired fasting glucose (IFG).The associations between IFG, incident type 2 diabetes mellitus (T2DM), and cardiovascular (CV) events remains unclear.The MESA (Multi-Ethnic Study of Atherosclerosis) study included participants who were 45 to 84 years or age and free of clinical CV disease at baseline (2000 to 2002). Type 2 DM was defined as fasting glucose >125 mg/dl or receiving antidiabetes medication at baseline and follow-up examinations; IFG was defined as no T2DM and fasting glucose 100 to 125 mg/dl. Cox proportional hazards analysis was used to assess the association between IFG and incident DM and also between IFG and incident CV events.Of 6,753 participants included in these analyses, 840 (12.7%) had T2DM and 940 (13.8%) had IFG at the baseline examination. During 7.5 years of follow-up, there were 418 adjudicated CV events. Type 2 DM was associated with an increased CV incidence in the univariate model (hazard ratio [HR]: 2.83, 95% confidence interval [CI]: 2.25 to 3.56, p < 0.0001) and multivariate model adjusted for demographics and traditional risk factors (HR: 1.87, 95% CI: 1.47 to 2.37, p < 0.0001) compared with subjects not having T2DM (IFG plus normal fasting glucose). Impaired fasting glucose was associated with increased incidence of T2DM (HR: 13.2, 95% CI: 10.8 to 16.2, p < 0.001) that remained after adjusting for demographics, highest educational level, physical activity, and body mass index (HR: 10.5, 95% CI: 8.4 to 13.1, p < 0.001) compared with normal fasting glucose. Impaired fasting glucose was associated with incident CV events in the univariate model (HR: 1.64, 95% CI: 1.26 to 2.14, p < 0.001) but not in the full multivariate model (HR: 1.16, 95% CI: 0.88 to 1.52, p = 0.3) compared with normal fasting glucose.Having IFG was not independently associated with an increased short-term risk for incident CV events. These data reiterate the importance of intervention for persons with IFG to reduce their incidence of T2DM.