One-hour post-load plasma glucose level during the OGTT predicts dysglycemia: Observations from the 24year follow-up of the Israel Study of Glucose Intolerance, Obesity and Hypertension

Abstract

Aims: The present study assessed the longitudinal association of an elevated 1-h plasma glucose [1-h-PG >8.6mmol/l (155mg/dl)] with and without impaired glucose tolerance [IGT; 2-h-PG 7.8-11.0mmol/l (140-199mg/dl)] with cumulative incident of diabetes and prediabetes over 24years in a non-diabetic cohort.

Methods: From 1979 to 1984, 1970 non-diabetic men and women completed an oral glucose tolerance test (OGTT), physical and biochemical measurements as well as a questionnaire related to lifestyle and medical background. During the years 2000-2004, 853 survivors of the original cohort were interviewed and re-examined for glycemic progression.

Results: Individuals with 1-h-PG >8.6mmol/l (155mg/dl) but with 2-h-PG <7.8mmol/l (140mg/dl) had a significantly elevated risk, compared to those with both 1-h-PG ⩽8.6mmol/l (155mg/dl) and 2-h-PG <7.8mmol/l (140mg/dl), for both diabetes [OR:4.35 (95%CI: 2.50-7.73)] and prediabetes outcomes [OR:1.87 (95%CI 1.09-3.26)], adjusted for sex and age, smoking, body mass index, blood pressure, fasting blood glucose and insulin.

Conclusions: The risk for diabetes associated with a 1-h level >8.6mmol/l (155mg/dl) is increased and further worsened in the presence of IGT. Identifying individuals at risk with a 1-h-PG glucose level during an OGTT is recommended.

Keywords: Diabetes; Dysglycemia; OGTT; Prediabetes; Prevention.