Verhoogde glucoseconcentraties in nuchtere toestand en na glucosebelasting: risicofactoren van het ontstaan van diabetes mellitus type 2; resultaten van de Hoorn-studie

To determine the 6-year incidence of type-2 diabetes mellitus in the general population.

Design

Prospective cohort study.

Method

For 1,342 non-diabetic subjects from the region of Hoorn, the Netherlands, aged 50-74 years at baseline in 1989/’92, a 75 g oral glucose-tolerance test was carried out and at the 6-year follow-up examination in 1996-1998. The mean follow-up duration was 6.4 years. The cumulative incidence of diabetes was calculated according to 3 different definitions of diabetes: the World Health Organization diagnostic criteria (WHO-1985 and WHO-1999), based on the fasting and the 2-hour postload glucose concentrations, and those of the American Diabetes Association (ADA-1997), based solely on the fasting glucose concentration.

Results

The cumulative incidence of diabetes was 6.1, 8.3 and 9.9 according to the WHO-1985, ADA-1997 and WHO-1999 criteria, respectively. The cumulative incidence of diabetes (WHO-1999 criteria) for subjects with both impaired glucose tolerance and impaired fasting glucose at baseline was 64.5, compared to 4.5 for subjects with normal glucose levels at baseline. The odds ratios for developing diabetes, adjusted for age, sex and follow-up duration, were 10.0 (6.1-16.5) for isolated impaired fasting glucose, 10.9 (6.0-19.9) for isolated impaired glucose tolerance, and 39.5 (17.0-92.1) for both. The waist-to-hip ratio was another important risk factor for developing diabetes.

Conclusion

In the predominantly white population the cumulative incidence of diabetes was strongly increased in case of impaired fasting or 2-hour postload glucose at baseline, particularly if both were present.