The authors evaluated the results of the long-term monitoring of the glucose tolerance in 90 subjects, 40 men and 50 women, who were referred to a diabetological clinic as suspect diabetics. The mean age during the initial examination was 55.7 years (mean 55.7 +/- 12.5), a diabetic family--history was recorded in 60% of the patients, obesity in 61%. The monitoring proceeded on average for 8.5 years (mean 8.5 +/- 6.8). During the baseline examination diabetes was detected only in three subjects (3.3%), in 41 (45.6%) impaired glucose tolerance was revealed which in the course of 18 years developed in 28 into diabetes. In 32 examined subjects (35.6%) the oral glucose tolerance test (oGTT) was repeatedly normal, however, 9 subjects developed in the course of 23 years diabetes, although the stage of impaired glucose tolerance was not recorded. oGGT in 11 patients (12.2%) was variable in the course of the follow-up, normal glucose tolerance alternated with impaired glucose tolerance. In three subjects (3.3%) repeated examinations are consistent with renal glycosuria. From the results ensues that subjects suspect of diabetes with a marked family-history of diabetes and who are moreover obese it is important to ensure monitoring on a long-term basis as positivity during the initial examination is low (3.3%), while during long-term follow up the prevalence of diabetes is 54%. In patients with an impaired glucose tolerance there is a high risk of the development of diabetes, although the stage of impaired glucose tolerance is not always detected.

Keywords: Adult; Aged; Aged, 80 and over; Diabetes Mellitus /diagnosis/; Female; Glucose Intolerance /diagnosis/; Glucose Tolerance Test; Humans; Male; Middle Aged; Risk Factors