Prevalence of abnormal glucose tolerance in Khon Kaen Province and validity of urine stick and fasting blood sugar as screening tools.

Three hundred and fifty-five individuals, 152 males and 203 females, aged between 30 and 74 years, were randomly selected in a two stage selection process from rural communities in three districts of Khon Kaen Province, Northeast Thailand. The prevalence of impaired glucose tolerance (IGT) and non-insulin dependent diabetes mellitus (NIDDM) in the rural area of Northeast Thailand were measured. In addition, the validity of the urine stick and fasting blood sugar as screening tools against the two hours glucose loading test as golden standard were determined. The survey was conducted in July 1995. The glucose loading test was performed on 277 individuals. IGT and NIDDM were classified according to current World Health Organization suggestions. Prevalence rates for IGT were 18.1 per cent and for NIDDM 11.9 per cent. No difference was found between males and females, also when controlled for age. NIDDM prevalence increased with age but IGT rates already were high in the younger age groups. This finding suggests that IGT precedes NIDDM in Thailand. The validity of the urine stick as a screening tool in communities was insufficient, with a sensitivity of less than 20 per cent. When using fasting blood sugar as a screening test, the sensitivity was close to 44 per cent and the specificity 90 per cent. It is concluded that the urine stick is not a useful screening tool and the method of using blood sugar concentrations for screening have to be improved before it can be applied within communities.