Targeted screening reveals high numbers of prediabetes and diabetes mellitus in Moshi, Tanzania

Objective: Chronic non-communicable diseases, such as type 2 diabetes mellitus, have become global major health problems. In the United Republic of Tanzania, previous studies showed diabetes prevalences ranging from 0.6% to 5.8% and of pre-diabetes, from 9.1% to 10.6%. The pre-diabetes screening procedure described here was a targeted screening to recruit eligible subjects for a subsequent dietary intervention in Moshi, Tanzania. Methods: The pre-diabetes screening procedure described here was used to identify subjects for a dietary intervention in Moshi, Tanzania. Main enrollment criteria for participants were fasting plasma glucose levels of 5.6- 6.9 mmol/L (100-125 mg/dL) on two days or on one day plus HbA1c in the range of 5.7-7.5% (39-58% mmol/mol), body mass index of 27-35 kg/m2, and age between 30-65 years. Results: Through pre-screening of a total of 1,256 people were examined for BMI and age; 382 people were further screened for markers of pre-diabetes. Following ADA and WHO-criteria, 51% (73%) had normal, 35% (13%) pre-diabetic, and 15% (15%) diabetic fasting plasma glucose levels. Among the individuals with hyperglycemia indicating diabetes mellitus, 60% were unaware of their condition. Applying ADA criteria for HbA1c to all people, 42% had normal, 42% had pre-diabetic, and 16% had diabetic HbA1c levels. Identified risk factors for increased fasting plasma glucose were age, waist circumference, body mass index, and a family history of diabetes mellitus. Conclusion: Although the screening sample was not representative for the study area’s population and not diagnostic, the high rates of pre-diabetic and diabetic fasting plasma glucose levels are of public health concern. The low concordance between the data for FPG and HbA1c requires further investigation, as well as the discrepancy between ADA and WHO definitions of impaired fasting glucose