Screening for diabetes in schoolchildren in Trinidad, West Indies

Although the epidemic of diabetes in adults is well established and documented, information on the epidemiology of type 2 diabetes mellitus (T2DM) in children and adolescents in Trinidad and Tobago is limited. Anecdotal reports suggest an increase in children and especially adolescents with T2DM amongst clinic attendees.

To assess the prevalence of diabetes mellitus in schoolchildren screened by mass urinary testing in Trinidad and to determine the effectiveness and cost-effectiveness of this screening method.

During January to June 2009, a cross-sectional survey was undertaken in schoolchildren aged 5-17 years, in the island of Trinidad only. Children were instructed to collect an early-morning, pre-breakfast urine sample at home and to bring it to school for testing for glycosuria. Those with an initially positive result underwent a second urine test. Those with two consecutively positive urine tests were invited to undertake an oral glucose tolerance test.

67,000 (53·6%) children from a school-age population of 125,000 were screened. Twenty-three were found to have persistent glycosuria and 21 agreed to undergo an oral glucose tolerance test. Eight fulfilled the American Diabetes Association's criteria for diabetes and five for pre-diabetes. Of the eight with confirmed diabetes (aged 7-18 years), one (male, age 12 years) was slim and ketotic and required insulin for control. Of the other seven, five were overweight (three females, two males) with a BMI >85th per centile and two females were obese (BMI >95th per centile). Five children (four females, one male) aged 12-14 years were diagnosed as pre-diabetic. There is a prevalence of 10·4/100,000 schoolchildren with T2DM, and 7·5/100,000 with impaired glucose intolerance among schoolchildren in Trinidad. Urine screening had a positive predictive value (PPV) of 65% for detecting T2DM in schoolchildren. The cost of screening 67,000 children was US$55,080, a per capita cost of US$7000, representing a 63% saving.

Despite the low PPV of urine glucose testing, our data support the view that mass screening of schoolchildren in Trinidad for T2DM is both feasible and cost-effective.