Two risk-scoring systems for predicting incident diabetes mellitus in U.S. adults age 45 to 64 years

Simple prediction scores could help identify adults at high risk for diabetes.

To derive and validate scoring systems by using longitudinal data from a study that repeatedly tested for incident diabetes.

Prospective cohort, divided into derivation and validation samples.

The ARIC (Atherosclerosis Risk in Communities) study, which followed participants for 14.9 years beginning in 1987 to 1989.

12 729 U.S. adults (baseline age, 45 to 64 years; 22.8% black). Follow-up was 96.1% at 5 years and 72.2% at 10 years.

Anthropometry, blood pressure, and pulse (basic system) plus a fasting blood specimen assayed for common analytes (enhanced system). Diabetes was identified in 18.9% of participants. Risk score integer points were derived from proportional hazard coefficients associated with baseline categorical variables and quintiles of continuous variables.

The basic scoring system included waist circumference (10 to 35 points); maternal diabetes (13 points); hypertension (11 points); and paternal diabetes, short stature, black race, age 55 years or older, increased weight, rapid pulse, and smoking history (< or =8 points each). The enhanced system included glucose (6 to 28 points); waist circumference (5 to 21 points); maternal diabetes (8 points); and triglycerides, black race, paternal diabetes, low high-density lipoprotein cholesterol concentration, short stature, high uric acid, age 55 years or older, hypertension, rapid pulse, and nonuse of alcohol (< or =7 points each). When applied to the validation sample, ascending quintiles of the basic system were associated with a 10-year incidence of diabetes of 5.3%, 8.7%, 15.5%, 24.5%, and 33.0%, respectively. Quintiles of the enhanced system were associated with a 10-year incidence of 3.5%, 6.4%, 11.5%, 19.3%, and 46.1%.

The risk scoring systems had no question regarding previous gestational diabetes, and knowledge of parental diabetes may be uncertain. The analyzed cohort was restricted by age and race; the systems may be less effective in other samples.

Basic information identified adults at high risk for diabetes. Additional data from fasting blood tests better identified those at extreme risk.