Objective: To compare the sensitivities of BMI, waist circumference and waist hip ratio (WHR) in identifying subjects who should be screened for diabetes and/or for obesity-associated dyslipidaemia.
Design: Cross-sectional study.
Setting: Central-western France.
Participants: More than 3000 men and women, aged 40-64 years, from the French study: data from an epidemiological study on the insulin resistance syndrome (D.E.S.I.R.).
Main outcome measures: Sensitivity and specificity for screened diabetes (fasting plasma glucose>or=7.0 mmol/l) and screened dyslipidaemia (triglycerides>or=2.3 mmol/l and/or HDL-cholesterol <0.9/1.1 mmol/l (men/women)) according to BMI, waist circumference and WHR.
Results: Sensitivities increased as more corpulent subjects were screened, but they increased slowly after screening the top 30%: body mass index (BMI)>or=27/26 kg/m(2) (men/women) or waist >or=96/83 cm or WHR>or=0.96/0.83. These values were chosen as thresholds. In men, BMI had a nonsignificantly higher sensitivity than waist or WHR for both diabetes and dyslipidaemia (77 vs 74 and 66% P<0.3, 0.09; 56 vs 54 and 49% P<0.5, 0.16). For women, waist had a slightly higher sensitivity than BMI or WHR (82 vs 77 and 77% P<0.8, 0.7) for diabetes; for dyslipidaemia, waist and WHR had similar sensitivities, higher than for BMI (65 and 67 vs 54% P<0.16, 0.13).
Conclusions: We propose that for screening in a French population 40-64 years of age, the more obese 30% of the population, identified either by BMI, waist or WHR be screened for diabetes and obesity-associated dyslipidaemia.