Figure 1.

Interaction between BMI and POPs estimating the prevalence of T2D. A, United States (37): The summary measure of six POPs was calculated by summing individual rank of six POPs (1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, p,p′-DDE, oxychlordane, trans-nonachlor, and PCB153). The summary measure was classified into five quintiles from Q1 to Q5. Among persons with the lowest quintile (Q1) of the summary POPs, BMI was not associated with the risk of T2D, and T2D itself was very rare even among obese. In addition, the risk of diabetes increased with increasing concentrations of POPs even among lean persons. The highest risk was observed in persons with high POPs and high BMI. B, Finland (40): Because only results based on individual POP, not summary measures of POPs, were presented in the paper, we selected trans-nonachlor, which showed the strongest association with T2D for this figure. Serum concentrations of trans-nonachlor were divided into <0th, 10-<50th, 50-<90th, and ≥ 90th percentiles. The positive associations of T2D with POPs became stronger as BMI increased, similar to those in the United States. However, obesity was associated with T2D even among persons with the lowest levels of trans-nonachlor. C, Spain (41): The summary measure of four PCBs was calculated by summing individual rank of four PCBs (PCB118, PCB138, PCB153, and PCB180). The summary measure was classified into four quartiles from Q1 to Q4. All odds ratios were computed with Q1 and normal weight as the reference category, with models adjusted by age, sex, total cholesterol, and triglycerides. Results were similar with those from Finland.