Figure 2. Moderation analysis of frailty index (FI) by (A) body mass index (BMI) and (B) education, stratified by sex. First row shows the absolute variance of FI, while the second row shows the proportion of FI variance explained by total genetic (H, indicating sum of additive and dominance genetic factors) and unique environmental (E) factors, with changes in BMI and education. Variance estimates of moderation by BMI were obtained from the full ADE bivariate moderation model between FI and BMI; while variance estimates of moderation by education were obtained from the ADE extended univariate moderation model between FI and education. Quantitative sex-differences were allowed in the models to obtain estimates separately for men and women. Models were adjusted for age. Note: Model-fitting results can be found in Supplementary Tables 5, 6.